JP4126517B2 - Vapor processing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a gas phase processing apparatus for performing gas phase etching or gas phase ashing of a polycrystalline silicon film, a photoresist film, or the like.
[0002]
[Prior art]
Conventionally, when a TFT (thin film transistor), which is a MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) using a polycrystalline silicon layer formed on a substrate as a gate electrode, is formed, a gas phase etching method for the polycrystalline silicon layer is used. Is adopted.
[0003]
As such a gas phase etching method, conventionally, a reactive gas is excited using plasma discharge, and the reaction is performed by irradiating the reaction gas to a substrate or a film on the substrate, and the reaction product is gasified and etched. In reactive etching using such plasma, normally, the collected electrons and ions generate a plasma potential (cathode drop) due to the difference in mobility, and are accelerated by the potential gradient. Since the electric field due to this potential is perpendicular to the substrate, ions and radicals are irradiated perpendicularly to the substrate, thereby obtaining etching selectivity.
[0004]
[Problems to be solved by the invention]
However, such etching has the following drawbacks because it uses plasma.
[0005]
(1) Electric field non-uniformity on the substrate due to plasma field non-uniformity, fluctuations, plasma-induced charges, etc., resulting in damage to transistors, short-circuiting (charge-up or discharge breakdown of gate oxide film, etc., between wirings May occur). This phenomenon tends to occur particularly when the plasma is turned on / off.
(2) There is a possibility of ultraviolet damage due to light emission from plasma.
(3) The metal on the inner wall of the device may be damaged by the plasma and cross contamination of metal atoms may occur.
(4) Plasma discharge over a large area is difficult, standing waves are generated, and uniformity is difficult to obtain.
(5) The apparatus is complicated and expensive, and maintenance is complicated.
[0006]
Such a problem caused by plasma also occurs when ashing the photoresist by plasma discharge.
[0007]
  Therefore, an object of the present invention is to provide an apparatus capable of highly selectively etching (and further ashing) without damaging the substrate by sufficiently controlling the kinetic energy of reactive species such as ions and radicals. It is to provide.
[0008]
[Means for Solving the Problems]
  That is, the present invention provides a reactive gasSupply means;Catalyst bodyWhen,Heating means of the catalyst body;Electric field below the glow discharge start voltageElectric field applying means to be applied andEtching or ashingIn a gas phase processing apparatus having a substrate to be processed or a susceptor supporting a substrate with a film,
    The electric field applying means has a glow discharge start voltage or lower and an AC voltage is superimposed on a DC voltage.  Or a power supply that applies an AC voltage whose absolute value is less than or equal to the glow discharge start voltage.  Ru
With featuresVapor phase processingapparatusIt is related to.
[0010]
  According to the apparatus of the present invention, a reaction gas is brought into contact with a heated catalyst body, and a reaction species generated thereby or a precursor thereof is less than a glow discharge start voltage (that is, less than a plasma generation voltage according to Paschen's law). ofBy applying a voltage obtained by superimposing an AC voltage on a DC voltage, or an AC voltage whose absolute value is equal to or lower than the glow discharge start voltageSince kinetic energy is given by applying an electric field, the following remarkable effects can be obtained.
[0011]
  (1) In addition to the catalytic action of the catalyst body and its thermal energy, a directional acceleration voltage is applied to the reactive species or its precursor, and the kinetic energy is increased and efficiently led onto the substrate. Etching or ashing proceeds due to reaction and collision with the substrate. For this reason, since the anisotropic etching is similar to the reactive ion etching, high-definition pattern etching or ashing can be performed with low damage and no ultraviolet damage. Therefore, since it covers the drawbacks of conventional reactive etching and enables highly anisotropic etching by impact of vertically incident ions, for example, selective etching of polycrystalline Si, SiO 2 on Si Selective etching, etching of Al alloy by sputtering effect, removal of Al2 O3 on Al, etching of copper and refractory metal, and removal of the resist altered layer after high dose ion implantation can be performed easily and satisfactorily.
  (2) Types and values of acceleration voltage to be applied (DC voltage (DC) with low frequency voltage superposition (AC / DC), DC voltage with high frequency voltage superposition (RF / DC), etc.), catalyst body heating temperature, touch The etching selectivity can be freely set according to the type of medium and the selection of reaction gas and conditions. High anisotropic etching, isotropic etching, control of the inclination angle of the edge portion, and the selectivity is set to 1, and the surface A variety of fine processing is possible, such as flattening.
  (3) Since no plasma is generated, there is no plasma damage, short circuit, UV damage, metal cross-contamination, etc.
  (4) Reactive species (ions, radicals, etc.) generated by the catalyst body can be independently controlled by an electric field and efficiently guided onto the substrate, so that the reaction gas is used efficiently and the processing speed is increased, thereby producing The cost can be reduced by improving the performance and reducing the reaction gas.
  (5) Compared to reactive etching using plasma, a much simpler and cheaper apparatus is realized. In this case, the operation can be performed under reduced pressure or normal pressure. However, the normal pressure type is simpler and less expensive than the reduced pressure type.
  (6) Since the kinetic energy of the reactive species is large, it is possible to process in a large area, and it is possible to process even if the substrate temperature is lowered, and a large and inexpensive insulating substrate (glass substrate, heat-resistant resin substrate) Etc.) can be used, and the cost can be reduced also in this respect.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
  In the apparatus of the present invention, as the electric field, a direct-current voltage equal to or lower than a glow discharge start voltage (that is, a plasma generation voltage or lower determined by Paschen's law, for example, 1 kV or lower, several tens of V or higher).When an AC voltage is superimposed on the AC voltage, or an AC voltage (that is, a plasma generation voltage or less determined by Paschen's law (absolute value in the case of an AC voltage), for example, 1 kV or less, several tens of V or more) is applied. Since the kinetic energy with a subtle electric field change can be given to the reactive species (ion, radical, etc.) by the alternating voltage or the alternating voltage superimposed on the substrate, the reactive species or the precursor thereof is applied to the substrate side by the direct current voltage. In addition to the above-described effects such as directing to the surface, a film provided on the surface of the substrate having a complicated shape (such as an uneven step) can be finely processed with an arbitrary selection ratio, an arbitrary inclination angle, and the like.
[0014]
In this case, the AC voltage may be a high-frequency voltage and / or a low-frequency voltage. For example, a voltage that is equal to or lower than the glow discharge start voltage and that overlaps the high-frequency voltage and the low-frequency voltage may be applied to the DC voltage. Alternatively, a voltage that is equal to or lower than the glow discharge start voltage and overlaps the high-frequency voltage and the low-frequency voltage may be applied. In this case, the frequency of the high frequency voltage is preferably 1 to 100 MHz, and the frequency of the low frequency voltage is preferably 1 MHz or less.
[0015]
  In the apparatus of the present invention, the catalyst body can be installed between the substrate or the susceptor and the electrode for applying an electric field. In this case, it is preferable that a gas supply port for leading out the reaction gas is formed in the electrode.
[0016]
The catalyst body and the electrode for applying an electric field may be installed between the substrate or the susceptor and the reactive gas supply means.
[0017]
The catalyst body or the electrode for applying an electric field may be formed in a coil shape, a mesh shape, a wire shape, or a porous plate shape, and a plurality or a plurality of electrodes may be arranged along the gas flow. This effectively forms a gas flow, increases the contact area between the catalyst body and the gas, promotes the catalytic reaction, increases the utilization efficiency of the reaction gas, improves the etching rate, improves productivity, and costs. You can go down.
[0018]
Further, during or during processing by etching or ashing, ions may be generated in the reaction gas due to the catalytic action of the catalyst body, which may cause the base to be charged up and cause unevenness in etching or ashing. In order to prevent this, it is desirable to neutralize ions by irradiating the reactive species or precursor thereof with charged particles (electron beam or proton, particularly electron beam). That is, it is preferable that charged particle irradiation means be installed in the vicinity of the susceptor.
[0019]
Then, after the gas phase processing such as etching, the substrate is taken out of the processing chamber, and a voltage is applied between predetermined electrodes (for example, between the susceptor and the counter electrode) to generate plasma discharge. Clean the room (reactive gas is CF_Four, C₂F₆Etc.), foreign matter adhering to the inner wall surface and each component in the room during the gas phase processing can be removed by etching, so that dust is reduced and the cost can be reduced by improving the yield and quality. This can be realized by using an apparatus for performing vapor phase processing as it is, so there is no need to take out the components and clean them out of the room. This improves workability and reduces costs by improving productivity. It becomes. The catalyst body can also be cleaned at the same time, but may be taken out of the room and cleaned separately.
[0020]
Specifically, the gas phase processing according to the present invention is performed by heating the catalyst body to a temperature in the range of 800 to 2000 ° C. and lower than its melting point (for example, energizing the catalyst body and heating the resistance body itself. -100 ° C to 500 ° C depending on the reaction species generated by the catalytic reaction or the thermal decomposition reaction of at least a part of the reaction gas with the heated catalyst body or the precursor thereof (radical, etc.). Vapor phase etching or gas phase ashing is performed on a substrate or a film on the substrate held at a temperature.
[0021]
Here, if the heating temperature of the catalyst body is less than 800 ° C., the catalytic reaction or thermal decomposition reaction of the reaction gas becomes insufficient, and the processing rate such as etching tends to decrease. Constituent materials are mixed in the film to inhibit the electrical characteristics of the film, resulting in deterioration of the film quality, and heating above the melting point of the catalyst body is lost in its form stability, and should be avoided. The heating temperature of the catalyst body is preferably below 1100 ° C. to 1800 ° C. below the melting point of its constituent materials.
[0022]
In addition, the substrate temperature is preferably −100 ° C. to 500 ° C., more preferably normal temperature to 200 ° C., so that efficient and high quality processing can be performed. When the substrate temperature exceeds 500 ° C., for example, in an integrated circuit device, the impurity doping concentration distribution in the active region is likely to change due to the influence of heat.
[0023]
  In the gas phase processing based on the present invention, since heat treatment at a low temperature as described above is possible without requiring plasma or photoexcitation, a glass having a low strain point of 470 to 670 ° C. is used as a substrate, for example, a glass substrate. Can be used. This is inexpensive, can be easily thinned, can be increased in size (1 m @ 2 or more), and a long rolled glass plate can be produced. For example, it can process continuously or discontinuously on a long roll glass plate using the said method.
[0024]
The reaction gas used in the gas phase processing according to the present invention is based on a dilute gas (carrier gas) such as inert Ne, Ar, He or the like, a halogen such as CFC-based or chlorine-based, or a compound gas thereof, or oxygen An oxidizing gas such as CF_Four+ He dilution O₂).
[0025]
Etching of semiconductor films such as polycrystalline silicon, single crystal silicon, amorphous silicon, silicon-germanium, silicon carbide, compound semiconductors (gallium-nitride, gallium-arsenide, gallium-phosphorus, etc.) by using the above reaction gas Etching of insulating films such as silicon oxide, silicon nitride, silicon oxynitride, and chromium oxide containing impurities such as silicon oxide, PSG (phosphorus silicate glass), BSG (boron silicate glass), and BPSG (boron phosphorus silicate glass) Refractory metals such as tungsten, tungsten nitride, titanium, titanium nitride, molybdenum, molybdenum nitride, tantalum, tantalum nitride, aluminum, aluminum alloys (including those containing 1% Si and 1-2% Cu), Metal film of silicide, copper, etc. Etching, or an organic film such as a photoresist, can be etched or ashing.
[0026]
Further, the catalyst body is formed by at least one material selected from the group consisting of tungsten, tria-containing tungsten, molybdenum, platinum, palladium, vanadium, silicon, alumina, metal-attached ceramics, and silicon carbide. Can do. The catalyst body is preferably not etched by the reaction gas. In order to prevent deterioration of the catalyst body due to etching gas or reactive gas in catalytic reaction or thermal decomposition reaction, the catalyst body is formed of a corrosion-resistant material such as platinum, platinum-coated ceramic, palladium, palladium-coated ceramic. It is good.
[0027]
  In the vapor phase processing apparatus according to the present invention, the reaction gas is changed to a raw material gas for film formation, and a predetermined film is formed on the substrate by supplying the raw material gas (that is, by catalytic CVD method). It is also preferable to perform vapor phase film formation. For example, a film is selectively removed by bias catalytic etching with the reactive gas using a mask, and a photoresist film as a mask is continuously removed by bias catalytic ashing with an oxidizing gas, and the film for continuous film formation is removed. Instead of the source gas, a predetermined film may be formed on the substrate by the bias catalyst CVD method (that is, the source gas is brought into contact with the heated catalyst body, and the reaction species generated thereby or the precursor thereof. A predetermined film may be formed on the substrate by applying kinetic energy by applying an electric field lower than the glow discharge starting voltage to the body. At this time, either AC / DC or RF / DC may be adopted as the bias.
[0028]
As a result, the apparatus for performing vapor phase processing can be used as it is, and a film can be formed by CVD only by changing the gas. Therefore, the workability is improved and the cost can be reduced by improving the productivity. That is, since thin film etching, photoresist ashing, and CVD film formation can be continuously performed, the film quality can be improved by reducing impurity contamination, and the cost can be reduced by improving productivity by improving workability.
[0029]
In the vapor phase growth by this catalytic CVD method, specifically, the catalyst body is heated to a temperature in the range of 800 to 2000 ° C. and lower than its melting point (for example, by energizing the catalyst body and heating itself by resistance). On the substrate heated to room temperature to 550 ° C. using the deposited species or the precursor thereof generated by catalytic reaction or thermal decomposition reaction of at least a part of the source gas with the heated catalyst body. A thin film is deposited by thermal CVD under reduced pressure or normal pressure.
[0030]
In this case, for the deposited species or precursor thereof, in addition to the catalytic action of the catalyst body and its thermal energy, the above voltage (particularly the glow discharge start voltage or lower, that is, the DC voltage or DC voltage lower than the plasma generation voltage according to Paschen's law). Since an acceleration voltage by applying a voltage superimposed with an alternating voltage (for example, 1 kV or less, several tens of volts or more) is given, the kinetic energy is increased and can be efficiently guided onto the substrate. Is enough. Therefore, compared to the conventional catalytic CVD method, the kinetic energy of the deposited species (reactive species such as ions and radicals) generated in the catalyst body can be controlled independently by the electric field, so the adhesion of the generated film to the substrate is improved. High-quality film that can increase the density of the generated film, improve the uniformity or smoothness of the generated film, improve the embedding property in via holes and the step coverage, further lower the substrate temperature, and control the stress of the generated film. (For example, a silicon film or a metal film having physical properties close to the bulk) is realized. Moreover, since no plasma is generated, there is no damage caused by the plasma, and a low-stress production film can be obtained.
[0031]
Here, when the heating temperature of the catalyst body is less than 800 ° C., the catalytic reaction or thermal decomposition reaction of the raw material gas becomes insufficient and the deposition rate tends to decrease. Mixing into the deposited film impairs the electrical characteristics of the film, resulting in film quality degradation, and heating above the melting point of the catalyst body loses its form stability and should be avoided. The heating temperature of the catalyst body is preferably below 1100 ° C. to 1800 ° C. below the melting point of its constituent materials.
[0032]
The substrate temperature is preferably room temperature to 550 ° C., and more preferably 150 to 400 ° C., whereby efficient and high-quality film formation can be performed. When the substrate temperature exceeds 550 ° C., inexpensive glass cannot be used, the substrate material is limited, the productivity is poor (throughput is reduced), the film thickness and the film quality are likely to be poor, and the integrated circuit is used. When forming a passivation film, the impurity doping concentration distribution is likely to change due to the influence of heat.
[0033]
In the case of forming a polysilicon film (polycrystalline silicon film) by a normal thermal CVD method, the substrate temperature needs to be about 600 to 900 ° C. However, in this film formation based on catalytic CVD, plasma or photoexcitation is required. Instead, it is extremely advantageous to be able to perform the thermal CVD at the low temperature as described above. Since the substrate temperature during the catalytic CVD is low as described above, a glass having a low strain point of 470 to 670 ° C. can be used as the substrate, for example, a glass substrate. This is inexpensive, easy to thin, and upsized (1m²The above can be made, and a long rolled glass plate can be produced. For example, a thin film can be produced continuously or discontinuously on a long rolled glass plate using the above method.
[0034]
The source gas used for the vapor phase growth is a hydrogen-based carrier gas (H₂, H₂+ Ar, H₂+ Ne, H₂+ He or the like) may be any of the following (a) to (o).
(A) Silicon hydride or its derivative
(B) A mixture of silicon hydride or a derivative thereof and a gas containing hydrogen, oxygen, nitrogen, germanium, carbon, or tin
(C) A mixture of silicon hydride or a derivative thereof and a gas containing an impurity composed of Group 3 or Group 5 elements of the periodic table
(D) A mixture of silicon hydride or a derivative thereof, a gas containing hydrogen, oxygen, nitrogen, germanium, carbon or tin, and a gas containing an impurity composed of Group 3 or Group 5 elements of the periodic table
(E) Aluminum compound gas
(F) Mixture of aluminum compound gas and gas containing hydrogen or oxygen
(G) Indium compound gas
(H) A mixture of an indium compound gas and a gas containing oxygen
(I) Refractory metal fluoride gas, chloride gas or organic compound gas
(J) Mixture of refractory metal fluoride gas, chloride gas or organic compound gas and silicon hydride or derivatives thereof
(K) A mixture of titanium chloride and a gas containing nitrogen and / or oxygen
(L) Copper compound gas
(M) A mixture of an aluminum compound gas, hydrogen or a hydrogen compound gas, and silicon hydride or a derivative thereof and / or a copper compound gas
(N) Hydrocarbon or its derivative
(O) Mixture of hydrocarbon or its derivative and hydrogen gas
[0035]
By using the above source gases, semiconductor thin films such as polycrystalline silicon, single crystal silicon, amorphous silicon, microcrystalline silicon, silicon-germanium, silicon carbide (SiC), compound semiconductors (GaAs, GaP, GaN, etc.) , Silicon oxide, silicon oxide, PSG (phosphorus silicate glass), BSG (boron silicate glass), BPSG (boron phosphorus silicate glass) and other impurity-containing silicon oxide, silicon nitride, silicon oxynitride, molybdenum oxide, titanium oxide, tantalum oxide, Insulating thin films such as aluminum oxide and indium oxide, refractory metals such as tungsten, titanium, tantalum, molybdenum, tungsten nitride, titanium nitride, tantalum nitride and molybdenum nitride, silicide, copper, aluminum, aluminum-silicon or aluminum Um - silicon - a metal thin film made of copper or the like can be grown in vapor phase.
[0036]
And it is desirable to heat-process the said catalyst body in hydrogen-type gas atmosphere before supplying the said source gas. This is because if the catalyst body is heated before the supply of the raw material gas, it is oxidized and the constituent material of the catalyst body is released, and this may be mixed into the formed film. Such contamination can be eliminated by heating at Therefore, it is preferable to heat the catalyst body in a state where a predetermined hydrogen carrier gas is supplied into the film formation chamber and then supply the source gas.
[0037]
The present invention relates to a silicon semiconductor device, a silicon semiconductor integrated circuit device, a silicon-germanium semiconductor device, a silicon-germanium semiconductor integrated circuit device, a compound semiconductor device, a compound semiconductor integrated circuit device, a silicon carbide semiconductor device, a silicon carbide semiconductor integrated circuit device, Manufactures liquid crystal display devices, electroluminescence display devices, plasma display panel (PDP) devices, light emitting polymer display devices, light emitting diode display devices, CCD area / linear sensor devices, MOS sensor devices, ferroelectric memory devices, or solar cell devices. It is suitable for doing.
[0038]
Next, the present invention will be described in more detail with respect to preferred embodiments.
[0039]
  1 to 14, an embodiment of the present inventionFirst example to serve as a reference forExplain(However, including configurations that can be adopted in the embodiments of the present invention: the same applies to other reference examples below).
[0040]
  <DC bias catalytic etching method and apparatus>
  ThisofExampleThen, CF_FourA reaction gas such as a gas is brought into contact with the heated catalyst body, and an electric field lower than the glow discharge start voltage is applied to the reaction species generated thereby or a precursor thereof to give kinetic energy, such as polycrystalline silicon on the substrate. When performing vapor-phase etching of a predetermined film, a direct-current voltage equal to or lower than a glow discharge start voltage (a direct-current voltage equal to or less than 1 kV determined by Paschen's law) is applied between the substrate and the counter electrode, and the reactive species or its precursor is Direct to the side of the board. Less than,ThisofExampleThis etching method is called a DC bias catalytic etching method.
[0041]
This DC bias catalytic etching method is performed using an apparatus as shown in FIGS.
[0042]
According to this apparatus (DC bias catalytic etching apparatus), carbon fluoride (for example, CF_FourThe reaction gas 40 such as Ar), He, Ne, N₂Together with dilution or carrier gas, the gas is introduced into the gas phase etching chamber 44 from the supply conduit 41 through the supply port 43 of the shower head 42. Inside the chamber 44 is a susceptor 45 for supporting a substrate 1 made of glass or the like having a thin film 56 such as a polycrystalline silicon layer to be etched, and has good heat resistance (preferably the same as or similar to that of the catalyst body 46. A shower head 42 (of a material having the above melting point), a coil-shaped platinum-coated ceramic, a catalyst body 46 such as tungsten, and a shutter 47 that can be opened and closed are arranged. A magnetic seal 52 is provided between the susceptor 45 and the etching chamber 44. The etching chamber 44 follows the front chamber 53 that performs the pre-process, and is evacuated through a valve 55 by a turbo molecular pump 54 or the like.
[0043]
The substrate 1 is heated by heating means such as the heater wire 51 in the susceptor 45 if necessary, and the catalyst body 46 is, for example, a resistance wire below the melting point (especially 800 to 2000 ° C., and about 1200 ° C. in the case of platinum-coated ceramics). In the case of ceramic-coated tungsten, it is heated to about 1600-1700 ° C. and activated. Both terminals of the catalyst body 46 are connected to a DC or AC catalyst body power supply 48 and heated to a predetermined temperature by energization from the power supply. Further, the shower head 42 is connected to the positive side of a variable DC power source (1 kV or less, for example, 500 V) 49 as an accelerating electrode via a conduit 41, and a DC voltage of 1 kV or less between the susceptor 45 (accordingly, the substrate 1). A bias voltage is applied.
[0044]
In order to perform this DC bias catalytic etching method, first, the gas phase etching chamber 44 is set to 10.^-3-10^-1After evacuating to Torr, the temperature of the substrate is raised to about 100 to 200 ° C., and from the state shown in FIG._FourThe reaction gas 40 is introduced from the supply port of the shower head 42 and is brought into contact with a catalyst body 46 such as a platinum-coated ceramic heated to 800 to 2000 ° C. (for example, about 1200 ° C.), and then the shutter 47 is opened.
[0045]
At least a part of the reaction gas 40 is catalytically decomposed in contact with the catalyst body 46, and a reactive species such as fluorine or a radical group (ie, reactive species or Its precursor). A reactive electric field generated by a direct current power source 49 having a glow discharge starting voltage (about 1 kV) or less, for example, 500 V, is applied to the generated reactive species 50 (or a precursor thereof) to give kinetic energy, which is directed toward the substrate 1. Etching selectivity is developed, and a predetermined film 56 such as polycrystalline silicon on the substrate 1 held at −100 ° C. to 500 ° C. (for example, room temperature to 100 ° C.) is vapor-phase etched.
[0046]
Thus, without generating plasma, the reactive species (ions, radicals, etc.) are given directional kinetic energy obtained by adding the catalytic energy of the catalytic body 46 and its thermal energy to the acceleration energy by the DC electric field, so that the reactive gas Is efficiently guided to the substrate by changing it to a reactive species, and etching proceeds by chemical reaction and collision with the substrate. For this reason, since it becomes high anisotropic etching like reactive ion etching, high-definition fine pattern etching (or ashing) can be performed with low damage and without ultraviolet damage.
[0047]
Therefore, since it covers the drawbacks of conventional reactive etching and enables anisotropic etching by impact of vertically incident ions, for example, selective etching of polycrystalline Si, SiO on Si₂Selective etching, Al alloy etching by sputtering effect, Al on Al₂O_ThreeIn addition, it is possible to easily and satisfactorily remove the resist-affected layer after etching of copper and refractory metal and after high-dose ion implantation.
[0048]
Further, the etching selectivity can be freely set according to the acceleration voltage 49 to be applied, the heating temperature of the catalyst body 46, the type of the catalyst body 46, the selection and conditions of the reaction gas 40, isotropic etching, and the inclination of the edge portion. A variety of fine processing is possible, such as controlling the angle and flattening the surface with a selection ratio of 1.
[0049]
In addition, the reaction species (ions, radicals, etc.) generated by the catalyst body 46 can be independently controlled by a direct current electric field and efficiently guided onto the substrate, so that the reaction gas utilization efficiency is high, the processing speed is increased, and the productivity is increased. Reduce costs by improving and reducing reactive gases.
[0050]
In addition, since the kinetic energy of the reactive species is large even when the substrate temperature is lowered, etching in a large area is possible, and lowering the substrate temperature reduces the cost for improving productivity by improving the throughput. The uniformity of film thickness and film quality can be improved by reducing unevenness, and a large and inexpensive insulating substrate (glass substrate, heat-resistant resin substrate, etc.) can be used. In this respect, the cost can be reduced. In addition, since the reaction gas supply showerhead 42 can also be used as an electrode for accelerating the reactive species, the structure is simplified. Since the shower head 42 can blow out gas uniformly, etching unevenness or ashing unevenness hardly occurs.
[0051]
Needless to say, no plasma is generated during etching, so there is no plasma damage, short circuit, UV damage, metal cross-contamination, etc., much more than plasma etching (reactive etching). A simple and inexpensive device is realized.
[0052]
In this case, under reduced pressure (for example 10^-3Although the operation can be performed under a few torr) or normal pressure, the normal pressure type is simpler and cheaper than the reduced pressure type. Even in the normal pressure type, the above electric field is applied, so that highly selective etching can be performed. Also in this case, the normal pressure type has a higher throughput than the reduced pressure type, so that the productivity is high and the cost can be reduced.
[0053]
In the case of the decompression type, the DC voltage depends on the degree of vacuum (reaction gas flow rate), the type of reaction gas, and the like, but in any case, it is necessary to adjust the DC voltage to an arbitrary voltage equal to or lower than the glow discharge start voltage. In the case of the normal pressure type, it is desirable to adjust the exhaust so that the exhaust gas flow does not contact the substrate so that the flow of the reaction gas and the reaction species does not adversely affect the film quality of the film on the substrate.
[0054]
In the etching described above, the substrate temperature rises due to the secondary heat generated by the catalyst body 46. As described above, the temperature adjusting device, for example, the substrate heating heater 51 (or the supply of the coolant for cooling the substrate) is used as necessary. Means) may be installed. Further, the catalyst body 46 is in a coil shape (in addition to this, a mesh, a wire shape, or a porous plate shape may also be used). Increasing the number is desirable in terms of improving the reaction gas utilization efficiency by promoting the catalytic reaction and improving the processing speed. In this etching, since the substrate 1 is arranged above the shower head 42 on the lower surface of the susceptor 45, particles generated in the chamber 44 do not fall and adhere to the substrate 1 or a film thereon. Therefore, it is possible to improve the yield and quality by reducing dust. Of course, conversely, the substrate 1 may be placed on the upper surface of the susceptor 45 and disposed below the shower head 42 (in this case, productivity can be improved).
[0055]
  Furthermore,ThisofExampleIn FIG. 4, after performing the above-mentioned DC bias catalytic etching, the substrate 1 is taken out of the etching chamber 44 as shown in FIG._Four, C₂F₆Etc., and the reaction gas 57 is introduced (the degree of vacuum is 10^-2The high frequency voltage 58 (or DC voltage) is applied between the susceptor 45 of the substrate 1 and the shower head 42 as the counter electrode to generate plasma discharge, thereby cleaning the inside of the chamber 44. it can. In this case, the plasma generation voltage is 1 kV or more, for example, 2 to 3 kW, and the voltage is 1.5 to 2.0 kV.
[0056]
That is, foreign substances adhering to the inner wall surface in the chamber 44, the susceptor 45, the shower head 42, the shutter 47, and the catalyst body 46 during the gas phase etching can be removed by etching, so that dust is reduced. The cost can be reduced by improving the yield and quality. This can be realized by using an apparatus for performing vapor phase processing as it is, so there is no need to take out and clean the constituent members outside the chamber 44, which improves workability and reduces costs by improving productivity. Is possible. The catalyst body 46 can also be cleaned at the same time (however, the catalyst body power supply 48 is turned off), but may be taken out of the chamber 44 and separately cleaned.
[0057]
The thin film 56 to be etched is supplied with a film forming raw material gas instead of the reaction gas 40 in the apparatus shown in FIGS. 1 to 3, and a predetermined thin film 56 is formed from a gas phase by catalytic CVD. Can be membrane. That is, from the state shown in FIG. 5, as shown in FIG. 6, a source gas 140 such as silane gas is introduced from the supply port of the shower head 42 and heated to 800 to 2000 ° C. (for example, about 1650 ° C.). The shutter 47 is opened after contacting the catalyst body 46.
[0058]
At least a part of the source gas 140 is catalytically decomposed in contact with the catalyst body 46, and a group of ions such as silicon and radicals having high energy (that is, deposited species or precursor thereof) by catalytic decomposition reaction or thermal decomposition reaction. Body). A kinetic energy is applied to the deposition species 150 (or precursors thereof) such as ions and radicals generated in this manner by applying a direct current electric field by a direct current power source 49 of a glow discharge starting voltage (about 1 kV) or less, for example, 500 V, to the substrate 1 side. Then, a predetermined film 56 such as polycrystalline silicon is vapor-phase grown on the substrate 1 maintained at room temperature to 550 ° C. (for example, 200 ° C.).
[0059]
Thus, directivity kinetic energy obtained by adding the acceleration energy of the direct current electric field to the catalytic action of the catalytic body 46 and its thermal energy is given to the reactive species (ions, radicals, etc.) without generating plasma during film formation. Therefore, the source gas can be efficiently converted into reactive species, and can be uniformly deposited on the substrate 1 by thermal CVD using a DC electric field. Since the deposited species 56 migrate on the substrate 1 and diffuse in the thin film, it is possible to form a flat and uniform thin film 56 with high density and good step coverage.
[0060]
Therefore, such DC bias catalytic CVD is a thin film with an arbitrary DC electric field independent of the control factors of conventional catalytic CVD, such as the substrate temperature, the catalyst body temperature, the degree of vacuum (source gas flow rate), the source gas type, and the like. The feature is to add control over generation. For this reason, the adhesion of the produced film to the substrate, the produced film density, the produced film uniformity or smoothness, the embedding property in the via hole and the step coverage are improved, the substrate temperature is further lowered, and the produced film is Stress control and the like, and a high quality film (for example, a silicon film or a metal film having physical properties close to a bulk) can be obtained. In addition, the reactive species (ions, radicals, etc.) generated by the catalyst body 46 can be independently controlled by a direct current electric field and deposited on the substrate efficiently, so that the utilization efficiency of the source gas is high and the production rate is increased. The cost can be reduced by improving the performance and reducing the raw material gas.
[0061]
Similarly to the above-described DC bias catalytic etching, the kinetic energy of the deposited species is large even when the substrate temperature is lowered, so that a desired high-quality film can be obtained, the substrate temperature can be lowered, and the plasma can be lowered. As a result, there is no damage caused by plasma, and a high quality film with good density, uniformity and adhesion can be obtained with low stress.
[0062]
Summarizing the above processes, as schematically shown in FIG. 7, after a photoresist PR is formed in a predetermined pattern on a film IL such as an insulating film on the substrate S, the film IL is subjected to bias catalytic etching with a reactive gas. The photoresist film PR is continuously removed by bias catalyst ashing with a reactive gas after removing a part, and further changed to a raw material gas for film formation, and a predetermined film UL is formed on the substrate S by bias catalyst CVD. Can be formed. As a result, thin film etching, photoresist ashing, and CVD film formation can be performed continuously with the same configuration of equipment, so the film quality can be improved by reducing impurity contamination, and the productivity can be reduced by improving workability. Is possible.
[0063]
In this case, in bias catalytic etching, He, Ne, Ar, N, or the like is used as a dilution gas or carrier gas.₂Alternatively, a mixture of inert gases mixed with the reaction gas may be used. In bias catalyst ashing, He, Ne, Ar, N as dilution gas or carrier gas₂Alternatively, an inert gas obtained by adding an oxidizing gas to the mixed inert gas may be used. Then, it is necessary to completely remove the photoresist film. In bias catalytic CVD, H₂, H₂+ Ar, H₂+ Ne, H₂+ He, H₂H, such as + Ar + Ne + He₂A gas based hydrogen carrier gas added with each source gas may be used.
[0064]
The thin film 56 can be formed by a conventional catalytic CVD apparatus disclosed in Japanese Patent Laid-Open No. 63-40314. According to this catalytic CVD apparatus, as shown in FIG. 8, for example, a silicon hydride (for example, monosilane) gas 140 (and, if necessary, B₂H₆And PH_ThreeEtc.) is introduced into the chamber 141 from the supply conduit. Inside the deposition chamber 141, a susceptor 142 for supporting the substrate 1 and a coil-shaped catalyst body 46 disposed to face the susceptor are arranged. Then, the substrate 1 is heated by an external heating means 144 (for example, an electric heating means), and the catalyst body 46 is heated, for example, as a resistance wire to below the melting point (particularly 800 to 2000 ° C., in the case of tungsten, about 1700 ° C.) and activated. Is done.
[0065]
In the deposition chamber 141, the atmosphere is ventilated from nitrogen to hydrogen gas (about 15 to 20 minutes), and then the temperature is raised to about 200 to 800 ° C., and the silane gas comes into contact with the catalyst body 46 and decomposes catalytically. And deposited on the substrate 1 held at a low temperature (for example, 300 ° C.). The deposition time is determined from the thickness of the polycrystalline silicon layer to be grown. After the growth is completed, the temperature is lowered, the hydrogen-based gas is ventilated with nitrogen, and the substrate 1 is taken out. In this way, high energy silicon atoms or groups of atoms are formed by the catalytic reaction or thermal decomposition reaction by the catalyst body 46 and deposited on the insulating substrate 1, so that the deposition possible temperature in the normal thermal CVD method is achieved. The polycrystalline silicon layer can be deposited in a much lower temperature region.
[0066]
  <Manufacture of MOSTFT>
  next,ThisofExampleAn example of manufacturing a MOSTFT using a DC bias catalytic etching method according to FIG.
[0067]
First, as shown in FIG. 9 (1), an insulating substrate 1 such as quartz glass or crystallized glass (strain point 800 to 1400 ° C., thickness) is used. On one main surface of 0.1 mm to several mm), the catalytic CVD method (substrate temperature 200 to 800 ° C.) disclosed in JP-A-63-40314 or the like, or the above-described DC bias catalytic CVD method (substrate temperature) Is room temperature to 550 ° C., for example, 200 to 300 ° C., and the degree of vacuum is 10^-1-10^-3Torr, eg 10^-2The polycrystalline silicon film 7 is grown to a thickness of several μm to 0.005 μm (for example, 0.1 μm) by using Torr and a bias voltage of 1 kV or less (for example, 500 V).
[0068]
In this case, after the atmosphere in the film formation chamber is ventilated from nitrogen to a hydrogen-based gas (about 15 to 20 minutes), the temperature of the substrate 1 is raised to about 200 to 300 ° C., and the degree of vacuum in the film formation chamber is set to 10 degrees.^-1-10^-3Torr (eg 10^-2Torr), for example, hydrogen carrier gas 150 SCCM (Standard cc per minute: hereinafter the same), monosilane 15-20 SCCM (and B as required)₂H₆And PH_ThreeIncluding a doping gas such as ).
[0069]
The substrate 1 is heated to room temperature to 550 ° C. (for example, 200 to 300 ° C.), and the catalyst body 46 is heated to a melting point or less (particularly 800 to 2000 ° C., for example, about 1650 ° C. for a tungsten wire) as a resistance wire. Turn into. The hydrogen carrier gas and the raw material gas are brought into contact with a heated catalyst body 46 such as tungsten.
[0070]
At least a part of the hydrogen-based carrier gas and the source gas is catalytically decomposed in contact with the catalyst body 46, and a group of high-energy silicon ions, radicals, and hydrogen ions (that is, a catalytic decomposition reaction or a thermal decomposition reaction (that is, Deposition species or precursors thereof). Thereafter, the shutter 47 is opened, and the generated species 150 (or precursors thereof) such as ions and radicals are deposited on the substrate 1. Alternatively, a kinetic energy is applied by applying a DC electric field from a DC power source 49 of a glow discharge starting voltage (about 1 kV) or less, for example, 500 V, and directed toward the substrate 1 to be room temperature to 550 ° C. (for example, 200 to 300 ° C.). A polycrystalline silicon film 7 is grown on the substrate 1 held in a vapor phase.
[0071]
Thus, the polycrystalline silicon film 7 having a thickness of, for example, about 0.1 μm is deposited. This deposition time is determined from the thickness of the layer to be grown, and after the growth is completed, the temperature is lowered, the hydrogen-based gas is ventilated with nitrogen, and the substrate 1 is taken out.
[0072]
Then, a MOS transistor (TFT) having the polycrystalline silicon layer 7 as a channel region is manufactured.
[0073]
That is, as shown in (2) of FIG. 9, for example, a thermal oxidation process (950 ° C.) or a DC bias catalytic CVD method similar to the above with oxygen gas diluted with helium (He) gas and monosilane gas supplied. A gate oxide film 8 having a thickness of, eg, 350 mm is formed on the surface of the crystalline silicon layer 7. When the gate oxide film 8 is formed by the DC bias catalytic CVD method, the substrate temperature and the catalyst body temperature are the same as those described above, but the hydrogen carrier gas 150 SCCM, the monosilane gas 15-20 SCCM, He diluted O₂The gas may be 1 to 2 SCCM.
[0074]
Next, as shown in FIG. 9 (3), in order to control the impurity concentration of the channel region for the N-channel MOS transistor, the P-channel MOS transistor portion is masked with a photoresist 9, and P-type impurity ions (for example, B⁺) 10 is 2.7 × 10 at 30 kV, for example.¹¹atoms / cm²A polycrystalline silicon layer 11 in which the conductivity type of the polycrystalline silicon film 7 is changed to the P type is implanted.
[0075]
Next, as shown in FIG. 9 (4), in order to control the impurity concentration of the channel region for the P-channel MOS transistor, this time, the N-channel MOS transistor portion is masked with the photoresist 12, and N-type impurity ions (for example, P⁺) 13 for example at 50 kV and 1 × 10¹¹atoms / cm²Then, a polycrystalline silicon layer 14 is formed in which the P type of the polycrystalline silicon film 7 is compensated.
[0076]
Next, as shown in FIG. 10 (5), the phosphorus-doped polycrystalline silicon film 15 as the gate electrode material is replaced with, for example, a hydrogen-based carrier gas 150 SCCM, PH_ThreeThe film is deposited to a thickness of, for example, 4000 mm by the same DC bias catalytic CVD method (substrate temperature 200 to 300 ° C.) as described above under the supply of 5 to 10 SCCM and monosilane gas 15 SCCM (substrate temperature 200 to 300 ° C.).
[0077]
Next, as shown in FIG. 10 (6), a photoresist 16 is formed in a predetermined pattern, and this is used as a mask, and the above-described DC bias catalytic etching method (dilution gas (carrier gas) shown in FIGS. 150SCCM, CF_Four+ He dilution O₂The polycrystalline silicon film 15 is patterned into a gate electrode shape by 5-10 SCCM, the catalyst body temperature is platinum coated ceramics at 1200 ° C. and the substrate temperature is from room temperature to 100 ° C.
[0078]
Further, dilution gas (carrier gas) 150 SCCM, oxidizing gas (for example, He dilution O₂) The photoresist 16 is removed by DC bias catalytic ashing with 5-10 SCCM. Thereafter, as shown in (7) of FIG.₂An oxide film 17 is formed on the surface of the gate polycrystalline silicon film 15 by an oxidation process in the inside.
[0079]
Next, as shown in FIG. 10 (8), the P-channel MOS transistor portion is masked with a photoresist 18, and N-type impurities such as As⁺The ion 19 is 5 × 10 at 70 kV, for example.¹⁵atoms / cm²At a dose of 950 ° C. for 40 minutes, N₂N channel MOS transistor N by annealing in⁺A type source region 20 and a drain region 21 are formed.
[0080]
Next, as shown in FIG. 11 (9), the N-channel MOS transistor portion is masked with a photoresist 22, and P-type impurities such as B⁺For example, the ion 23 is 5 × 10 at 30 kV.¹⁵atoms / cm²Ion implantation at 900 ° C. for 5 minutes, N₂By annealing in the P channel MOS transistor P⁺A type source region 24 and a drain region 25 are formed.
[0081]
Next, as shown in FIG. 11 (10), the hydrogen-based carrier gas 150SCCM is commonly used on the entire surface by a normal CVD method or a catalytic CVD method similar to that described above.₂15-20 SCCM SiH_FourSiO under supply₂For example, the film 26 is formed to a thickness of 500 mm at 200 to 300 ° C., and NH of 50 to 60 SCCM._Three15-20 SCCM SiH_FourUnder supply, the SiN film 27 is laminated to a thickness of 2000 mm at, for example, 200 to 300 ° C., and further, He diluted B of 10 to 20 SCCM.₂H₆, 10-20 SCCM He diluted PH_Three10-20 SCCM He diluted O₂15-20 SCCM SiH_FourUnder supply, a boron and phosphorus-doped silicate glass (BPSG) film 28 is formed as a reflow film to a thickness of 6000 mm at 200 to 300 ° C., for example.₂Reflow in.
[0082]
Next, as shown in (11) of FIG. 11, a DC bias catalytic etching method (provided that the reactive gas is CF based on a diluting gas or a carrier gas) at a predetermined position of the insulating film under the same conditions as described above._Four+ He diluted O₂In the same way, the photoresist is removed by DC bias catalytic ashing, and then an electrode material such as aluminum is deposited on the entire surface including each contact hole to a thickness of 1 μm at 150 ° C. by sputtering or the like. The DC bias catalytic etching method under the same conditions as above (however, the reaction gas is CCl based on the dilution gas or the carrier gas)._Four+ He diluted O₂In the same manner, the photoresist is removed by DC bias catalytic ashing, and then the source or drain electrode 29 (S or D) of each of the P channel MOSTFT and N channel MOSTFT and the gate extraction electrode or wiring 30 ( G) to form each top gate type MOS transistor.
[0083]
If the above-mentioned aluminum is formed by DC bias catalytic CVD, for example, DC bias catalytic etching, DC bias catalytic ashing, DC bias catalytic CVD, and the like can be performed using the same apparatus.
[0084]
  <Manufacture of LCD>
  next,ThisofExampleA manufacturing example of a liquid crystal driving substrate (hereinafter referred to as a TFT substrate) of a liquid crystal display device (LCD) using the DC bias catalytic etching method according to FIG.
[0085]
8 or 5 to 6, first, as shown in (1) of FIG. 12, in the pixel portion and the peripheral circuit portion, an insulating substrate 1 (such as quartz glass or crystallized glass) ( The DC bias catalytic CVD method described above (substrate temperature is room temperature to 550 ° C., for example, 200 to 300 ° C., vacuum degree is 10) on one main surface of strain point 800 to 1400 ° C. and thickness 0.1 mm to several mm.^-1-10^-3Torr, eg 10^-2In the case of applying Torr or bias voltage, the polycrystalline silicon film 67 is grown to a thickness of several μm to 0.005 μm (for example, 0.1 μm) by 1 kV or less, for example, 500 V).
[0086]
In this case, after the atmosphere in the film formation chamber is ventilated from nitrogen to a hydrogen-based gas (about 15 to 20 minutes), the degree of vacuum in the film formation chamber is set to 10%.^-1-10^-3For example, hydrogen carrier gas 150 SCCM, monosilane gas 15-20 SCCM (and B as required)₂H₆And PH_ThreeIncluding a doping gas such as ) Is introduced in the same manner as described above.
[0087]
The substrate 1 is heated to room temperature to 550 ° C. (for example, 200 to 300 ° C.) in the same manner as described above, and the catalyst body 46 is, for example, a resistance wire below the melting point (particularly 800 to 2000 ° C., for example, tungsten wire is 1700 to 1800 ° C. ) Is activated by heating. Then, the source gas is brought into contact with a heated catalyst body 46 such as tungsten.
[0088]
At least a part of the raw material gas is catalytically decomposed in contact with the catalyst body 46, and a group of high-energy silicon ions, radicals, and hydrogen ions (that is, a deposition species or a precursor thereof) by a catalytic decomposition reaction or a thermal decomposition reaction. Body) and deposited on the substrate 1. Alternatively, a kinetic energy is applied to the generated species 150 (or its precursor) such as ions and radicals by applying a direct current electric field from a direct current power source 49 of a glow discharge starting voltage (about 1 kV) or less, for example, 500 V, to A polycrystalline silicon film 67 is vapor-phase grown on the substrate 1 held at room temperature to 550 ° C. (for example, 400 ° C.).
[0089]
Thus, a polycrystalline silicon film 67 having a thickness of, for example, about 0.1 μm is deposited. This deposition time is obtained from the thickness of the layer to be grown, and after the growth is finished, the temperature is lowered, hydrogen is ventilated to nitrogen, and the substrate 1 is taken out.
[0090]
Next, as shown in (2) of FIG. 12, the polycrystalline silicon film 67 is patterned using a photoresist mask to form transistor active layers in each part.
[0091]
Next, as shown in FIG. 12 (3), the polycrystalline silicon film 67 is subjected to, for example, a thermal oxidation process (950 ° C.) or a DC bias catalytic CVD method similar to the above under the supply of He-diluted oxygen gas and monosilane gas. A gate oxide film 68 having a thickness of 350 mm, for example, is formed on the surface. When the gate oxide film 68 is formed by the DC bias catalytic CVD method, the substrate temperature and the catalyst body temperature are the same as those described above, but the hydrogen-based carrier gas 150 SCCM, monosilane gas 15-20 SCCM, He diluted O₂The gas may be 1 to 2 SCCM.
[0092]
Next, B is used to control the impurity concentration in the channel region of the transistor active layer 67.⁺Or P⁺After ion implantation of a predetermined impurity such as, as shown in FIG. 12 (4), as a gate electrode material, for example, aluminum is deposited to a thickness of, for example, 4000 mm by sputtering, or a polycrystalline silicon film is formed. The film is deposited to a thickness of, for example, 4000 mm by a DC bias catalytic CVD method (substrate temperature: 200 to 300 ° C.) similar to the above while supplying a monosilane gas of 15 to 20 SCCM based on a hydrogen carrier gas. Thereafter, a high concentration, low resistance polycrystalline silicon film is formed by phosphorus diffusion or the like. Then, using the photoresist mask 160, the gate electrode material layer is patterned into the shape of the gate electrode 75 by the DC bias catalytic etching method under the same conditions as described above. In addition, after removing the photoresist mask by the DC bias catalytic ashing method, for example, at 900 ° C. for 60 minutes, O₂An oxide film may be formed on the surface of the gate polycrystalline silicon film 75 by an oxidation treatment therein.
[0093]
Next, as shown in FIG. 13 (5), the P-channel MOS transistor portion is masked with a photoresist 78, and N-type impurities such as As⁺(Or P⁺) The ion 79 is 1 × 10 at 70 kV, for example.¹⁵atoms / cm²The ion implantation is performed at a dose of 10%, and the photoresist film is removed by a DC bias catalytic ashing method.₂N channel MOS transistor N by annealing in⁺A type source region 80 and a drain region 81 are formed.
[0094]
Next, as shown in FIG. 13 (6), the N-channel MOS transistor portion is masked with a photoresist 82, and P-type impurities such as B⁺For example, the ion 83 is 1 × 10 at 30 kV.¹⁵atoms / cm²The ion implantation is carried out at a dose of 10%, and the photoresist film is removed by a DC bias catalytic ashing method.₂By annealing in the P channel MOS transistor P⁺A type source region 84 and a drain region 85 are formed.
[0095]
The photoresists 78 and 82 shown in FIGS. 13 (5) and 13 (6) are dissolved and removed. In order to achieve this, the ashing reaction gas is used in the DC bias catalytic etching apparatus described above. (Eg O₂Or CF_Four, C₂F₆And a DC bias electric field of 1 kV or less (for example, 500 V) is applied at a substrate temperature of about 200 ° C. and a catalyst body temperature of about 1600 ° C. The insoluble matter on the photoresist surface is removed by ashing by reactive species such as radicals generated thereby. Thereafter, the photoresist is treated with a solvent and completely dissolved and removed. Such ashing may be performed in the same manner in the manufacture of the MOSTFTs shown in FIGS. Depending on the type of reaction gas, the DC bias condition, and the state of the photoresist, the photoresist can be completely removed only by ashing, so that subsequent solvent treatment is unnecessary.
[0096]
Next, as shown in FIG. 13 (7), the hydrogen carrier gas 150SCCM is made common by the same DC bias catalytic CVD method as described above on the entire surface, and He-diluted O of 1-2SCCM.₂15-20 SCCM SiH_FourSiO under supply₂For example, the film is formed to a thickness of 500 mm at 200 to 300 ° C._Three15-20 SCCM SiH_FourUnder the supply, a SiN film is laminated to a thickness of 2000 mm at, for example, 200 to 300 ° C., and further, He diluted B of 10 to 20 SCCM.₂H₆, 10-20 SCCM He diluted PH_Three10-20 SCCM He diluted O₂15-20 SCCM SiH_FourUnder supply, a boron and phosphorus-doped silicate glass (BPSG) film is formed as a reflow film to a thickness of 6000 mm at, for example, 200 to 300 ° C.₂Reflow in. An interlayer insulating film 86 is formed by stacking these insulating films. In addition, you may form such an interlayer insulation film by the normal method different from the above.
[0097]
Next, as shown in FIG. 14 (8), a contact window is opened by a DC bias catalytic etching method at a predetermined position of the insulating film 86 under the same conditions as described above, and similarly by a DC bias catalytic ashing method. After removing the photoresist, an electrode material such as aluminum is deposited on the entire surface including each contact hole to a thickness of 1 μm at 150 ° C. by sputtering or the like, and this is patterned by the same DC bias catalytic etching method as described above. Similarly, the photoresist is removed by DC bias catalytic ashing, and then the source electrode 87 of the N channel MOSTFT in the pixel portion, the source electrodes 88 and 90 of the P channel MOSTFT and N channel MOSTFT in the peripheral circuit portion, and the drain electrode 89. , 91 are formed.
[0098]
If the aluminum is formed by DC bias catalytic CVD, for example, DC bias catalytic etching, DC bias catalytic ashing, DC bias catalytic CVD, and the like can be performed in the same order in the same apparatus.
[0099]
Then the SiO on the surface₂After forming the interlayer insulating film 92 such as by the bias catalytic CVD method or the catalytic CVD method, as shown in FIG. 14 (9), contact holes are opened in the interlayer insulating films 92 and 86 in the pixel portion, for example, ITO (Indium) tin oxide: a transparent electrode material in which tin is doped into indium oxide) is deposited on the entire surface by vacuum evaporation or the like, and patterned to form a transparent pixel electrode 93 connected to the drain region 81 (at this time, the catalyst Etching and ashing may be used to open contact holes and remove the photoresist film, respectively). Thus, a TFT substrate for a transmissive LCD can be manufactured. It should be noted that the above-described steps can be similarly applied to the manufacturing of a reflective LCD TFT substrate.
[0100]
  FIG. 15 shows an embodiment of the present invention.Second example to serve as a reference forWill be explained.
[0101]
  ThisofExampleThen, the first mentioned aboveReference exampleIn the DC bias catalytic etching method and apparatus therefor, as shown in FIG. 15, it is characteristic that a charged particle or ion (for example, electron) shower 100 is provided in the vicinity of the substrate 1 or the susceptor 45. Therefore, the first mentioned aboveReference exampleIn addition to the effects of the following, the following excellent effects can be obtained.
[0102]
That is, reactive species such as ions or precursors thereof are generated in the reaction gas by the catalytic action of the catalyst body 46 during the etching of the above-described polycrystalline silicon film or the like, and thereby the substrate 1 is charged up and etched. Although unevenness may occur, the charge on the substrate 1 can be neutralized by, for example, irradiating electrons from the electron shower 100 to the ions and the like, and the charge-up can be sufficiently prevented. In particular, if the substrate 1 is made of an insulator, it is easy to accumulate electric charges, and therefore the use of the electron shower 100 is effective.
[0103]
  FIG. 16 shows an embodiment of the present invention.Third example to serve as a reference forWill be explained.
[0104]
  ThisofExampleThen, the first mentioned aboveReference exampleIn the DC bias catalytic etching method and apparatus therefor, as shown in FIG. 16, the electrode for accelerating the reactive species is a mesh electrode 101 disposed between the substrate 1 and the catalyst body 46. is there.
[0105]
That is, a plurality of mesh electrodes 101a and 101b having gas passage holes 101c are arranged between the substrate 1 and the catalyst body 46, and a DC voltage 49 of 1 kV or less is applied between them, as described above. In addition, kinetic energy in the direction of the substrate 1 is imparted to the reactive species generated by the decomposition of the reactive gas by the catalyst body 46. Therefore, in addition to the same effect as the first embodiment described above, the acceleration electrode designed and processed in advance can be easily inserted into the gap between the substrate 1 and the catalyst body 46 as the mesh electrode 101. The acceleration electrode can be disposed after being previously processed into a shape that increases acceleration efficiency. Both the mesh electrode 101 and the shower head 42 are preferably made of heat resistance (desirably, a material having a melting point equal to or higher than that of the catalyst body 46).
[0106]
  FIG. 17 shows an embodiment of the present invention.Fourth example to serve as a referenceWill be explained.
[0107]
  ThisofExampleThen, the third mentioned aboveReference exampleIn contrast, one acceleration mesh electrode 101a is disposed between the catalyst body 46 and the shower head 42, and the other acceleration mesh electrode 101b is disposed between the substrate 1 and the catalyst body 46. Is different.
[0108]
  Therefore,thisIn the example, since the mesh electrodes 101 a and 101 b exist on both sides of the catalyst body 46, it is considered that the generated reactive species can be more easily directed toward the substrate 1. The mesh electrodes 101 a and 101 b are desirably formed of a high heat resistant material having a melting point equal to or higher than that of the catalyst body 46 together with the shower head 42.
[0109]
  FIG. 18 shows an embodiment of the present invention.5th example to serve as a reference forWill be explained.
[0110]
  ThisofExampleThen, the shape of the acceleration electrode 101 described above is the perforated plate shape of FIG. 18A and the mesh shape of FIG. 18B, and the acceleration action is efficiently exhibited without obstructing the gas flow. Such a shape can be similarly applied to the catalyst body 46.
[0111]
  FIG. 19 shows an embodiment of the present invention.6th example to serve as a reference forWill be explained.
[0112]
  ThisofExampleThen, the first mentioned aboveReference exampleWhen operating the DC bias catalytic etching apparatus under normal pressure, for example, a vent hole 102 is formed in the susceptor 45 so that the gas flow does not contact the film on the substrate 1, and the exhaust gas 103 is moved upward from the peripheral region of the substrate 1. To the exhaust port (not shown).
[0113]
Therefore, even if operated at normal pressure, the film on the substrate 1 or the substrate is not contaminated. Moreover, since it is a normal pressure type, the apparatus configuration is simplified and the throughput is improved.
[0114]
  20-23, the embodiment of the present inventionSeventh example to serve as a reference forWill be explained.
[0115]
  Each of the aboveReference exampleThen, although the board | substrate 1 was distribute | arranged above the shower head 42,ThisofExampleHowever, as shown in FIG. 20, the only difference is that the substrate 1 is arranged below the shower head 42, and the other configuration and operation method are the same. Therefore, basically, the first mentioned aboveReference exampleThe same effect can be obtained.
[0116]
As a specific configuration example, there is a normal pressure type. First, as shown in FIG. 21, a plurality of substrates 1 are arranged on a rotating susceptor 45 with a heater via a rotating table 104, and the center of the susceptor is arranged. A reaction gas 40 is supplied from a rotary shower head 42 having a conduit / rotating shaft 105 in the hole, and a reaction species by a catalyst body 46 (power supply is not shown: the same applies hereinafter) is converted into a DC electric field by a DC power supply 49. Then, the film is guided onto the substrate 1 and the film thereon is etched. The exhaust gas is guided downward from the periphery of the susceptor 45.
[0117]
In this example, etching is performed by accelerating the reactive species in the direction of the substrate while rotating the plurality of substrates 1 and the shower head 42, so that the mass distribution is good and the gas distribution becomes uniform and the etching uniformity is improved. To do.
[0118]
Further, in the example shown in FIG. 22, the susceptor 45 with the rotation-type heater 106 revolves around the conical buffer 107, the substrate 1 is fixed on each susceptor 45, and the conical bell jar 108 is The reactive gas 40 is supplied from the shower head 42, the reactive species by the catalyst body 46 is accelerated by the DC voltage 49 applied between the susceptor 45 (substrate 1) and the mesh electrode 101, and the film on the substrate 1 is etched. .
[0119]
In this example, the reaction species are accelerated in the direction of the substrate while rotating and revolving a plurality of substrates 1 in a conical bell jar, so that the mass distribution is good and the gas distribution is uniform and the etching uniformity. Is further improved.
[0120]
FIG. 23 shows an example of another continuous atmospheric pressure etching apparatus, in which the substrate 1 is arranged on the transport belt 109, the reaction gas 40 is supplied from the shower head 42, and the reaction species by the catalyst body 46 is transferred to the transport belt 109 ( The film is accelerated by the DC voltage 49 applied between the substrate 1) and the mesh electrode 101, and the film on the substrate 1 is etched. Since the exhaust gas 103 is guided upward of the substrate 1, there is no problem such as contamination of the film.
[0121]
In the case of this example, the reactive species are accelerated in the direction of the substrate while the substrate 1 is transported in one direction, and the exhaust gas is discharged upward. Therefore, the mass productivity of etching is good, and even the normal pressure type is etched. easy.
[0122]
  FIG. 24 shows an embodiment of the present invention.Eighth example for referenceWill be explained.
[0123]
  ThisofExampleFor example, the film forming apparatus can selectively etch, for example, five chambers and sequentially etch the film. The substrate 1 is vacuum-sucked by the susceptor 45, loaded into the load unit 111 by the robot 110 of the load station, and sequentially sent to each chamber by the tission head 112, while the substrate surface faces downward as shown in FIG. Etching is performed in this state. However, the catalyst body 46 and the acceleration electrode described above are not shown.
[0124]
In the case of this example, it is advantageous for etching of the laminated film, the convection effect is small because the heat source of the substrate 1 is above, and the adhesion of particles can be suppressed because the substrate 1 faces down.
[0125]
  First embodiment
  25 to 26, the first of the present invention.1The embodiment will be described.
[0126]
<RF / DC bias catalytic etching method and apparatus>
In this embodiment, CF_FourA reactive gas such as a gas is brought into contact with a heated catalyst body, and an electric field lower than the glow discharge starting voltage is applied to the reaction species generated thereby or its precursor to give kinetic energy, and polycrystalline silicon on an insulating substrate, etc. When a predetermined film is etched in a gas phase, a voltage (a voltage of 1 kV or less determined by Paschen's law) is applied between the substrate and the counter electrode, which is equal to or lower than the glow discharge start voltage and a high-frequency voltage superimposed on a DC voltage. Then, the reactive species or the precursor thereof is directed to the substrate side, and kinetic energy is given by a subtle electric field change. Hereinafter, the etching method according to the present embodiment is referred to as an RF / DC bias catalyst etching method.
[0127]
This RF / DC bias catalytic etching method is carried out using an apparatus as shown in FIGS.
[0128]
According to this apparatus (RF / DC bias catalytic etching apparatus), as described with reference to FIGS._FourThe reaction gas 40 is introduced into the gas phase etching chamber 44 from the supply conduit 41 through the supply port of the showerhead 42 together with a dilution or carrier gas such as Ar as necessary. Inside the chamber 44 is a susceptor 45 for supporting the substrate 1 made of glass or the like having a thin film 56 such as polycrystalline silicon to be etched, and has good heat resistance (preferably the same as or higher than the catalyst body 46). A shower head 42 (of a material having a melting point of), a catalyst body 46 such as a coiled platinum-coated ceramic, tungsten, and a shutter 47 that can be opened and closed. A magnetic seal is provided between the susceptor 45 and the etching chamber 44. Moreover, the chamber 44 is followed by the front chamber which performs a pre-process, and is exhausted through a valve by a turbo molecular pump or the like.
[0129]
The substrate 1 is heated if necessary by a heating means such as a heater wire in the susceptor 45, and the catalyst body 46 is, for example, a resistance wire below the melting point (particularly 800 to 2000 ° C., in the case of platinum-coated ceramics, about 1200 ° C., In the case of platinum-coated tungsten, it is heated to about 1600 to 1700 ° C.) and activated. Both terminals of the catalyst body 46 are connected to a DC or AC catalyst body power supply 48 and heated to a predetermined temperature by energization from the power supply. The shower head 42 is connected to the positive side of a variable DC power source (1 kV or less, for example, 500 V) 49 from the conduit 41 through a low-pass (high frequency) filter 113 as an accelerating electrode. 115 (100-200V_PP1-100 MHz, for example 150V_PPAnd a DC bias voltage superimposed with a high frequency voltage of 1 kV or less is applied to the susceptor 45 (accordingly, the substrate 1).
[0130]
In order to perform this RF / DC bias catalytic etching method, first, the inside of the gas phase etching chamber 44 is 10^-3-10^-2After exhausting to Torr, the temperature is raised to about 100 to 200 ° C., and from the state shown in FIG. 25, as shown in FIG._FourA reactive gas 40 such as a gas is introduced from the supply port of the shower head 42 and is brought into contact with a catalyst body 46 such as a platinum-coated ceramic heated to 800 to 2000 ° C. (for example, about 1200 ° C.), and then the shutter 47 is opened. .
[0131]
At least a part of the reaction gas 40 comes into contact with the catalyst body 46 and is catalytically decomposed. By the catalytic decomposition reaction or the thermal decomposition reaction, a reactive species such as fluorine or a group of radicals (ie, reactive species) given high energy. Or a precursor thereof). The reaction species 50 (or its precursor) thus generated has a glow discharge starting voltage (about 1 kV) or less, for example, a DC voltage of a DC power supply 49 of 500 V is 100 to 200 V._PPAn RF / DC bias electric field on which a high-frequency voltage of a 13.56 MHz high-frequency power supply 115 is superimposed is applied to give kinetic energy due to a subtle electric field change, directing the substrate 1 side, and sufficient etching selectivity. Then, a predetermined film 56 such as polycrystalline silicon on the substrate 1 held at −100 ° C. to 500 ° C. (for example, normal temperature to 100 ° C.) is etched.
[0132]
  Thus, without generating plasma, directivity of reactive species (ions, radicals, etc.) by adding the catalytic energy of the catalyst body 46 and its thermal energy to acceleration energy accompanied by electric field change due to (DC + RF) electric field. Since kinetic energy is applied, the reactive gas is efficiently converted into a reactive species and efficiently guided onto the substrate, and etching proceeds due to a chemical reaction, collision with the substrate, etc. by a (direct current + high frequency) electric field. For this reason, since it is as highly anisotropic etching as reactive ion etching, pattern etching or ashing can be performed with low damage and without UV damage, and subtle by high-frequency voltage superimposed on DC voltage. Since kinetic energy due to a change in electric field can be given to reactive species (ions, radicals, etc.), the firstReference exampleIn addition to the functions and effects described above, a film provided on the surface of a substrate having a complicated shape (such as an uneven step) can be finely processed with an arbitrary selection ratio, an arbitrary inclination angle, and the like.
[0133]
Therefore, it covers the shortcomings of conventional reactive etching and enables high anisotropic etching by impact of ions incident vertically under a (DC + high frequency) electric field. For example, selective etching of polycrystalline Si, SiO on Si₂Selective etching, Al alloy etching by sputtering effect, Al on Al₂O_ThreeIn addition, it is possible to easily and satisfactorily remove the resist-affected layer after etching of copper and refractory metal and after high-dose ion implantation.
[0134]
Further, the etching selectivity can be freely set according to the acceleration voltage 49 to be applied, the heating temperature of the catalyst body 46, the type of the catalyst body 46, the selection and conditions of the reaction gas 40, isotropic etching, and the inclination of the edge portion. A variety of fine processing is possible, such as controlling the angle and flattening the surface with a selection ratio of 1.
[0135]
In addition, the reaction species (ions, radicals, etc.) generated by the catalyst body 46 can be independently controlled by a (DC + RF) electric field and efficiently guided onto the substrate, so that the reaction gas utilization efficiency is high and the processing speed is increased. Earlier, cost can be reduced by improving productivity and reducing reactive gases.
[0136]
In addition, since the kinetic energy of the reactive species is large even when the substrate temperature is lowered, etching in a large area is possible, and lowering the substrate temperature reduces the cost for improving productivity by improving the throughput. The uniformity of film thickness and film quality can be improved by reducing unevenness, and a large and inexpensive insulating substrate (such as a glass substrate or a heat-resistant resin substrate) can be used. In this respect, the cost can be reduced. In addition, since the reaction gas supply showerhead 42 can also be used as an electrode for accelerating the reactive species, the structure is simplified. Since the shower head 42 can blow out gas uniformly, etching unevenness or ashing unevenness hardly occurs.
[0137]
Of course, since no plasma is generated, there is no plasma damage, short circuit, UV damage, metal cross-contamination, etc., which is much simpler than plasma etching (reactive etching). An inexpensive device is realized.
[0138]
In this case, under reduced pressure (for example 10^-3Although the operation can be performed under a few torr) or normal pressure, the normal pressure type is simpler and cheaper than the reduced pressure type. Even in the normal pressure type, the above electric field is applied, so that highly selective etching can be performed. Also in this case, the normal pressure type has a higher throughput than the reduced pressure type, so that the productivity is high and the cost can be reduced.
[0139]
In the case of the decompression type, the (DC + high frequency) voltage depends on the degree of vacuum (reaction gas flow rate), the type of reaction gas, etc., but in any case, it is necessary to adjust it to an arbitrary voltage below the glow discharge start voltage. is there. In the case of the normal pressure type, it is desirable to adjust the exhaust so that the exhaust gas flow does not contact the substrate so that the flow of the reaction gas and the reaction species does not adversely affect the film quality of the film on the substrate.
[0140]
In the etching described above, the substrate temperature rises due to the secondary heat generated by the catalyst body 46. As described above, the temperature adjusting device, for example, the substrate heating heater 51 (or the supply of the coolant for cooling the substrate) is used as necessary. Means) may be installed. Further, the catalyst body 46 is coiled (other than this, mesh, wire, or porous plate may be used). Further, the catalyst body 46 has a plurality of stages (for example, 2 to 3 stages) in the gas flow direction to increase the contact area with the gas. Is good. In this etching, since the substrate 1 is arranged above the shower head 42 on the lower surface of the susceptor 45, particles generated in the chamber 44 do not fall and adhere to the substrate 1 or a film thereon. . Of course, conversely, the substrate 1 may be placed on the upper surface of the susceptor 45 and disposed below the shower head 42 (in this case, productivity can be improved).
[0141]
Further, in the present embodiment, after performing the above RF / DC bias catalytic etching, the substrate 1 is taken out of the chamber 44 as shown in FIG._Four, C₂F₆Etc., and the reaction gas 57 is introduced (the degree of vacuum is 10^-2The high frequency voltage 58 (or DC voltage) is applied between the susceptor 45 of the substrate 1 and the shower head 42 as the counter electrode to generate plasma discharge, thereby cleaning the inside of the chamber 44. it can. In this case, the plasma generation voltage is 1 kV or more, for example, 2 to 3 kW and 1.5 to 2.0 kV.
[0142]
  In the present embodiment also, the above-mentioned firstReference exampleAs described above, the RF / DC bias catalytic etching method can be applied to the manufacture of MOS TFTs and the TFT substrates of liquid crystal display devices (LCDs) instead of the DC bias catalytic etching method.
[0143]
  Also figure25In FIG. 2, the RF / DC bias catalytic etching method described above can be performed by providing a switch 116 as shown by a one-dot chain line in front of the matching circuit 114 and turning it on. Further, when the switch 116 is turned off, only the first DC power source 49 is operated.Reference exampleThe DC bias catalytic etching method can be performed.
[0144]
  Second embodiment
  With reference to FIG.2The embodiment will be described.
[0145]
  In the present embodiment, the above-described first1In the RF / DC bias catalytic etching method and apparatus of the embodiment, as shown in FIG. 27, a charged particle or ion (for example, electron) shower 100 is disposed in the vicinity of the substrate 1 or the susceptor 45. It is characteristic. Therefore, the above-mentioned number1In addition to the operational effects of the embodiment, the following excellent operational effects can be obtained.
[0146]
That is, ions are generated in the reaction gas by the catalytic action of the catalyst body 46 during or during the etching of the above-described polycrystalline silicon film, etc., which may cause the substrate 1 to be charged up and cause etching unevenness. For example, it is possible to neutralize the charge on the substrate 1 by electrons irradiated from the electron shower 100 and sufficiently prevent the charge-up. In particular, if the substrate 1 is made of an insulator, it is easy to accumulate electric charges, and therefore the use of the electron shower 100 is effective.
[0147]
  Note that the above1In the embodiment of the thirdReference example~ 6thReference exampleIn the same manner as described above, if the mesh electrode 101 for acceleration and the susceptor 45 with the vent hole 102 are provided, the same effect can be obtained.
[0148]
Third embodiment
  With respect to FIG.3The embodiment will be described.
[0149]
In each of the embodiments described above, the substrate 1 is disposed above the shower head 42. However, in the present embodiment, only the substrate 1 is disposed below the shower head 42, and other configurations, The operation method is the same. Accordingly, basically, the same operational effects as those of the ninth embodiment described above can be obtained.
[0150]
As a specific configuration example, there is a normal pressure type, which may be applied to an etching apparatus having a configuration as shown in FIGS.
[0151]
  Fourth embodiment
  With reference to FIG.4The embodiment will be described.
[0152]
<AC / DC bias catalytic etching method and apparatus>
In this embodiment, CF_FourA reactive gas such as a gas is brought into contact with a heated catalyst body, and an electric field lower than the glow discharge starting voltage is applied to the reaction species generated thereby or its precursor to give kinetic energy, and polycrystalline silicon on an insulating substrate, etc. When the predetermined film is subjected to gas phase etching, a voltage (a voltage of 1 kV or less determined by Paschen's law) between the substrate and the counter electrode is a glow discharge starting voltage or lower and a low-frequency voltage superimposed on a DC voltage. Applying and directing the reactive species or precursor thereof to the substrate side, and giving kinetic energy in the electric field change. Hereinafter, the etching method according to the present embodiment is referred to as an AC / DC bias catalytic etching method.
[0153]
This AC / DC bias catalytic etching method is carried out by using an etching apparatus having the same configuration except that the low frequency power source 125 is used instead of the high frequency power source 115 as shown in FIG. 29 in the ninth embodiment. The
[0154]
That is, the shower head 42 is connected to the positive electrode side of a variable DC power supply (1 kV or less, for example, 500 V) 49 as an accelerating electrode via the conduit 41 (the above-mentioned low-pass filter 113 may be omitted depending on the frequency) and matched. The low frequency power supply 125 (100 to 200 V) is supplied via the circuit 114._PPAnd 1 MHz or less, for example 150 V_PP, 26 kHz), and a DC bias voltage with a low frequency voltage of 1 kV or less is applied to the susceptor 45 (accordingly, the substrate 1).
[0155]
  In this way, directivity obtained by adding the acceleration energy accompanied by the electric field change due to the (DC + low frequency) electric field to the catalytic action of the catalyst body 46 and its thermal energy to the reactive species (ions, radicals, etc.) without generating plasma. Thus, the reactive gas is efficiently changed to reactive species, and the film on the substrate 1 can be uniformly etched by a (direct current + low frequency) electric field. In addition, the above-mentioned1The same effect as the embodiment can be obtained.
[0156]
In the present embodiment, after performing the AC / DC bias catalytic etching described above, the substrate 1 is taken out of the chamber 44 as shown in FIG._Four, C₂F₆Etc., and the reaction gas 57 is introduced (the degree of vacuum is 10^-2The high frequency voltage 58 (or DC voltage) is applied between the susceptor 45 of the substrate 1 and the shower head 42 as the counter electrode to generate plasma discharge, thereby cleaning the inside of the chamber 44. it can. In this case, the plasma generation voltage is 1 kV or more, for example, 2 to 3 kW and 1.5 to 2.0 kV.
[0157]
  In the present embodiment also, the above-mentioned firstReference exampleAs described above, the AC / DC bias catalytic etching method can be applied to the manufacture of MOSTFTs and liquid crystal display devices (LCDs) instead of the DC bias catalytic etching method.
[0158]
  Fifth embodiment
  With reference to FIG.5The embodiment will be described.
[0159]
  In the present embodiment, in each of the above-described embodiments, the reactive gas used is changed in various ways to etch or ash various corresponding thin films. Here, any of the above-described catalytic etching or ashing methods of RF / DC bias and AC / DC bias can be applied. At this time, the reaction gas dilution gas or carrier gas may be He, Ne, Ar, N₂Alternatively, an inert gas such as a combination of these is used.
[0160]
FIG. 31 shows the source gas species used in the above-described CVD film formation and various corresponding thin films.
[0161]
The embodiment of the present invention described above can be variously modified based on the technical idea of the present invention.
[0162]
For example, the above-described etching or ashing conditions and apparatus configuration, the reaction gas used, and the type of material to be processed may be variously changed.
[0163]
Further, instead of the above-described electron shower for preventing charge-up, other negatively charged particles can be irradiated, or positively charged particles such as protons may be irradiated depending on the polarity of charge-up.
[0164]
  In addition, the above1And the second4Also in the above embodiment, the above-mentioned third to eighthReference exampleThe electric field applying means described in the above can be employed. The electric field applying means may form only a high frequency or low frequency AC electric field (however, the absolute value of the high frequency or low frequency AC voltage is equal to or lower than the glow discharge start voltage). If the absolute value is equal to or lower than the glow discharge start voltage, a voltage obtained by superimposing a high frequency voltage and a low frequency voltage on DC may be applied, or a voltage obtained by superimposing a low frequency voltage and a high frequency voltage may be applied. Good. The object of etching or ashing according to the present invention may be a substrate itself such as glass or a semiconductor other than a film on the substrate.
[0165]
[Effects of the invention]
  According to the present invention, a reaction gas is brought into contact with a heated catalyst body, and a reaction species generated thereby or a precursor thereof is less than a glow discharge start voltage.By applying a voltage obtained by superimposing an AC voltage on a DC voltage, or an AC voltage whose absolute value is equal to or lower than the glow discharge start voltageSince an electric field is applied to give kinetic energy and a substrate or a predetermined film on the substrate is subjected to gas phase etching or ashing, the following remarkable effects can be obtained.
[0166]
(1) In addition to the catalytic action of the catalyst body and its thermal energy, the accelerating voltage by the above voltage is applied to the reactive species or precursor thereof, so that the kinetic energy increases and can be efficiently guided onto the substrate. Etching or ashing proceeds due to collision with the surface. For this reason, since it becomes high anisotropic etching like reactive ion etching, pattern etching or ashing can be performed with low damage and without ultraviolet damage. Therefore, since it covers the drawbacks of conventional reactive etching and enables highly anisotropic etching by impact of vertically incident ions, high-precision microfabrication, for example, selective etching of polycrystalline Si , SiO on Si₂Selective etching, Al alloy etching by sputtering effect, Al on Al₂O_ThreeIn addition, it is possible to easily and satisfactorily remove the resist-affected layer after etching of copper and refractory metal and after high-dose ion implantation.
[0167]
  (2) The etching selectivity can be freely set according to the type and value of the acceleration voltage (AC / DC, RF / DC, etc.) to be applied, the heating temperature of the catalyst body, the type of catalyst body, the selection of the reaction gas, and the conditions, Fine processing with a wide variety of changes is possible, such as high selectivity or isotropic etching, control of the inclination angle of the edge portion, and flattening of the surface with a selectivity of 1.
[0168]
(3) Since no plasma is generated, there is no plasma damage, short circuit, UV damage, metal cross-contamination, etc.
[0169]
  (4) The reaction species (ions, radicals, etc.) generated by the catalyst body can be independently controlled by any electric field such as RF / DC, AC / DC, etc., and can be efficiently guided to the substrate, so that the reaction gas utilization efficiency The process speed can be increased to improve productivity and reduce reaction gas.
[0170]
(5) Compared to reactive etching using plasma, a much simpler and cheaper apparatus is realized. In this case, the operation can be performed under reduced pressure or normal pressure. However, the normal pressure type is simpler and less expensive than the reduced pressure type.
[0171]
(6) Since the kinetic energy of the reactive species is large, it is possible to process in a large area, and it is possible to process even if the substrate temperature is lowered, and a large and inexpensive insulating substrate (glass substrate, heat-resistant resin substrate) Etc.), and in this respect, the cost can be reduced. Further, by further reducing the temperature of the substrate, it is possible to reduce the cost by improving the productivity by improving the throughput and to improve the uniformity of the film thickness and the film quality by reducing the substrate temperature unevenness.
[Brief description of the drawings]
FIG. 1 shows the first of the present invention.Reference example1 is a schematic cross-sectional view of a DC bias catalytic etching apparatus according to FIG.
FIG. 2 is a schematic cross-sectional view of the catalyst etching apparatus during etching.
FIG. 3 is a more detailed schematic sectional view of the catalyst etching apparatus.
FIG. 4 is a schematic sectional view of the catalyst etching apparatus during cleaning.
FIG. 5 is a schematic sectional view of the DC bias catalytic CVD apparatus.
FIG. 6 is a schematic sectional view of the DC bias catalytic CVD apparatus during CVD.
FIG. 7 is a schematic cross-sectional view showing a process when bias catalyst etching, bias catalyst ashing, and bias catalyst CVD are sequentially performed.
FIG. 8 is a schematic sectional view of the catalytic CVD apparatus.
FIG. 9 is a cross-sectional view showing a manufacturing process of a MOSTFT using a catalytic etching apparatus in the order of steps.
FIG. 10 is a cross-sectional view showing the manufacturing process of the MOSTFT using the catalytic etching apparatus in the order of steps.
11 is a cross-sectional view showing the manufacturing process of the MOSTFT using the catalytic etching apparatus in the order of steps. FIG.
FIG. 12 is a cross-sectional view showing the manufacturing process of the LCD using the catalyst etching apparatus in the order of steps.
13 is a cross-sectional view showing the manufacturing process of the LCD using the catalyst etching apparatus in the order of steps. FIG.
FIG. 14 is a cross-sectional view showing the manufacturing process of the LCD using the catalyst etching apparatus in the order of steps.
FIG. 15 shows the second of the present invention.Reference exampleIt is a schematic sectional drawing of the principal part of the DC bias catalyst etching apparatus by.
FIG. 16 shows the third of the present invention.Reference exampleIt is a schematic sectional drawing of the principal part of the DC bias catalyst etching apparatus by.
FIG. 17 shows the fourth of the present invention.Reference exampleIt is a schematic sectional drawing of the principal part of the DC bias catalyst etching apparatus by.
FIG. 18 shows the fifth of the present inventionReference example1 is a schematic perspective view of an acceleration electrode used in a DC bias catalytic etching apparatus according to FIG.
FIG. 19 shows the sixth of the present invention.Reference exampleIt is a schematic sectional drawing of the principal part of the DC bias catalyst etching apparatus by.
FIG. 20 shows the seventh aspect of the present invention.Reference exampleIt is a schematic sectional drawing of the principal part of the DC bias catalyst etching apparatus by.
FIG. 21 is a schematic cross-sectional view of the main part of another DC bias catalyst etching apparatus.
FIG. 22 is a schematic sectional view of another DC bias catalytic etching apparatus.
FIG. 23 is a schematic sectional view of another DC bias catalytic etching apparatus.
FIG. 24 shows the eighth embodiment of the present invention.Reference exampleIt is a schematic plan view of the principal part of the DC bias catalyst etching apparatus by.
FIG. 25 shows the first of the present invention.1It is a schematic sectional drawing of the RF / DC bias catalyst etching apparatus by embodiment of this.
FIG. 26 is a schematic cross-sectional view of the catalyst etching apparatus during etching.
FIG. 27 shows the first of the present invention.2It is a schematic sectional drawing of the principal part of the RF / DC bias catalyst etching apparatus by embodiment of this.
FIG. 28 shows the first of the present invention.3It is a schematic sectional drawing of the principal part of the RF / DC bias catalyst etching apparatus by embodiment of this.
FIG. 29 shows the first of the present invention.4It is a schematic sectional drawing of the AC / DC bias catalyst etching apparatus by embodiment of this.
FIG. 30 shows the first of the present invention.5It is a figure which shows the combination of the various reaction gas and to-be-processed film in RF / DC or AC / DC bias catalyst etching or ashing by embodiment of this.
FIG. 31 is a diagram showing a combination of a source gas and a thin film used for forming a thin film by CVD.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Substrate, such as glass, 40 ... Reaction gas, 41 ... Conduit,
42 ... Shower head, 44 ... Gas phase etching chamber, 45 ... Susceptor,
46 ... Catalyst body, 47 ... Shutter, 48 ... Catalyst body power supply, 49 ... DC power supply,
56 ... thin film, 58, 115 ... high frequency power supply, 100 ... electron shower,
101, 101a, 101b ... mesh electrode, 113 ... low pass filter,
114 ... matching circuit, 125 ... low frequency power supply

Claims (14)

A reaction gas supply means; a catalyst body; a heating means for the catalyst body; an electric field application means for applying an electric field equal to or lower than a glow discharge start voltage; and a susceptor for supporting a substrate to be etched or ashed or a substrate with a film. in the vapor phase processing apparatus having,
Electric field applying means, that has a power supply voltage is an AC voltage superimposed on a DC voltage equal to or lower than the glow discharge starting voltage, or the absolute value is applied to the following AC voltage glow discharge starting voltage
A gas phase processing apparatus characterized by that . The vapor phase processing apparatus according to claim 1 , wherein a voltage that is equal to or lower than a glow discharge start voltage and in which a high-frequency voltage and a low-frequency voltage are superimposed on a DC voltage is applied. The vapor phase processing apparatus according to claim 1 , wherein a voltage that is equal to or lower than a glow discharge start voltage and is a superposition of a high frequency voltage and a low frequency voltage is applied. The vapor phase processing apparatus according to claim 2 or 3 , wherein the frequency of the high-frequency voltage is 1 to 100 MHz and the frequency of the low-frequency voltage is 1 MHz or less. Wherein the catalyst is placed between the susceptor and the electrode for the electric field application, vapor processing apparatus according to claim 1. Wherein the catalyst and the electrode for the electric field application is installed, vapor processing apparatus according to claim 1 between said reactive gas supplying means and the susceptor. The vapor phase processing apparatus according to claim 1 , wherein the catalyst body or the electrode for applying an electric field is formed in a coil shape, a mesh shape, a wire shape, or a porous plate shape. The vapor phase processing apparatus according to claim 1 , wherein charged particle irradiation means is installed in the vicinity of the susceptor. The gas phase processing apparatus according to claim 1 , further comprising plasma discharge forming means for applying a voltage between predetermined electrodes to clean the inside of the gas phase processing chamber. The vapor phase processing apparatus according to claim 1 , wherein the vapor phase processing is performed under reduced pressure or normal pressure. The catalyst body is heated to a temperature in the range of 800 to 2000 ° C. and lower than its melting point, and the reaction species generated by catalytic reaction or thermal decomposition reaction of at least a part of the reaction gas with the heated catalyst body or The vapor phase processing apparatus according to claim 1 , wherein the substrate or the film on the substrate held at a temperature of −100 ° C. to 500 ° C. is subjected to vapor phase etching or gas phase ashing by radicals. The vapor phase processing apparatus according to claim 1 , wherein halogen, a compound gas thereof, or an oxidizing gas is used as the reaction gas. The catalyst body is formed of at least one material selected from the group consisting of tungsten, tria-containing tungsten, molybdenum, platinum, palladium, vanadium, silicon, alumina, metal-attached ceramics, and silicon carbide. The vapor phase processing apparatus according to claim 1 . 2. The vapor phase processing apparatus according to claim 1 , wherein the reactive gas is changed to a film forming raw material gas, and a predetermined film is formed on the substrate by supplying the raw material gas.

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