JPH0760793B2 - Method of forming deposited film - Google Patents

Description

The present invention relates to a deposited film forming method in which heat is used as excitation energy to form a photoconductive film, a semiconductor or an insulating film on a predetermined support, and more specifically, thermal energy By the addition of the above, the raw material gas is excited and decomposed, and the amorphous silicon (hereinafter a-
Abbreviated as Si).

Conventionally, as a method of forming a-Si deposited film, SiH ₄ or Si
Glow discharge deposition method and thermal energy deposition method using ₂ H ₆ as a raw material are known. That is, these deposition methods are
This is a method in which SiH ₄ or Si ₂ H ₆ as a source gas is decomposed by electric energy or thermal energy (excitation energy) to form a deposited film of a-Si on a support. It is used for various purposes as a conductive film, a semiconductor, an insulating film, or the like.

However, in the glow discharge deposition method, in which a deposited film is formed under high-power discharge, it is difficult to control reproducible and stable conditions such as the fact that a uniform discharge distribution state cannot always be obtained. The influence of high-power discharge on the film inside is large, it is difficult to secure the uniformity of the electrical and optical characteristics of the formed film and the stability of the quality, the film surface is disturbed during deposition, and the inside of the deposited film Is likely to cause defects. In particular, it was very difficult to uniformly form a thick deposited film by this method in terms of electrical and optical characteristics.

On the other hand, also in the thermal energy deposition method, since a high temperature of 400 ° C. or higher is usually required, the support material used is limited, and in addition, useful bonded hydrogen atoms in desired a-Si are released. Since the probability increases, it is difficult to obtain desired characteristics.

So, as one method to solve these problems,
Attention is focused on a low calorific thermal energy deposition method (thermal CVD) of a-Si using a silicon compound other than SiH ₄ and Si ₂ H ₆ as a raw material.

This low calorific thermal energy deposition method uses low-temperature heating instead of glow discharge or high-temperature heating in the above-described method as excitation energy, and a-Si deposited film is produced at a low energy level. It enables you to do it. Further, the lower the temperature, the easier it is to uniformly heat the raw material gas, and it is possible to perform high-quality film formation while maintaining uniformity, with lower energy consumption compared to the above-mentioned deposition method, and the manufacturing conditions. It has the advantages that control is easy and stable reproducibility is obtained, there is no need to heat the support to a high temperature, and the selectivity with respect to the support is widened.

The present invention has been made in view of the above points, and by performing film formation without generating plasma in the deposition chamber by using low-level thermal energy as excitation energy, high quality is maintained while maintaining high quality. It is an object to provide a thermal energy deposition method capable of forming a deposited film containing silicon atoms at a film rate.

Another object of the present invention is to form a high-quality deposited film that secures uniformity of electrical and optical characteristics and stability of quality even when forming a large-area, thick-film deposited film. To provide a way to do it.

As a result of diligent studies, the present invention has found that these objects have a side chain represented by the general formula: SinH ₂ n ₊₂ (n ≧ 4) as a source gas for forming an a-Si film that is decomposed by thermal energy. It has been completed by finding out what can be achieved by using the chain silane compound having it in a mixed state with a halogen compound.

That is, the deposited film forming method of the present invention is performed by using the general formula; Si _n H in a deposition chamber in which a support held at 150 ° C. to 300 ° C. is placed.
A chain silane compound having a side chain represented by _{2n + 2} (n ≧ 4), a halogen gas, and Group III or V of the periodic table
A gaseous atmosphere is formed with a compound containing an atom belonging to the group, and thermal energy is supplied to the deposition chamber without supplying electrical energy capable of generating plasma to excite the compound, and on the support. It is characterized in that a deposited film containing silicon atoms and atoms belonging to Group III or Group V of the periodic table is formed.

In the method of the present invention, a silicon compound as a raw material for supplying Si and a compound containing these atoms for introducing an atom belonging to Group III or Group V of the periodic table are used as the raw material and formed. The deposited film is a deposited film containing silicon atoms and atoms belonging to Group III or Group V of the periodic table, and can be used for various purposes as a functional film such as a photoconductive film or a semiconductor film.

The raw material for supplying Si used in the method of the present invention is a chain silane compound having a side chain represented by the general formula; SinH ₂ n ₊₂ (n ≧ 4), and has good a-Si deposition. In order to form a film, n in the above formula is 4 to 15, preferably 4 to 10,
It is more desirable that it is 4 to 7.

Examples of such compounds include those represented by the following formula.

However, in the case of a chain silane compound having such a side chain, when heat energy is used as excitation energy, efficient excitation and decomposition cannot be obtained, and a good film formation rate cannot be obtained.

Therefore, in the method of the present invention, in order to more efficiently promote the excitation and decomposition of the chain silane compound having the above side chain by thermal energy, a halogen compound is mixed with the chain silane compound having the side chain. To be done.

The halogen compound mixed in the chain silane compound having the side chain in the method of the present invention is a compound containing a halogen atom, and is excited by thermal energy of the chain silane compound having the side chain, and decomposed. It can be promoted more efficiently. Examples of such a halogen compound include halogen gas such as Cl ₂ , Br ₂ , I ₂ , and F ₂ .

In the method of the present invention, the ratio of the halogen compound mixed with the a-Si film forming raw material compound is a-
Depending on the type of raw material compound and halogen compound for Si film formation, 0.01 to 80 Vol%, preferably 0.1 to 50 Vol%
Used within the range of%.

In the deposited film formed in the method of the present invention, for example, B,
Raw materials used for introducing atoms belonging to Group III of the periodic table such as Al, Ga, In and Tl or Group V such as N, P, As, Sb and Bi include those atoms, A compound that is easily excited and decomposed by energy is used, and examples of such a compound include PH ₃ , P ₂ H ₄ , PF ₃ , PF ₅ , PCl ₃ , AsH ₃ and AsF.
₃ , AsF ₅ , AsCl ₃ , SbH ₃ , SbF ₅ , BiH ₃ , BF ₃ , BCl ₃ , BBr ₃ , B ₂ H ₆ , B ₄ H
Examples thereof include ₁₀ , B ₅ H ₉ , B ₆ H ₁₀ , B ₆ H ₁₂ and AlCl ₃ .

In the method of the present invention, a silicon compound as described above in a gas state and a compound containing an atom belonging to Group III or Group V of the periodic table are introduced into a deposition chamber, and thermal energy is applied to these compounds. When applied, these are excited and decomposed, and a deposited film (a-Si film) containing silicon atoms and atoms belonging to Group III or Group V of the periodic table is formed on the support placed in the deposition chamber.

Next, the application of thermal energy to the silicon compound gas introduced into the deposition chamber is a Joule heat generation element,
It is performed using a high frequency heating means or the like.

The Joule heat generating element may be a heater such as a heating wire or an electric heating plate, and the high frequency heating means may be induction heating or dielectric heating. Explaining an embodiment using the Joule heat generating element, the heater is brought into contact with or close to the back surface of the support to conductively heat the surface of the support to thermally excite and decompose the raw material gas in the vicinity of the surface to decompose the decomposition product to the surface of the support. To deposit.

Alternatively, the heater can be placed near the surface of the support.

Hereinafter, the method of the present invention will be described in detail with reference to FIG.

FIG. 1 is a schematic configuration diagram of a deposited film forming apparatus for forming a functional film such as a photoconductive film made of a-Si, a semiconductor film, or an insulator film on a support.

The deposited film is formed inside the deposition chamber 1.

Reference numeral 3 which is placed inside the deposition chamber 1 is a support table on which a support is arranged.

Reference numeral 4 is a heater for heating the support, and the conductor 4 supplies power to the heater 4. A gas introducing pipe for introducing a raw material gas of a-Si and a gas such as a carrier gas used as necessary into the deposition chamber 1 is connected to the deposition chamber 1. The other end of the gas introducing pipe 17 is connected to gas supply sources 9, 10, 11, 12 for supplying a raw material gas for forming a-Si and a gas such as a carrier gas used as necessary. Corresponding flow meters 15-1, 15-2, 15-3, 15-4 correspond to measure the flow rate of each gas flowing out from the gas supply sources 9, 10, 11, 12 toward the deposition chamber 1. The gas introduction pipes 17-1, 17-2, 17-3, 17-4 are branched.
Valves 14-1, 14-2, 14- are installed before and after each flow meter.
3,14-4, 16-1, 16-2, 16-3, 16-4 are provided, and a predetermined flow rate of gas can be supplied by adjusting these valves. 13-1, 13-2, 13-3, 13-4 are pressure meters for measuring the pressure on the high pressure side of the corresponding flow meter.

The respective gases that have passed through the flow meter are mixed and introduced into the volume chamber 1 under reduced pressure by an exhaust device (not shown). The pressure meter 18 measures the total pressure of the mixed gas.

A gas exhaust pipe 20 is connected to the deposition chamber 1 to reduce the pressure inside the deposition chamber 1 and to exhaust the introduced gas. The other end of the gas exhaust pipe is connected to an exhaust device (not shown).

In the present invention, the number of gas supply sources 9, 10, 11, 12 is appropriately set.
It can be increased or decreased.

That is, when using a single source gas, one gas supply source is sufficient. However, when two kinds of raw material gases are mixed and used, two or more are required when a single raw material gas (catalyst gas, carrier gas or the like) is mixed.

Since some raw materials do not become gas at room temperature but remain liquid, a vaporizer (not shown) is installed when using a liquid raw material. Vaporizers include those that utilize heating and boiling, and those that allow a carrier gas to pass through a liquid raw material. The raw material gas obtained by vaporization is introduced into the deposition chamber 1 through a flow meter.

A typical PIN using the device shown in FIG.
The a-Si deposited film forming method of the present invention will be described in more detail by using an example of a method of forming a diode device.

FIG. 2 is a schematic cross-sectional view for explaining the structure of a typical PIN diode device obtained by the present invention.

21 is a support, 22 and 26 are thin film electrodes, 23 is a P-type a-Si
A layer, 24 is an I-type a-Si layer, 25 is an N-type a-Si layer, 27 is a semiconductor layer, and 28 is a conducting wire. Semi-conductive as the support 21,
An electrically insulating material is preferably used. Examples of the semiconductive support include a plate made of a semiconductor such as Si or Ge.

As the electrically insulating support, a film or sheet of synthetic resin such as polyester, polyethylene, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene and polyamide, glass, ceramics, paper and the like are usually used. It

Particularly, in the method of the present invention, the temperature of the support is 150 to 3
Since the temperature can be set to a relatively low temperature of about 00 ° C., it is made of a material having low heat resistance, which cannot be applied to the conventional glow discharge deposition method or thermal energy deposition method among the materials forming the support. Supports can also be used.

The thin film electrode 22 is, for example, NiCr, Al, Cr, Mo, Au, Ir, Nb, Ta, V, T
Obtained by depositing a thin film such as i, Pt, Pd, In ₂ O ₃ , SnO ₂ , ITO (In ₂ O ₃ + SnO ₂ ) on the support using methods such as vacuum deposition, electron beam deposition, and sputtering. .

The thickness of the electrode 22 is 30 to 5 × 10 ⁴ Å, more preferably 1
It is desirable to set it to 00-5 × 10 ³ Å.

In order to make a predetermined layer among the layers forming the a-Si semiconductor layer 27 N-type or P-type as desired, N-type impurities or P-type impurities are formed during layer formation. It suffices to dope the layer while controlling its amount.

Examples of P-type impurities doped in the semiconductor layer include atoms belonging to Group III of the periodic table, among which, for example, B, Al, G
Preferred examples thereof include a, In, Tl, and the like. Examples of N-type impurities include atoms belonging to Group V of the periodic table, among which, for example, N,
P, As, Sb, Bi and the like are mentioned as preferable ones, but especially B,
Ga, P, Sb, etc. are optimal.

In the present invention, the semiconductor layer 27 is added to impart the desired conductivity type.
The amount of impurities to be doped therein is appropriately determined according to desired electrical and optical characteristics.
In the case of Group I impurities, it may be doped so as to be in the range of 3 × 10 ^{-2 to 4} atomic%, and in the case of impurities of Group V of the periodic table, it is in the range of 5 × 10 ^{-3 to 2} atomic%. Doping so that

In order to dope the predetermined layer in the layers forming the semiconductor layer 27 with the impurities as described above, a raw material for introducing impurities may be introduced into the deposition chamber in a gas state at the time of forming the layer. As such a raw material for introducing impurities, those which can be easily gasified at room temperature and atmospheric pressure in a gas state or at least under layer forming conditions or by a vaporizer are adopted.

As such a raw material substance (impurity gas) for introducing impurities, specifically for introducing N-type impurities, PH ₃ , P ₂ H ₄ , PF ₃ , P
_{F 5, PCl 3, AsH 3} , AsF 3, AsF 5, AsCl 3, SbH 3, SbF 5, BiH 3, whereas P
BF ₃ , BCl ₃ , BBr ₃ , B ₂ H ₆ , B ₄ H ₁₀ , B ₅ H
₉ , B ₆ H ₁₀ , B ₆ H ₁₂ , AlCl _{3 and the} like can be mentioned.

Next, the method for forming the semiconductor layer 27 will be described more specifically.

First, the support 21 having a thin layer of the electrode 22 attached to the surface is placed on the support base 3 in the deposition chamber 1, and the gas in the deposition chamber is exhausted through a gas exhaust pipe 20 by an exhaust device (not shown) to reduce the pressure. . The pressure in the deposition chamber under reduced pressure is preferably 5 × 10 ^-5 Torr or less, and more preferably 10 ^-6 Torr or less.

When the pressure inside the deposition chamber 1 is reduced, the heater 4 is energized to heat the support 3 to a predetermined temperature. The temperature of the support at this time is 150 to 300 ° C, preferably 200 to 250 ° C.

Thus, in the method of the present invention, when a chain silane compound having a side chain, a halogen gas, and a compound containing an atom belonging to Group III or Group V of the periodic table are mixed, the side chain is In order to efficiently promote the excitation and decomposition of the chain silane compound by thermal energy, the temperature of the support must be 150 ° C or higher, and even if the deposited film is formed below 150 ° C, it becomes a polymer. Therefore, it is considered that a dense deposited film having desired characteristics cannot be obtained. on the other hand,
It is considered that if the temperature of the support is not lower than 300 ° C., the probability that useful bonded hydrogen atoms in the a-Si film formed will be released will increase and the film properties will deteriorate, making it impossible to obtain the desired properties. Further, since the high temperature heating of the support as in the glow discharge deposition method or the thermal energy deposition method using SiH ₄ or Si ₂ H ₆ as a raw material is not required, the energy consumption required for the deposited film formation is also reduced. You can save.

Next, in order to stack the P-type a-Si layer on the thin-layer electrode 22 on the support 21, the valve 14-1 of the source 9 filled with the Si-supplying raw material gas as listed above. , 16-1 and valves 14-5, 16- of source 29 filled with halogen compounds
5 and the valves 14-2 and 16-2 of the supply source 10 in which the P-type impurity gas is stored are opened, respectively, and the Si supply source gas and the P-type impurity gas are mixed at a predetermined mixing ratio. The gas is sent into the deposition chamber 1.

At this time, the flow rate is adjusted while measuring with the corresponding flow meters 15-1, 15-2, 15-5. The flow rate of raw material gas is 10 to 1000
SCCM Suitably the range of 20-500 SCCM is desirable.

The flow rate of the P-type impurity gas is determined by the flow rate of the source gas × the doping concentration.

However, since the amount of the impurity gas mixed in is extremely small, in order to easily control the flow rate, the impurity gas is usually added.
It is used after being stored in a state of being diluted with H ₂ gas or the like to a predetermined concentration.

The pressure of the mixed gas is 10 ^-2 ~100Torr the deposition chamber 1, preferably it is desirable that maintained in the range of 10 ^-2 ~1Torr.

In this way, thermal energy is applied to the raw material gas flowing near the surface of the support 2, thermal excitation and thermal decomposition are promoted, and a-Si as a product substance and a trace amount of P-type impurity atoms are present on the support. Be deposited on.

Decomposition products other than a-Si and P-type impurity atoms and surplus raw material gas not decomposed are discharged through the gas exhaust pipe 20, while new raw material mixed gas is continuously supplied through the gas introduction pipe 17. Then, a P-type a-Si layer 23 is formed. P-type a-Si 100~10 ⁴ Å as the layer thickness, preferably it is preferably in the range of 300～2000A.

Next, the valves 14-1, 16-1, 14 connected to the gas supply sources 9, 10 are connected.
-2, 16-2, 14-5, 16-5 are all closed, and the introduction of gas into the deposition chamber 1 is stopped. After exhausting the gas in the deposition chamber by driving an exhaust device (not shown), the valves 14-1, 16-1, 14 are again
-5 and 16-5 are opened, and the Si supply source gas is introduced into the deposition chamber 1. Suitable flow rate conditions and pressure conditions in this case are the same as the conditions when forming the P-type a-Si layer 23.

In this way, the undoped or I-type a-Si layer 24 is formed.

The thickness of the I-type a-Si layer is 500 to 5 × 10 ⁴ Å, preferably 1000
The range of ~ 10,000Å is desirable.

Next, the valves 14-3 and 16-3 connected to the gas supply source 11 in which the N-type impurity gas is stored are opened, and the N-type impurity gas is introduced into the deposition chamber 1.

The flow rate of the N-type impurity gas is determined from the flow rate of the Si supply source gas × the doping concentration, as in the case of determining the flow rate of the P-type impurity gas.

In the same manner as when forming the P-type a-Si layer 23, thermal energy is applied to the raw material gas flowing near the surface of the support 2 to promote thermal excitation and thermal decomposition, and the decomposition product a-Si is supported. An N-type a-Si layer 25 is formed by depositing a small amount of N-type impurity atoms, which is a decomposition product, on the deposit.

The thickness of the N-type a-Si layer 25 is 100 to 10 ⁴ Å, preferably 300
A range of up to 2,000Å is desirable.

In forming the P-type and N-type a-Si layers as described above, the Si-supplying raw material gas and the impurity-introducing gas used in the method of the present invention are, as described above, thermal energy. Is easily excited and decomposed, so that a high layer formation rate of about 5 to 50 Å / sec can be obtained.

Finally, the thin-layer electrode 26 is formed on the N-type a-Si layer 25 in the same layer thickness as the thin-layer electrode 22 by the same method as that for forming the thin-layer electrode 22 to complete the PIN diode device. .

The PIN diode device formed in this manner satisfied the predetermined characteristics and quality.

According to the method of the present invention, in addition to the formation of the semiconductor layer of the PIN type diode device described above, a single-layer or multi-layer a-Si layer having desired electrical / optical characteristics is formed. Can be formed. Further, in the example described above, the deposited layer was formed under reduced pressure, but the present invention is not limited to this, and the method of the present invention can be carried out under normal pressure or under increased pressure as desired.

According to the method of the present invention as described above, the heat energy of a low calorie is used as the excitation energy, and the raw material gas that is easily excited and decomposed by the heat energy is used. A- at the level
It has become possible to form a Si deposited layer, and it has become possible to form an a-Si deposited layer having excellent uniformity of electrical and optical characteristics and excellent quality stability. Therefore, in the method of the present invention, a support made of a material having low heat resistance, which cannot be applied to the conventional glow discharge deposition method or thermal energy deposition method, can be used, and the high temperature of the support can be used. It has become possible to save the energy consumption required for heating.

Further, although heat energy is used as the excitation energy, since the low heat quantity is applied instead of the high heat quantity, the energy can always be uniformly applied to the predetermined space occupied by the source gas to which the energy is applied, and therefore the deposited film It has become possible to form the film accurately and uniformly.

Hereinafter, the present invention will be specifically described with reference to examples.

Example 1 Using the apparatus shown in FIG. 1, the above-mentioned silane compound No. 1 was used as a raw material for supplying Si, and I ₂ was used as a halogen compound.
Was used to form a P-type a-Si layer doped with B atoms using B ₂ H ₆ as a P-type impurity introducing gas as follows.

First, a support (polyethylene terephthalate) is set on the support base 3 in the deposition chamber 1, the pressure in the deposition chamber 1 is reduced to 10 ⁻⁶ Torr by an exhaust device (not shown) through the gas exhaust pipe 20, and the heater 4 is energized. And maintain the support temperature at 230 ℃,
Next, the valves 14-1, 16-1 of the raw material supply source 9 filled with the silane compound No. 1 and the valve 14- of the supply source 29 filled with I ₂
5,16-5 further diluted by H ₂ (1000ppm H ₂ dilution) are P-type impurity introduced gas B ₂ H ₆ material supply source filled 10
The valves 14-2 and 16-2 were opened and the raw material mixed gas was introduced into the deposition chamber 1.

At this time, the silane compound No. 1 was adjusted to 150 SCCM, the PH ₃ gas was adjusted to 40 SCCM, and the I ₂ was adjusted to 10 SCCM while measuring the corresponding flow meters 15-1, 15-2, 15-5. .

Next, the pressure in the deposition chamber was kept at 0.1 Torr, and the P thickness of 400 Å was used.
The type a-Si layer 3 (B atomic content 5 × 10 ⁻³ atomic%) is
It was deposited on the support 2 at a film forming rate of Å / sec. The thermal energy was uniformly applied to the gas flowing near the entire surface of the support 2 arranged in the deposition chamber 1. At this time, decomposition products other than a-Si and B atoms, surplus raw material gas not decomposed, and the like are discharged through the gas exhaust pipe 20, while new raw material mixed gas is introduced into the gas introduction pipes 17 and 30.
Continuously fed through.

Thus formed by the method of the present invention, a-Si
The evaluation of the layers was performed by further forming a comb-shaped Al gap electrode (length: 250 μ, on each of the a-Si layers formed on the substrate).
Width 5mm), dark current is measured, and dark conductivity σ
_This was done by determining _d .

The gap electrode is a formed as described above.
− Put the Si layer in a vapor deposition tank, depressurize the tank once to a vacuum degree of 10 ^-6 Torr, adjust the vacuum degree to 10 ^-5 Torr, and vapor deposition rate 20 Å / sec with a layer thickness of 1500 Å. , Al was evaporated on the a-Si layer, and this was etched and patterned using a pattern mask having a predetermined shape.

The obtained dark conductivity σ _d is shown in Table 1.

Examples 2 and 3 A P-type a-Si film was formed in the same manner as in Example 1 except that Br ₂ (Example 2) or Cl ₂ (Example 3) was used as the halogen compound. The obtained a-Si film was used in Example 1.
It evaluated similarly to. The evaluation results are shown in Table 1.

Examples 4 to 9 As a raw material and a halogen compound for forming an a-Si deposited film,
Examples except that the above-mentioned silicon compounds No. 2, No. 3 and I ₂ , Br ₂ , Cl ₂ were individually combined and the halogen gas flow rates were set as shown in Tables 1 and 2 An a-SI film was deposited in the same manner as 1. The obtained a-Si film was evaluated in the same manner as in Example 1. The evaluation results are shown in Tables 1 and 2.

Comparative Examples 1 to 3 Compounds No. 1, No. 2 and N described above as raw materials for supplying a-Si
An a-Si film was deposited in the same manner as in Example 1 except that the halogen compound was not used. The obtained a-
The Si film was evaluated in the same manner as in Example 1. Table 1 shows the evaluation results
And shown in Table 2.

Examples 10 to 18 As raw materials for a-Si supply and halogen compounds, the above compounds No. 1, No. 2, No. 3 and I ₂ , Br ₂ , Cl ₂ were used individually in combination, and impurities were used. N-type PH ₃ as gas for introduction
Is used, and the halogen gas flow rates are shown in Tables 3 and 4.
In the same manner as in Example 1 except that the setting as shown in FIG.
-Si film was deposited. The obtained a-Si film was evaluated in the same manner as in Example 1. The evaluation results are shown in Tables 3 and 4.

Comparative Examples 4 to 6 Silane compound described above as a raw material for forming a-Si deposited film
An a-Si film was formed in the same manner as in Example 1 except that No. 1, No. 2 and No. 3 were used, a halogen compound was not used, and N-type PH ₃ was used as an impurity introduction gas. Deposited.
The obtained a-Si layer was evaluated in the same manner as in Example 1. The evaluation results are shown in Tables 3 and 4.

Comparing the corresponding examples using the same kind of a-Si film source, the film formation rate is about 2-3 times higher when B ₂ H ₆ is doped than when it is mixed with a halogen compound. Was increased, and when PH ₃ was doped, the film formation rate was increased by about 2 to 3 times. The rate of acceleration of the film formation rate depending on the type of halogen is generally larger in the order of Cl ₂ , Br ₂ and I ₂ .

Also, the electrical characteristics were improved.

Example 19 Using the apparatus shown in FIG. 1 and using the above-mentioned silicon compound No. 1 as a raw material for supplying Si, a PIN diode device as shown in FIG. 2 was formed as follows. Was carried out.

First, support 21 [polyethylene naphthalate transparent conductive film with 1000Å evaporated ITO (Indium Tin Oxide)]
Was set on the support 3 in the deposition chamber 1, and the silicon compound No. 1, B ₂ H ₆ gas and I ₂ gas were supplied from the raw material supply sources 9 and 29 under the same operating conditions as in Example 1. Then, the P-type a-Si layer 23 was formed.

Next, when the thickness of the P-type a-Si layer 23 reaches 400 Å, the valves 14-1 and 16 connected to the gas supply sources 9, 10 and 29 are connected.
-1,14-2,16-2,14-5,16-5 are all closed, and the introduction of gas into the deposition chamber 1 is stopped. After exhausting gas in the deposition chamber by driving an exhaust device (not shown), the valve 14-1,
Open 16-1,14-5,16-5, Si supply silane compound No.1
Is introduced into the deposition chamber 1 at a flow rate of 150 SCCM and I ₂ gas at a flow rate of 10 SCCM, and a non-doped or I-type a-Si layer 24 (layer thickness: 5000
Å) was formed at the same speed as when the P-type a-Si layer 23 was formed.

Next, the valves 14-3 and 16-3 connected to the gas supply source 11 in which the N-type impurity introduction gas PH ₃ diluted with H ₂ (dilution rate 0.05 mol%) is stored are opened, and the inside of the deposition chamber 1 is opened. To PH
Introducing ₃ gases and using the operating conditions in Example 13, P
Atomically doped N-type a-Si layer 25 (layer thickness 400 Å)
A semiconductor layer 27 composed of three a-Si layers 23, 24, 25 was formed by depositing on the I-type a-Si layer 24 at the same rate as when forming the type a-Si layer 23.

A vacuum deposition method (pressure of 1 × 10 ⁻⁵⁾ was further performed on the PIN type a-Si semiconductor layer 27 thus formed by the method of the present invention.
Torr) is used to stack Al thin film electrodes with a thickness of 1000Å
Completed N-type diode device.

Rectification characteristics (ratio of forward current and reverse current at a voltage of 1 V) of the PIN diode device (area: 1 cm ² ) formed in this embodiment, n value (current formula J = P-N junction) J {ex
n value in p (eV / nkT) -1}) was evaluated. The results are shown in Table 5.

Examples 20 to 21 As the a-Si supply gas and the halogen compound, each of the above-mentioned silane compounds No. 1, No. 2, No. 3 and I ₂ , Br ₂ , Cl ₂ was used in combination individually, and halogen was used. A PIN-type a-Si semiconductor layer having a three-layer structure was formed in the same manner as in Example 19 except that the gas flow rates were set as shown in Tables 5 and 6, and a PIN-type diode device was prepared. The rectification characteristics and n value of the created PIN diode device were evaluated in the same manner as in Example 19. The results are shown in Tables 5 and 6.

Comparative Examples 7 to 9 Silane compound No. described above as a-Si deposition film supply gas.
A PIN-type a-Si having a three-layer structure in the same manner as in Example 19 except that No. 1, No. 2 and No. 3 were used and no halogen compound was used.
A semiconductor layer was formed to create a PIN diode device. The rectification characteristics and n value of the created PIN diode device were evaluated in the same manner as in Example 19. The results are shown in Tables 5 and 6.

Summarizing the results of Examples 19 to 27 and Comparative Examples 7 to 9 described above, the rectification characteristics of the PIN diode devices formed in Examples 19 to 27 are as low as 50 to 100 ° C. at a support temperature, When the same kind of a-Si supply gas was used, it was better when the halogen gas was used than when it was not.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an example of a deposited film forming apparatus used in the method of the present invention, and FIG. 2 is a schematic sectional view of a PIN diode device that can be formed by the method of the present invention. 1: Deposition chamber, 2, 21: Support, 3: Support, 4: Heater, 5: Conductor, 6-1, 6-2, 6-3: Gas flow, 9, 10, 11, 12: Gas Supply source, 13-1, 13-2, 13-3, 13-4, 18: Pressure meter, 14
-1,14-2,14-3,14-4,16-1,16-2,16-3,16-4,21:
Valve, 15-1, 15-2, 15-3, 15-4: Flow meter, 1
7,17-1,17-2,17-3,17-4: Gas inlet pipe, 20: Gas exhaust pipe, 22,26: Thin film electrode, 23: P-type a-Si layer, 24: I-type a- Si
Layer, 25: N-type a-Si layer, 27: semiconductor layer, 28: conducting wire

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Masahiro Haruta 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hiroshi Hirai 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Ken Eguchi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Takashi Nakagiri 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. ( 56) References JP 58-158646 (JP, A) Appl. Phys. Lett. , 39 [5], ('81 -9-1), PP. 436-438

Claims (1)

[Claims] 1. A chain silane compound having a side chain represented by the general formula: Si _n H _{2n + 2} (n ≧ 4) in a deposition chamber in which a support kept at 150 ° C. to 300 ° C. is arranged. And a halogen gas and a compound containing an atom belonging to Group III or Group V of the periodic table to form a gaseous atmosphere, and thermal energy is supplied to the deposition chamber without supplying electric energy capable of generating plasma. Is supplied to excite the compound to form a deposited film containing silicon atoms and atoms belonging to Group III or Group V of the periodic table on the support.