JP6012933B2 - Substrate processing apparatus, semiconductor device manufacturing method, and substrate processing method - Google Patents

Description

  The present invention relates to a substrate processing apparatus and a semiconductor device manufacturing method.

  In the manufacturing process of a semiconductor device, a substrate processing apparatus is used that heats a substrate and performs processing such as nitriding, oxidation, annealing, and the like. Such a substrate processing apparatus includes, for example, a substrate support unit that is provided in a processing chamber for processing a substrate and supports the substrate, and a heating unit that heats the substrate, and places the substrate carried into the processing chamber on the substrate support unit. The substrate was processed while being heated by the heating unit. Such a heating unit may be provided, for example, in the substrate support unit or in the upper part of the processing chamber (for example, Patent Document 1).

JP 2009-088348 A

  In the substrate processing apparatus including the heating unit as described above, it is conceivable to heat the substrate from various directions such as from the substrate support unit side, the upper side of the processing chamber, or both sides. However, when the substrate is carried into the processing chamber and transferred to the substrate support portion, for example, only one side (lower surface) of the substrate comes into contact with the substrate support portion. For this reason, regardless of the direction of heating, the contact surface (lower surface) with the substrate support portion and the other non-contact surface (upper surface) have different easiness of heating. In some cases, the temperature rate was different. As a result, the temperature uniformity of the substrate may be reduced.

  An object of the present invention is to provide a substrate processing apparatus and a semiconductor device manufacturing method capable of increasing the temperature of a substrate at a high speed while improving the temperature uniformity of the substrate.

  According to an aspect of the present invention, a processing chamber for processing a substrate, a first substrate support portion for temporarily supporting the substrate carried into the processing chamber, and the first substrate provided in the processing chamber. A second substrate support unit on which the substrate is transferred from the support unit; a heating unit that heats the substrate carried into the processing chamber; a gas supply unit that supplies a gas into the processing chamber; and the second substrate Above the support part, the substrate carried into the processing chamber is supported away from the second substrate support part by the first substrate support part, and the gas is supplied into the processing chamber by the gas supply part, The substrate is heated by the heating unit in a state where the pressure in the processing chamber is higher than the pressure at the time of loading the substrate, and after a predetermined time has elapsed, the first substrate support unit to the second substrate support unit The substrate is transferred to and heated. The so as to process the substrate while heating the substrate, the first substrate supporting portion, wherein a heating unit and a control unit for controlling the gas supply unit, a substrate processing apparatus having a is provided by.

According to another aspect of the present invention, the second substrate provided in the processing chamber by the step of carrying the substrate into the processing chamber for processing the substrate and the first substrate support portion that temporarily supports the substrate. Above the support part, the substrate carried into the processing chamber is supported apart from the second substrate support part, gas is supplied into the processing chamber by a gas supply part, and the pressure in the processing chamber is carried into the substrate. A step of heating the substrate by a heating unit that heats the substrate carried into the processing chamber in a state where the pressure is higher than the pressure in the step of performing the second step from the first substrate support unit after a predetermined time has elapsed. Manufacturing a semiconductor device, comprising: transferring the substrate to a substrate support portion; processing the substrate while heating the substrate by the heating portion; and unloading the substrate from the processing chamber. Method proposed It is.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the substrate processing apparatus and semiconductor device which can heat up a board | substrate at high speed, improving the temperature uniformity of a board | substrate are provided.

It is a figure of the deformation | transformation magnetron type | mold plasma processing apparatus as a substrate processing apparatus which concerns on 1st Embodiment of this invention, Comprising: (a) is sectional drawing which shows the mode at the time of carrying in a board | substrate, (b) is a process of a board | substrate. It is sectional drawing which shows the mode of time. It is a schematic diagram which shows the gas exhaust part with which the substrate processing apparatus which concerns on 1st Embodiment of this invention is provided. It is a figure of the gas exhaust part with which the substrate processing apparatus which concerns on 2nd Embodiment of this invention is provided, Comprising: (a) is a schematic diagram which shows an example of a gas exhaust part, (b) is another example of a gas exhaust part. It is a schematic diagram which shows. It is explanatory drawing about the sample which compares the application presence or absence of the manufacturing method of the semiconductor device which concerns on 1st Embodiment of this invention, Comprising: (a) is a flowchart which shows the preparation procedure of a sample, (b) is a sample. It is a graph which shows the film thickness of a natural oxide film.

<One Embodiment of the Present Invention>
(1) Configuration of Substrate Processing Apparatus A substrate processing apparatus according to a first embodiment of the present invention will be described below with reference to FIG. FIG. 1 is a view of a modified magnetron type plasma processing apparatus as a substrate processing apparatus according to the present embodiment, wherein (a) is a cross-sectional view showing a state when a substrate is carried in, and (b) is a processing of the substrate. It is sectional drawing which shows the mode of time.

  The substrate processing apparatus according to the present embodiment performs plasma processing on a wafer 200 such as a silicon (Si) substrate using a modified magnetron type plasma source that generates high-density plasma by an electric field and a magnetic field. This is a modified magnetron type plasma processing apparatus (hereinafter referred to as MMT apparatus 100). The MMT apparatus 100 is configured to carry a wafer 200 into a processing chamber 201 that maintains hermeticity, and generate a magnetron discharge by applying a high-frequency voltage to various gases supplied into the processing chamber 201 under a certain pressure. Has been. According to the MMT apparatus 100, for example, a processing gas or the like is excited by such a mechanism to perform diffusion processing such as oxidation or nitridation on the wafer 200, form a thin film, or etch the surface of the wafer 200. Various plasma treatments can be performed.

(Processing room)
The MMT apparatus 100 includes a processing furnace 202 that performs plasma processing on the wafer 200. The processing furnace 202 is provided with a processing container 203 that constitutes a processing chamber 201. The processing container 203 includes a dome-shaped upper container 210 that is a first container and a bowl-shaped lower container 211 that is a second container. The processing chamber 201 is formed by covering the upper container 210 on the lower container 211. The upper container 210 is made of a non-metallic material such as aluminum oxide (Al ₂ O ₃ ) or quartz (SiO ₂ ), for example, and the lower container 211 is made of aluminum (Al), for example.

A gate valve 244 is provided on the lower side wall of the lower container 211. The gate valve 244 is configured to be able to carry the wafer 200 into the processing chamber 201 using a transfer mechanism (not shown) or to carry the wafer 200 out of the processing chamber 201 when it is open. Yes. The gate valve 244 is configured to be a gate valve that maintains the airtightness in the processing chamber 201 when the gate valve 244 is closed.

(Susceptor)
In the center of the bottom side of the processing chamber 201, a susceptor 217 is disposed as a second substrate support unit that supports the wafer 200. The susceptor 217 is made of a non-metallic material such as aluminum nitride (AlN), ceramics, or quartz, for example, and is configured to reduce metal contamination on a film or the like formed on the wafer 200. .

  Inside the susceptor 217, a heater 217b as a heating unit is integrally embedded. The heater 217b is configured to heat the surface of the wafer 200 to, for example, about 25 ° C. to 700 ° C. when electric power is supplied.

  The susceptor 217 is electrically insulated from the lower container 211. An impedance adjustment electrode 217c is provided inside the susceptor 217. The impedance adjustment electrode 217c is grounded via an impedance variable mechanism 274 as an impedance adjustment unit. The impedance adjustment electrode 217c functions as a second electrode for a cylindrical electrode 215 serving as a first electrode described later. The impedance variable mechanism 274 includes a coil and a variable capacitor. By controlling the inductance and resistance of the coil and the capacitance value of the variable capacitor, the potential (bias voltage) of the wafer 200 is controlled via the impedance adjustment electrode 217c and the susceptor 217. ) Can be controlled.

  The susceptor 217 is provided with a susceptor lifting mechanism 268 that lifts and lowers the susceptor 217. Further, the susceptor 217 is provided with a through hole 217 a, while a wafer push-up pin 266 as a first substrate support is provided on the bottom surface of the lower container 211. The through holes 217a and the wafer push-up pins 266 are provided at least at three locations at positions facing each other. As shown in FIG. 1A, when the susceptor 217 is lowered by the susceptor elevating mechanism 268, the wafer push-up pin 266 penetrates (through) the through-hole 217a without contacting the susceptor 217. The wafer 200 loaded into the processing chamber 201 is temporarily supported by the wafer push-up pins 266. Further, as shown in FIG. 1B, when the susceptor 217 is raised by the susceptor lifting mechanism 268, the wafer 200 is transferred from the wafer push-up pins 266 to the susceptor 217.

(Lamp heating unit)
A light transmission window 278 is provided above the processing chamber 201, that is, on the upper surface of the upper container 210, and a lamp heating unit 280 as a lamp heating device is installed outside the reaction container 203 on the light transmission window 278. . The lamp heating unit 280 is provided at a position facing the susceptor 217 and is configured to heat the wafer 200 from above the wafer 200. By turning on the lamp heating unit 280, the wafer 200 can be heated in a shorter time than the heater 217b. Further, by using the heater 217b in combination, the temperature of the substrate surface can be set to 900 ° C., for example.

(Gas supply part)
A shower head 236 is provided above the processing chamber 201, that is, above the upper container 210. The shower head 236 includes a cap-shaped lid 233, a gas inlet 234, a buffer chamber 237, an opening 238, a shielding plate 240, and a gas outlet 239, and various gases are introduced into the processing chamber 201. It is configured so that it can be supplied. The buffer chamber 237 is configured as a dispersion space for dispersing the gas introduced from the gas introduction port 234.

The gas inlet 234 has a downstream end of a hydrogen-containing gas supply pipe 232a that supplies hydrogen (H ₂ ) gas as a hydrogen-containing gas, and a nitrogen-containing gas supply that supplies nitrogen (N ₂ ) gas as a nitrogen-containing gas. It connects so that the downstream end of the pipe | tube 232b may join. The hydrogen-containing gas supply pipe 232a is provided with an H ₂ gas supply source 250a, a mass flow controller 252a as a flow rate control device, and a valve 253a as an on-off valve in order from the upstream side. The nitrogen-containing gas supply pipe 232b is provided with an N ₂ gas supply source 250b, a mass flow controller 252b as a flow rate control device, and a valve 253b as an on-off valve in order from the upstream side. A valve 254 is provided on the downstream side where the hydrogen-containing gas supply pipe 232a and the nitrogen-containing gas supply pipe 232b merge, and is connected to the upstream end of the gas inlet 234 via the gasket 203b. By opening the valves 253a, 253b, and 254, the flow rates of the respective gases are adjusted by the mass flow controllers 252a and 252b, and the hydrogen-containing gas and the nitrogen-containing gas are introduced into the processing chamber 201 via the gas supply pipes 232a and 232b. It is configured so that it can be supplied.

Mainly, a shower head 236 (cover 233, gas inlet 234, buffer chamber 237, opening 238, shielding plate 240, gas outlet 239), hydrogen-containing gas supply pipe 232a, nitrogen-containing gas supply pipe 232b, H ₂ gas A gas supply unit according to this embodiment is configured by the supply source 250a, the N ₂ gas supply source 250b, the mass flow controllers 252a and 252b, and the valves 253a, 253b, and 254.

(Gas exhaust part)
A gas exhaust chamber 201 a for exhausting gas from inside the processing chamber 201 is provided on the side wall of the lower container 211. The upstream end of the gas exhaust pipe 231a is connected to the gas exhaust chamber 201a. As shown in FIG. 2, the gas exhaust chamber 201a is provided with a diaphragm gauge 241a as a pressure control sensor such as a capacitance manometer. The diaphragm gauge 241a is configured to be able to measure up to 2 Torr (266 Pa) as an upper limit pressure, for example. The gas exhaust pipe 231a includes, in order from the upstream side, an APC (Auto Pressure Controller) 242 as a pressure regulator (pressure regulator), a turbo molecular pump 246a as a vacuum exhaust device, a main valve 243a as an on-off valve, and a vacuum exhaust device A dry pump 246b is provided.

  The APC 242 can be evacuated and stopped by opening and closing the valve, and further, the opening and closing of the processing chamber 201 can be adjusted by adjusting the opening of the valve based on pressure information measured by the diaphragm gauge 241a. It is a valve. The substrate processing using the MMT apparatus 100 is performed under a pressure of 266 Pa or less, more preferably 240 Pa or less, for example. By setting the upper limit pressure of the diaphragm gauge 241a to, for example, 2 Torr (266 Pa), the measurement accuracy in the pressure region of the substrate processing can be improved, and high pressure controllability and resolution can be obtained during the substrate processing.

  As the turbo molecular pump 246a, for example, a broadband type can be used. In this case, the turbo molecular pump 246a is configured to be capable of supporting up to 400 Pa as the maximum pressure upstream of the turbo molecular pump 246a, that is, the primary side of the turbo molecular pump 246a. .

A slow exhaust line is provided on the downstream side of the turbo molecular pump 246a, that is, on the secondary side of the turbo molecular pump 246a. Specifically, the upstream end of the gas exhaust pipe 231b is connected between the turbo molecular pump 246a and the main valve 243a of the gas exhaust pipe 231a. A downstream end of the gas exhaust pipe 231b is connected between the main valve 243a of the gas exhaust pipe 231a and the dry pump 246b. For example, a 3/8 inch pipe is used for the gas exhaust pipe 231b, and a slow exhaust valve 243b as an on-off valve is provided.

  The gas exhaust according to the present embodiment is mainly configured by the gas exhaust chamber 201a, the diaphragm gauge 241a, the gas exhaust pipe 231a, the APC 242, the turbo molecular pump 246a, the main valve 243a, the dry pump 246b, the gas exhaust pipe 231b, and the slow exhaust valve 243b. The part is composed.

(Plasma generator)
A cylindrical electrode 215 as a first electrode is provided on the outer periphery of the processing chamber 201, that is, outside the side wall of the upper container 210 so as to surround the processing chamber 201. The cylindrical electrode 215 is formed in a cylindrical shape, for example, a cylindrical shape. The cylindrical electrode 215 is connected to a high-frequency power source 273 having a frequency of 13.56 MHz, for example, to which high-frequency power is applied via a matching unit 272 that performs impedance matching.

  Upper and lower magnets 216a and 216b are attached to upper and lower ends of the outer surface of the cylindrical electrode 215, respectively. Both the upper magnet 216a and the lower magnet 216b are composed of permanent magnets formed in a cylindrical shape, for example, a cylindrical shape. The upper magnet 216a and the lower magnet 216b have magnetic poles on the surface side facing the processing chamber 201 and on the opposite surface side. The direction of the magnetic poles of the upper magnet 216a and the lower magnet 216b is arranged to be opposite to each other. That is, the magnetic poles on the surface side of the upper magnet 216a and the lower magnet 216b facing the processing chamber 201 are different from each other. Thereby, magnetic field lines in the cylindrical axis direction are formed along the inner surface of the cylindrical electrode 215.

  A magnetic field is generated by the upper magnet 216a and the lower magnet 216b, and various gases are introduced into the processing chamber 201. Then, high frequency power is supplied to the cylindrical electrode 215 to form an electric field, so that FIG. ), A magnetron discharge plasma is generated in the plasma generation region 224 in the processing chamber 201. By causing the above-described electromagnetic field to circulate around the emitted electrons, the ionization rate of plasma is increased, and a long-life and high-density plasma can be generated.

  The cylindrical electrode 215, the upper magnet 216a and the lower magnet 216b are made of metal that effectively shields the electromagnetic field so that the electromagnetic field formed by these does not adversely affect other devices and the external environment. A shielding plate 223 is provided.

  The plasma generation unit according to this embodiment is mainly configured by the cylindrical electrode 215, the matching unit 272, the high-frequency power source 273, the upper magnet 216a, and the lower magnet 216b.

(Substrate transfer port)
Further, the MMT apparatus 100 is provided with a substrate transfer chamber opening (not shown) outside the processing container 203 via a gate valve 244. The substrate transfer chamber port communicates with a substrate transfer chamber (not shown) connected to the MMT apparatus 100. The substrate transfer chamber is provided with a transfer mechanism (not shown) so that the substrate can be transferred into and out of the processing chamber 201. Note that the temperature in the substrate transfer chamber is kept at, for example, room temperature, and the pressure is 0.1 Pa or more and 266 Pa or less, for example, about 100 Pa. As a result, even if particles are generated in the substrate transfer chamber, it is possible to suppress the particles from flying up due to the substrate loading / unloading operation by the transfer mechanism.

(Control part)
The controller 121 as a control unit includes a diaphragm gauge 241a, an APC 242, a turbo molecular pump 246a, a dry pump 246b, and a main valve 243 through a signal line A.
a, a slow exhaust valve 243b, a susceptor raising / lowering mechanism 268 through a signal line B, a heater 217b and an impedance variable mechanism 274 through a signal line C, a gate valve 244 through a signal line D, a matching unit 272 and a high-frequency power source through a signal line E 273, the mass flow controllers 252a and 252b and the valves 253a, 253b and 254 through the signal line F, and the lamp heating unit 280 through the signal line G, respectively.

(2) Substrate Processing Step Next, the substrate processing step according to the present embodiment will be described. The substrate processing process according to this embodiment is performed by the above-described MMT apparatus 100 as one process of a semiconductor device manufacturing process, for example. In the substrate processing step according to the present embodiment, the temperature of the wafer 200 is raised from the susceptor 217 side by the heater 217b as a heating unit built in the susceptor 217 as the second substrate support unit, and while heating, for example, A predetermined substrate process, for example, a nitriding process is performed on the wafer 200 made of silicon (Si). In the following description, the operation of each part constituting the MMT apparatus 100 is controlled by the controller 121.

(Substrate loading process)
First, the pressure in the process chamber 201 is set to the same pressure as that of a substrate transfer chamber (not shown) adjacent to the process chamber 201, for example, 100 Pa, and the wafer 200 is transferred from the substrate transfer chamber into the process chamber 201. Specifically, the inside of the processing chamber 201 is evacuated using the turbo molecular pump 246a and the dry pump 246b, and a gas inert to the processing performed on the wafer 200 or the wafer 200 is supplied into the processing chamber 201. Then, the pressure in the processing chamber 201 is adjusted to substantially the same pressure as that of the substrate transfer chamber. Next, the susceptor 217 is lowered to the transfer position of the wafer 200, and the wafer push-up pins 266 are passed through the through holes 217 a of the susceptor 217. As a result, the wafer push-up pins 266 protrude from the upper surface of the susceptor 217 by a predetermined height, for example, about 0.5 mm to 3.0 mm. Subsequently, the gate valve 244 is opened, and the wafer 200 is loaded into the processing chamber 201 from the substrate transfer chamber using a transfer mechanism not shown in the drawing. As a result, the wafer 200 is supported in a horizontal posture on the wafer push-up pins 266 protruding from the upper surface of the susceptor 217. When the wafer 200 is loaded into the processing chamber 201, the transfer mechanism is retracted out of the processing chamber 201, the gate valve 244 is closed, and the processing chamber 201 is sealed.

  Electric power is supplied to the heater 217b in advance, and the heater 271b and the susceptor 217 are heated to a predetermined temperature within a range of, for example, 25 ° C. or more and 700 ° C. or less and 900 ° C. or less when the lamp heating unit 280 is used in combination. Here, when the loaded wafer 200 is immediately transferred onto the susceptor 217, the contact surface of the wafer 200 with the susceptor 217 is more easily heated, and there is a difference in the temperature increase rate with the opposite surface of the wafer 200. End up. As a result, the temperature uniformity of the wafer 200 may be reduced. A decrease in temperature uniformity of the wafer 200 is likely to occur at, for example, 700 ° C. or higher.

  Therefore, in the present embodiment, the following substrate heating step is performed before the wafer 200 is transferred to the susceptor 217. That is, as described below, the present inventors support the wafer 200 away from the susceptor 217 by the wafer push-up pins 266, and keep the temperature uniformity of the wafer 200 good by heat radiation from the susceptor 217. The idea was that the temperature would rise gradually. However, with such a technique, there is a concern that it takes a long time for the wafer 200 to be heated to a predetermined temperature.

  For this reason, the present inventors have further studied to raise the temperature of the wafer 200 at a high speed. Hereinafter, based on the knowledge obtained by the present inventors from such research results, a method for increasing the temperature of the wafer 200 at a high speed while improving the temperature uniformity of the wafer 200 will be described.

(Substrate heating process)
In the substrate temperature raising step, the temperature of the wafer 200 carried into the processing chamber 201 is raised. Specifically, for example, when the lamp heating unit 280 is used in combination with the heater 217b at 25 ° C. or more and 700 ° C. or less, the wafer push-up pins 266 are disposed above the susceptor 217 heated to a predetermined temperature within a range of 900 ° C. or less. Thus, the wafer 200 is supported away from the susceptor 217. In addition, while exhausting the inside of the processing chamber 201 through the gas exhaust pipe 231a by the turbo molecular pump 246a and the dry pump 246b, for example, N ₂ gas as a pressurizing gas is supplied into the processing chamber 201, Increase pressure. Specifically, the valves 253b and 254 are opened, and N ₂ gas is supplied into the processing chamber 201 through the buffer chamber 237 while controlling the flow rate with the mass flow controller 252b. At this time, the flow rate of the N ₂ gas is set to a predetermined value within a range of, for example, 1000 sccm to 2000 sccm. Accordingly, the pressure in the processing chamber 201 is set to a predetermined value that is, for example, in the range of 100 Pa to 266 Pa and higher than the pressure in the substrate carry-in process. The turbo molecular pump 246a and the dry pump 246b are operated at least until the substrate unloading process described later is completed.

  By maintaining the above state for a predetermined time, for example, 40 seconds to 60 seconds, the temperature of the wafer 200 is gradually raised from the surface on the susceptor 217 side by the radiation of heat from the susceptor 217. At this time, since the wafer 200 is supported away from the susceptor 217, the surface of the wafer 200 on the susceptor 217 side is prevented from being heated rapidly, and the surface of the wafer 200 on the susceptor 217 side (hereinafter referred to as the lower surface). The temperature uniformity of the wafer 200 can be improved by reducing the difference in temperature rising rate between the opposite surface (hereinafter also referred to as the upper surface).

In addition, due to the above, the inside of the processing chamber 201 is filled with N ₂ gas. Thereby, heat is transferred from the susceptor 217 to the wafer 200 by the N ₂ gas existing between the susceptor 217 and the wafer 200. That is, in addition to heat radiation from the susceptor 217, the wafer 200 is also heated by the heat transfer of the N ₂ gas, so that the heating rate of the wafer 200 can be improved.

  The distance between the wafer 200 and the susceptor 217 is preferably adjusted according to the difference between the temperature of the wafer 200 at the time of loading (for example, room temperature) and the temperature of the susceptor 217 heated to a predetermined temperature by the heater 217b. That is, when the difference between the temperature of the wafer 200 and the temperature of the susceptor 217 is large, the distance between the wafer 200 and the susceptor 217 is increased so that the lower surface of the wafer 200 is rapidly heated and the rate of temperature increase with the upper surface is increased. Suppresses the difference. When the difference between the temperature of the wafer 200 and the temperature of the susceptor 217 is small, the temperature of the wafer 200 is accelerated by increasing the distance between the wafer 200 and the susceptor 217 so that the wafer 200 reaches a predetermined temperature. Can be shortened. The distance between the wafer 200 and the susceptor 217 can be adjusted by elevating the susceptor 217 by the susceptor elevating mechanism 268, for example.

The distance between the wafer 200 and the susceptor 217 is not only the temperature difference between the wafer 200 and the susceptor 217 but also the type of gas supplied into the processing chamber 201 (N ₂ gas in this embodiment), the gas flow rate, It is more preferable to adjust according to the pressure in the processing chamber 201 or the like. Thereby, it is possible to suppress the temperature of the lower surface of the wafer 200 from being rapidly increased, or to accelerate the temperature increase of the wafer 200.

(Substrate transfer process)
After a predetermined time has elapsed, the wafer 200 heated to a predetermined temperature is transferred from the wafer push-up pins 266 to the susceptor 217. That is, the susceptor 217 is raised using the susceptor lifting mechanism 268, and the wafer 200 is supported on the upper surface of the susceptor 217. Thereafter, the wafer 200 is raised to a predetermined processing position.

(Processing gas supply process)
Next, N ₂ gas as a processing gas is supplied into the processing chamber 201. In this embodiment, for example, the N ₂ gas used as the pressurizing gas is also used as the processing gas. Therefore, the supply of the N ₂ gas into the processing chamber 201 started in the above-described substrate heating step is continued. N ₂ gas can be supplied. In this state, readjustment is performed by the mass flow controller 252b and the APC 242, and the flow rate of N ₂ gas as the processing gas and the pressure in the processing chamber 201 are set to predetermined values related to the substrate processing. That is, the flow rate of N ₂ gas is set to a predetermined value within a range of, for example, 100 sccm or more and 500 sccm or less. Further, the opening of the APC 242 is adjusted to exhaust the inside of the processing chamber 201 so that the pressure in the processing chamber 201 becomes a predetermined pressure within a range of 1 Pa to 266 Pa, for example. In this manner, while the processing chamber 201 is appropriately evacuated, the supply of N ₂ gas is further continued until the plasma processing step described later is completed.

(Plasma treatment process)
When the pressure in the processing chamber 201 is stabilized, application of high-frequency power having a predetermined output value within a range of, for example, 150 W or more and 1000 W or less is started from the high-frequency power supply 273 to the cylindrical electrode 215 via the matching unit 272. At this time, the impedance variable mechanism 274 is controlled in advance to a predetermined impedance value. As a result, plasma discharge is generated in the processing chamber 201, more specifically, in the plasma generation region 224 above the wafer 200, thereby exciting the N ₂ gas. For example, the N ₂ gas is converted into plasma and dissociated to generate reactive species such as nitrogen active species containing nitrogen (N). Nitridation is performed on the surface of the wafer 200 by the nitrogen active species generated by the excitation of the N ₂ gas.

Thereafter, when a predetermined processing time has elapsed, application of power from the high-frequency power source 273 is stopped, and plasma discharge in the processing chamber 201 is stopped. Further, the valves 253b and 254 are closed to stop the supply of N ₂ gas into the processing chamber 201. Thus, the plasma processing process is completed.

(Exhaust process)
When the supply of N ₂ gas is stopped, the inside of the processing chamber 201 is exhausted using the gas exhaust pipe 231a. Accordingly, and N ₂ gas in the processing chamber 201, N ₂ gas is exhausted to the outside of the processing chamber 201 and the reaction was exhaust gas or the like. Thereafter, the opening degree of the APC 242 is adjusted, and the pressure in the processing chamber 201 is adjusted to the same pressure (for example, 100 Pa) as the substrate transfer chamber adjacent to the processing chamber 201 (unloading destination of the wafer 200, not shown).

(Substrate unloading process)
When the inside of the processing chamber 201 reaches a predetermined pressure, the susceptor 217 is lowered to the transfer position of the wafer 200 and the wafer 200 is supported on the wafer push-up pins 266. Then, the gate valve 244 is opened, and the wafer 200 is carried out of the processing chamber 201 using a transfer mechanism not shown in the drawing. Thus, the substrate processing process according to this embodiment is completed.

When the N ₂ gas is supplied and the pressure in the processing chamber 201 is increased in the substrate temperature raising step, the processing chamber 201 is sealed and the N ₂ gas is sealed in the processing chamber 201. May be. That is, while supplying the N ₂ gas into the processing chamber 201, the APC 242 is closed to stop the exhaust in the processing chamber 201, the N ₂ gas is sealed in the processing chamber 201, and the pressure in the processing chamber 201 is increased. Also good. Thereby, the rate of increase in the pressure in the processing chamber 201 can be increased, and the rate of increase in the temperature of the wafer 200 can be increased. Further, by setting the upper limit of the pressure to 266 Pa so as not to deviate significantly from the pressure during the substrate processing, the pressure adjustment time from the substrate temperature raising step to the plasma processing step can be shortened.

Further, when N ₂ gas or the like is supplied into the processing chamber 201 in the temperature raising step, the supply position of the N ₂ gas or the like can be different from that described above. For example, a nozzle is provided on the side wall of the lower container 211 provided in the processing furnace 203, and the wafer 200 is supported in the vicinity of the transfer position of the wafer 200 when the susceptor 217 is lowered. N ₂ gas or the like is supplied between the 200 and the susceptor 217 through a nozzle. As a result, a part of the N ₂ gas that has received heat from the susceptor 217 on the lower surface side of the wafer 200 goes around to the upper surface side of the wafer 200, and heat transfer to the upper surface side is promoted. Thus, the temperature increase rate of the wafer 200 can be increased also by convection of N ₂ gas or the like.

(3) Effects according to the present embodiment According to the present embodiment, the following one or more effects are achieved.

(A) According to the present embodiment, there is a substrate temperature raising step for raising the temperature of the wafer 200 carried into the processing chamber 201. In other words, in the substrate heating process, the wafer 200 loaded into the processing chamber 201 is moved from the susceptor 217 to the upper side of the susceptor 217 provided in the processing chamber 201 by the wafer push-up pins 266 that temporarily support the wafer 200. The wafer 200 is heated by the heater 217b via the susceptor 217. Thereby, the difference in temperature increase rate between the surface (lower surface) on the susceptor 217 side of the wafer 200 and the surface (upper surface) on the opposite side is reduced, and the temperature uniformity of the wafer 200 can be improved.

(B) According to the present embodiment, in the substrate heating step, the gas supply unit supplies N ₂ gas into the processing chamber 201, and the pressure in the processing chamber 200 is higher than the pressure in the substrate carry-in step. The temperature of the wafer 200 is raised. Thus, in addition to heat radiation from the susceptor 217, heat is transmitted from the susceptor 217 to the wafer 200 by N ₂ gas between the susceptor 217 and the wafer 200, and the temperature increase rate of the wafer 200 is improved, thereby increasing the wafer 200. Can be heated at high speed.

(C) In the present embodiment, the configuration in which the wafer 200 is temporarily supported away from the susceptor 217 changes the timing of a part of the sequence in which the wafer 200 is loaded into the processing chamber 201 and placed at the processing position. Just apply. There is almost no influence on the subsequent plasma treatment process.

(D) Further, according to the present embodiment, the distance between the wafer 200 supported by the wafer push-up pins 266 and the susceptor 217 is set such that the temperature of the wafer 200 at the time of loading and the susceptor 217 heated to a predetermined temperature by the heater 217b. Adjust according to the temperature difference. As a result, when the temperature difference is large, the distance can be increased, and the difference in the heating rate between the lower surface and the upper surface of the wafer 200 can be reduced. Further, when the temperature difference is small, the distance can be made small, and the time required for the temperature rise of the wafer 200 can be further shortened.

(E) Further, according to the present embodiment, the distance between the wafer 200 supported by the wafer push-up pins 266 and the susceptor 217 is determined based on the type of gas supplied into the processing chamber 201 in the heating process, It adjusts according to a flow rate, the pressure in the process chamber 201, etc. As a result, it is possible to suppress a rapid temperature increase on the lower surface of the wafer 200 or to shorten the temperature increase time of the wafer 200.

(F) Also, according to the present embodiment, when N ₂ gas is supplied in the substrate heating step, the wafer 200 supported by the wafer push-up pins 266 is interposed between the susceptor 217 and the nozzle. N ₂ gas or the like is supplied. As a result, the N ₂ gas on the lower surface side of the wafer 200 that has received heat from the susceptor 217 partially enters the upper surface side of the wafer 200 to promote heat transfer, thereby increasing the temperature increase rate of the wafer 200 and increasing the temperature. Time can be shortened.

(G) According to the present embodiment, the temperature uniformity of the wafer 200 can be improved. Therefore, the effect of reducing the warpage of the wafer 200 due to the difference in thermal expansion between the upper and lower surfaces of the wafer 200 can be expected. Such warpage of the wafer 200 is likely to occur when the temperature of the wafer 200 becomes 700 ° C. or more, for example.

<Second Embodiment of the Present Invention>
In the above-described embodiment, the wafer 200 is supported away from the susceptor 217 by the wafer push-up pins 266, and the heat radiation from the susceptor 217 is increased while the processing chamber 201 is filled with N ₂ gas and the pressure is increased. The case where the temperature of the wafer 200 is raised by heat transfer of N ₂ gas has been described. In such a configuration, as the pressure in the processing chamber 201 is increased, the temperature increase rate by heat transfer should be improved. However, in the MMT apparatus 100 according to the above-described embodiment, the upper limit pressure of the diaphragm gauge 241a matched to the pressure region during substrate processing is the upper limit value of the usable pressure.

  Therefore, in the present embodiment, an MMT apparatus capable of performing a substrate processing step in a higher pressure region in order to further reduce the time required for heating the wafer 200 without reducing the measurement accuracy in the substrate processing pressure region. A substrate processing process using the MMT apparatus will be described.

(1) Configuration of Substrate Processing Apparatus The MMT apparatus according to this embodiment differs from the above-described embodiment in the configuration of the gas exhaust unit. Since other configurations are the same as those of the MMT apparatus 100 shown in FIG. 1 described above, description thereof will be omitted, and the configuration of the gas exhaust unit will be described below with reference to FIG. 3A and 3B are diagrams of a gas exhaust unit provided in the MMT apparatus according to the present embodiment, in which FIG. 3A is a schematic diagram illustrating an example of the gas exhaust unit, and FIG. 3B is another example of the gas exhaust unit. It is a schematic diagram shown. In FIG. 3, the same reference numerals are given to the same configurations as the configurations in FIG.

  In the gas exhaust chamber 201a of the gas exhaust section shown in FIG. 3A, a diaphragm gauge 241b as a pressure control sensor such as a capacitance manometer is provided in addition to the diaphragm gauge 241a. The diaphragm gauge 241b is configured to be able to measure up to 10 Torr (1330 Pa) as an upper limit pressure, for example. As a result, by adjusting the valve opening degree of the APC 242 based on the pressure information measured by the diaphragm gauge 241b, the controllable pressure in the processing chamber 201 is the maximum pressure that the turbo molecular pump 246a can handle, for example. The pressure can be increased to about 400 Pa.

  Also in the gas exhaust part of FIG. 3B, a diaphragm gauge 241b is provided in the gas exhaust chamber 201a. Further, the gas exhaust section shown in FIG. 3B has a structure in which the slow exhaust line bypasses the turbo molecular pump 246a. That is, a shutoff valve 243c as an on-off valve is provided between the APC 242 and the turbo molecular pump 246a in the gas exhaust pipe 231a whose upstream end is connected to the gas exhaust chamber 201a. The upstream end of the gas exhaust pipe 231c of the slow exhaust line is connected between the APC 242 of the gas exhaust pipe 231a and the shutoff valve 243c, and between the main valve 243a of the gas exhaust pipe 231a and the dry pump 246b. The downstream end of the gas exhaust pipe 231c is connected. Accordingly, the pressure in the processing chamber 201 can be increased to, for example, about 10 Torr (1330 Pa), which is the upper limit pressure of the diaphragm gauge 241b, regardless of the pressure that can be handled by the turbo molecular pump 246a. That is, with the shut-off valve 243c closed and the slow exhaust valve 243b open, the turbo molecular pump 246a is brought under high pressure by adjusting the valve opening of the APC 242 based on the pressure information measured by the diaphragm gauge 241b. The pressure in the processing chamber 201 can be controlled to a high pressure without exposure. Note that the gas exhaust pipe 231c of the slow exhaust line has an exhaust conductance equivalent to, for example, 3/8 inch piping, and therefore can cope with a high pressure of 400 Pa or more.

(2) Substrate Processing Step The substrate processing step according to the present embodiment is performed, for example, by an MMT apparatus including the gas exhaust unit shown in FIG. 3 as one step of a semiconductor device manufacturing process. Also in the substrate processing step according to the present embodiment, nitriding treatment with N ₂ gas is performed as in the above-described embodiment. However, in the substrate processing step according to the present embodiment, the substrate heating step is mainly described above. Different from the embodiment. Hereinafter, different points will be described. In the following description, it is assumed that the MMT apparatus includes the gas exhaust unit shown in FIG. In addition, the operation of each unit constituting the MMT apparatus according to the present embodiment is controlled by a controller similar to the controller 121 in FIG. 1 described above.

(Substrate heating process)
A temperature raising step is performed on the wafer 200 loaded into the processing chamber 201 in the substrate loading step. That is, in the same procedure as in the above-described embodiment, for example, when the lamp heating unit 280 is used in combination with the heater 217b at 25 ° C. or higher and 700 ° C. or lower, the susceptor 217 is heated to a predetermined temperature within the range of 900 ° C. or lower. Then, the wafer 200 is separated and supported. Further, for example, N ₂ gas as a pressurizing gas is supplied into the processing chamber 201 so that the pressure in the processing chamber 201 is raised, for example, higher than the pressure in the substrate loading process. Specifically, the valves 253b and 254 are opened, and N ₂ gas is supplied into the processing chamber 201 through the buffer chamber 237 while controlling the flow rate with the mass flow controller 252b. At this time, the flow rate of the N ₂ gas is set to a predetermined value within a range of, for example, 1000 sccm to 2000 sccm. In addition, the pressure in the processing chamber 201 is set to a predetermined pressure within a range of, for example, 240 Pa to 1000 Pa, more preferably 400 Pa to 1000 Pa. Specifically, with the shut-off valve 243c closed and the slow exhaust valve 243b opened, the opening of the APC 242 is adjusted based on pressure information measured by the diaphragm gauge 241b, and the inside of the processing chamber 201 is exhausted.

Thereby, the inside of the processing chamber 201 is filled with N ₂ gas. By maintaining this state for a predetermined time, for example, 40 seconds to 60 seconds, heat is transferred from the susceptor 217 to the wafer 200 by the N ₂ gas existing between the susceptor 217 and the wafer 200. That is, in addition to heat radiation from the susceptor 217, the wafer 200 is also heated by the heat transfer of the N ₂ gas, so that the heating rate of the wafer 200 can be improved.

Further, the distance between the wafer 200 supported by the wafer push-up pins 266 and the susceptor 217, the temperature difference between the wafer 200 and the susceptor 217, and the type of gas supplied into the processing chamber 201 (N _{2 in} this embodiment). Gas), the flow rate of the gas, the pressure in the processing chamber 201, and the like. Thereby, it is possible to suppress the temperature of the lower surface of the wafer 200 from being rapidly increased, or to accelerate the temperature increase of the wafer 200.

(Substrate transfer process)
After the predetermined time has elapsed, the wafer 200 is transferred to the susceptor 217 and raised to a predetermined processing position by the same procedure as the substrate transfer process according to the above-described embodiment.

(Processing gas supply process)
In the present embodiment, for example, the supply of N ₂ gas into the processing chamber 201 started in the above-described substrate heating step is continued. In this state, readjustment by the mass flow controller 252b and the APC 242 is performed, and the flow rate of the N ₂ gas as the processing gas and the pressure in the processing chamber 201 are, for example, predetermined values similar to the processing gas supply process according to the above-described embodiment. And

At this time, the pressure control by the APC 242 is performed based on pressure information measured by the diaphragm gauge 241a. Thereby, the pressure at the time of substrate processing performed under a pressure of, for example, 266 Pa or less, more preferably 240 Pa or less can be accurately controlled. Thus, by properly using the diaphragm gauges 241a and 241b according to the control pressure in each process, the pressure in the processing chamber 201 can be accurately measured and controlled.

  In order to set the pressure in the processing chamber 201 to a predetermined value, the shut-off valve 243c is closed so that the turbo molecular pump 246a is not exposed to high pressure until the pressure in the processing chamber 201 drops to about 400 Pa, for example. While the exhaust valve 243b is opened, the exhaust of the processing chamber 201 is continued through the slow exhaust line. After the pressure in the processing chamber 201 becomes 400 Pa or less, the slow exhaust valve 243b is closed, the shut-off valve 243c is opened, and the processing chamber 201 is exhausted through the turbo molecular pump 246a.

  This is the end of the description of the substrate processing process performed by the MMT apparatus including the gas exhaust unit shown in FIG.

Note that the method using the nozzle provided on the side wall of the lower container 211 for supplying N ₂ gas or the like in the substrate heating step described in the above embodiment, or N ₂ gas is enclosed in the processing chamber 201. A technique for increasing the pressure in the processing chamber 201 can also be applied to this embodiment. When N ₂ gas is sealed, the upper limit pressure can be increased to 1000 Pa in the present embodiment.

  Further, when the MMT apparatus includes the gas exhaust unit of FIG. 3A, the pressure in the processing chamber 201 in the temperature raising step is set to, for example, 1 Pa or more and 400 Pa or less with the upper limit of the pressure that can be supported by the turbo molecular pump 246a. be able to.

(3) Effects according to the present embodiment The present embodiment has the same effects as the above-described embodiment.

(A) Moreover, according to this embodiment, the pressure in the processing chamber 200 is increased to 240 Pa or more and 1000 Pa or less, more preferably 400 Pa or more and 1000 Pa or less in the substrate heating step. Thereby, the transfer of heat from the susceptor 217 to the wafer 200 by the N ₂ gas is further promoted, the temperature increase rate of the wafer 200 can be further improved, and the temperature increase time can be shortened.

(B) Further, according to the present embodiment, the gas exhaust part includes the diaphragm gauge 241a whose upper limit of the measurement pressure is 2 Torr (266 Pa) and the diaphragm gauge 241b whose upper limit of the measurement pressure is 10 Torr (1330 Pa). Yes. Further, in the processing gas supply process, the plasma processing process, etc., the pressure in the processing chamber 201 is controlled based on the pressure information of the diaphragm gauge 241a, and in the substrate temperature raising process, the pressure control in the processing chamber 201 is performed based on the pressure information of the diaphragm gauge 241b. I do. Thereby, the pressure in the processing chamber 201 can be further increased in the substrate heating step while maintaining the accuracy of the control pressure during the substrate processing.

(C) Moreover, according to this embodiment, the gas exhaust part is provided with the slow exhaust line of the structure which bypasses the turbo-molecular pump 246a. Thereby, in the temperature raising step, the pressure in the processing chamber 201 can be increased to the upper limit pressure of the diaphragm gauge 241b, which is higher than the pressure that can be handled by the turbo molecular pump 246a. Therefore, the temperature of the wafer 200 can be increased even faster.

<Third embodiment of the present invention>
In the above-described embodiment, the case where the temperature of the wafer 200 is increased by using the heater 217b embedded in the susceptor 217 as a heating unit has been described. However, with such a technique, the temperature of the wafer 200 is mainly increased by heating from the lower surface side of the wafer 200, and there may be a case where the difference in the temperature increase rate between the lower surface and the upper surface of the wafer 200 is not sufficiently reduced.

Further, as in the above-described embodiment, when N ₂ gas or the like is blown from the shower head 236 above the wafer 200 and supplied into the processing chamber 201, for example, the supplied N ₂ gas or the like has a relatively low temperature. In this case, it is conceivable that N ₂ gas or the like directly hits the upper surface of the wafer 200 to cool the upper surface of the wafer 200, and the effect of reducing the difference in temperature increase rate with the lower surface of the wafer 200 is weakened.

  Accordingly, the present inventors have further studied to further increase the effect of reducing the difference in temperature increase rate between the lower surface and the upper surface of the wafer 200. Hereinafter, based on the knowledge obtained by the present inventors from such research results, a technique for further reducing the temperature increase rate difference between the lower surface and the upper surface of the wafer 200 and further improving the temperature uniformity of the wafer 200 will be described.

(1) Substrate Processing Step Also in the substrate processing step according to the present embodiment, nitriding processing with N ₂ gas is performed using the MMT apparatus provided with the gas exhaust section shown in FIG. Hereinafter, the substrate heating process different from the above-described embodiment will be mainly described.

(Substrate heating process)
Above the susceptor 217 heated to a predetermined temperature within the range of 900 ° C. or lower when the lamp heating unit 280 is used in combination with the lamp heating unit 280 by the procedure similar to the above-described embodiment, for example, by the heater 217b, The wafer 200 is separated and supported. Further, the valves 253a and 254 are opened, and the flow rate is controlled by the mass flow controller 252a, and the wafer 200 or a gas inert to the process applied to the wafer 200, for example, N ₂ , is entered into the processing chamber 201 via the buffer chamber 237. An inert gas such as a gas, helium (He) gas, argon (Ar) gas, krypton (Kr) gas, or xenon (Xe) gas is supplied. Here, for example, when N ₂ gas is used, the flow rate of N ₂ gas can be set to a predetermined value within a range of 1000 sccm to 2000 sccm, for example. In addition, the pressure in the processing chamber 201 is set to a predetermined pressure within a range of, for example, 240 Pa to 1000 Pa, more preferably 400 Pa to 1000 Pa.

  Next, when the pressure in the processing chamber 201 is stabilized, high-frequency power having a predetermined output value within a range of 150 W or more and 1000 W or less is applied to the cylindrical electrode 215 from the high-frequency power supply 273 via the matching unit 272, for example. Start. At this time, the impedance variable mechanism 274 is controlled in advance to a predetermined impedance value. This causes plasma discharge in the processing chamber 201, more specifically, in the plasma generation region 224 above the wafer 200.

  In this manner, the inert gas is excited to generate plasma above the wafer 200, whereby heat from the plasma is transmitted to the wafer 200, and the wafer 200 is also heated from the upper surface side. Accordingly, the temperature of the wafer 200 can be increased by heating the wafer 200 from both sides using the heater 217b on the lower surface side of the wafer 200 and the plasma on the upper surface side of the wafer 200 as heat sources. Therefore, the difference in the heating rate between the lower surface and the upper surface of the wafer 200 can be further reduced.

  Further, when the high frequency power is applied, the temperature of the wafer 200 rapidly increases. For this reason, the temperature raising time of the wafer 200 can be further shortened as compared with the case where the gas is supplied without being converted into plasma as in the above-described embodiment.

In addition, the wafer 200 is exposed to, for example, the atmosphere before being loaded into the processing chamber 201, and a natural oxide film (SiO ₂ film) may be formed on the surface of the wafer 200 in advance. In such a case, H ₂ gas may be introduced into the processing chamber 201 and excited. For example, the H ₂ gas is turned into plasma and dissociated to generate reactive species such as hydrogen active species containing hydrogen (H). With the generated hydrogen active species or the like, the natural oxide film on the surface of the wafer 200 can be etched to remove at least a part thereof. The etching rate of the natural oxide film by H ₂ gas plasma increases as the temperature of the wafer 200 is higher, that is, as the temperature of the heater 217b is set higher in advance. The etching rate is also increased by increasing the high frequency power applied to the cylindrical electrode 215. Thus, by removing the natural oxide film on the surface of the wafer 200 in advance, the nitriding rate and nitriding concentration in the plasma processing step can be improved.

In addition, an uneven pattern may be formed on the surface of the wafer 200, and a natural oxide film (SiO ₂ ) may be formed on substantially the entire surface. In such a case, a vacuum capacitance is formed between the wafer 200 and the impedance adjustment electrode 217c by increasing the protrusion height of the protrusion pin 266. The vacuum capacitance reduces the bias of the wafer 200 to reduce the amount of plasma drawn, suppresses the removal rate of the bottom surface of the concave portion and the top surface of the convex portion with respect to the side surface of the concave and convex pattern, and the bottom surface and top surface of the concave and convex pattern. The natural oxide film formed at the same time can be removed uniformly. Therefore, even when a concavo-convex pattern is formed on the surface of the wafer 200, the influence of the natural oxide film can be reduced, and the nitriding rate and nitriding concentration in the plasma processing step can be improved.

After elapse of a predetermined time, for example, 40 seconds to 60 seconds, plasma discharge in the processing chamber 201 is stopped and supply of H ₂ gas is stopped. The plasma discharge may be stopped after the application of the high-frequency power when any of the above-described effects such as reduction of the temperature increase rate difference or shortening of the temperature increase time is obtained. It is not necessary to maintain the plasma discharge.

  As described above, in the present embodiment, the plasma generation unit also functions as a heating unit.

(Substrate transfer process)
After the predetermined time has elapsed, the wafer 200 is transferred to the susceptor 217 and raised to a predetermined processing position by the same procedure as the substrate transfer process according to the above-described embodiment. Moreover, and _{H 2} gas in the process chamber 201, the _{H 2} gas is exhausted to the outside of the processing chamber 201 and the reaction was exhaust gas or the like. This makes it possible to H ₂ gas or the like to suppress the influence on the process after remaining in the processing chamber 201.

  The description of the substrate processing step according to the present embodiment that is different from the above-described embodiment is completed.

  In addition to the above-described technique using plasma, a method of heating the wafer 200 from the upper surface side of the wafer 200 to reduce the difference in the heating rate between the lower surface and the upper surface of the wafer 200 can be considered. For example, a gas heated to a predetermined temperature is ejected from the shower head 236 above the wafer 200 and supplied into the processing chamber 201. Thereby, the wafer 200 can be heated from the upper surface side. According to this method, the inside of the processing chamber 201 is filled with the gas at a predetermined temperature, so that the periphery of the wafer 200 becomes a substantially constant temperature, and heat radiation from the outer peripheral portion of the wafer 200 can be suppressed. Thereby, the difference of the temperature increase rate in the surface of the wafer 200 can also be reduced. Therefore, the temperature uniformity of the wafer 200 can be further improved. Thus, in such a configuration, the gas supply unit also functions as a heating unit.

  Further, by using the lamp heating unit 280 as the lamp heating apparatus described so far, the wafer 200 is heated from above the wafer 200, and the temperature rising rate between the lower surface and the upper surface of the wafer 200 is increased. There is an effect of reducing the difference. Thus, from such a viewpoint, it can be said that the lamp heating unit 280 also functions as a heating unit.

(2) Effects according to the present embodiment The same effects as those of the above-described embodiment are also achieved in the present embodiment.

(A) Further, according to the present embodiment, when the temperature of the wafer 200 supported by the wafer push-up pins 266 is raised in the substrate temperature raising step, the inert gas is supplied into the processing chamber 201 by the gas supply unit. An inert gas is excited by the plasma generation unit to generate plasma above the wafer 200. Accordingly, the temperature of the wafer 200 can be increased by heating the wafer 200 using the heater 217b on the lower surface side of the wafer 200 and the plasma on the upper surface side of the wafer 200 as heat sources. Therefore, the difference in the heating rate between the lower surface and the upper surface of the wafer 200 can be further reduced, and the temperature uniformity of the wafer 200 can be further improved.

(B) According to the present embodiment, the inert gas is turned into plasma by applying high-frequency power in the substrate heating step. Thereby, when the high frequency power is applied, the temperature of the wafer 200 can be rapidly increased. Therefore, it is possible to raise the temperature of the wafer 200 at a higher speed than when the gas is supplied without being converted into plasma.

(C) Further, according to the present embodiment, in the substrate heating step, the H ₂ gas is excited and turned into plasma. Thereby, the natural oxide film formed on the surface of the wafer 200 can be removed, and the nitriding speed and nitriding density in the plasma processing step can be improved.

FIG. 4B shows measured values of the natural oxide film thickness after the APM cleaning and the H ₂ gas plasma treatment of the sample manufactured by the flow shown in FIG. In the process using H ₂ gas plasma, the temperature of the heater 217b is set to 600 ° C. (indicated by a □ in the figure) in a state where the wafer 200 is directly placed on the susceptor 217 in order to control the temperature of the wafer 200 and increase the experimental accuracy. No.) and 900 ° C. (in the figure, marks ●). As shown in FIG. 4B, the natural oxide film can be removed by increasing the temperature of the heater 217b and performing the treatment with H ₂ gas plasma.

In the present embodiment, since the nitriding process is performed subsequent to the process using the H ₂ gas plasma in the same processing chamber 201, the wafer 200 is not exposed to the air on the way, and the nitriding process is further improved in efficiency. Is done.

(D) Further, according to the present embodiment, the H ₂ gas is excited to become plasma while the wafer 200 is separated from the susceptor 217 and supported by the wafer push-up pins 266. As a result, the distance between the wafer 200 and the impedance adjustment electrode 217c is increased, and a vacuum impedance is formed, so that the bias can be weakened. That is, the force for drawing the active species in the plasma into the wafer 200 can be weakened. Therefore, even when a concavo-convex pattern is formed on the wafer 200 and a natural oxide film is formed on the surface of the concavo-convex pattern, the natural oxide film formed on the bottom and top surfaces and the side surfaces of the concavo-convex pattern is uniform. Can be removed.

(E) According to the present embodiment, not only the temperature of the wafer 200 is raised but also a secondary process such as natural oxide film removal is performed in the temperature raising step. Thereby, the efficiency of the substrate processing step can be improved, and the productivity of the substrate processing can be improved.

(F) Further, according to the present embodiment, the wafer 200 is heated from above by the heated gas or the lamp heating unit 280. Thereby, the difference in the temperature increase rate between the upper surface and the lower surface of the wafer 200 is further reduced.

(G) In addition, when a heated gas is used, heat from the outer periphery of the wafer 200 is suppressed by filling the periphery of the wafer 200 with a gas at a predetermined temperature, and the difference in the temperature increase rate within the surface of the wafer 200 is suppressed. The temperature uniformity of the wafer 200 is further improved.

<Other Embodiments of the Present Invention>
As mentioned above, although embodiment of this invention was described concretely, this invention is not limited to the above-mentioned embodiment, It can change variously in the range which does not deviate from the summary.

  For example, in the above-described embodiment, the susceptor 217 is raised to move the wafer 200 supported by the wafer push-up pins 266 onto the susceptor 217. For example, the wafer push-up pins are moved up and down. A driving mechanism may be provided and the wafer 200 may be transferred onto the susceptor by lowering the wafer push-up pins. In the above-described embodiment, the susceptor 217 is lowered when the wafer 200 is supported on the wafer push-up pins 266. However, the wafer 200 is placed on the wafer push-up pins by raising the wafer push-up pins. It may be supported. As a result, it is possible to simplify the mechanism of the raising / lowering operation rather than the raising / lowering operation of the susceptor 217, and to reduce the power consumption of the substrate processing apparatus. In addition, a drive mechanism for moving up and down or the like may be provided in each of the susceptor and the wafer push-up pin so that both the susceptor and the wafer push-up pin move up and down, and each may move up and down relatively.

  In the above-described embodiment, the wafer 200 is supported by the wafer push-up pins 266 so as to be separated from the susceptor 217. However, the support of the wafer 200 is not limited to that by the wafer push-up pins 266. The wafer 200 may be supported by being hung from the susceptor by being separated from the susceptor by suspending the wafer 200 from the susceptor by stopping the carrier 200 for carrying the wafer 200 into the processing chamber 201 for a predetermined time. Good. Further, for example, the upper surface of the susceptor may be subjected to uneven processing (embossing), and the wafer 200 may be supported by the convex portions on the upper surface of the susceptor. Thereby, the contact area between the susceptor and the wafer 200 is reduced, and the side slip of the wafer 200 when the wafer 200 is placed can be suppressed. Further, scratches and the like formed on the back surface of the wafer 200 can be reduced. Further, the warpage of the wafer 200 can be reduced.

  Further, as described above, the heater 217b provided in the susceptor 217, the lamp heating unit 280, the plasma generation unit, the gas supply unit that supplies the heated gas, and the like can be used as the heating unit. At that time, the heating unit may be any one of the heater 217b, the lamp heating unit 280, the plasma generation unit, the gas supply unit, or some or all of them. In any of the above combinations, the wafer 200 is supported away from the susceptor 217 in the substrate heating step, and the distance between the susceptor 217 and the wafer 200 is appropriately adjusted, so that the temperature environment of the upper and lower surfaces of the wafer 200 can be adjusted. It can be made uniform. Therefore, a difference in temperature increase rate between the upper and lower surfaces hardly occurs, and the temperature uniformity of the wafer 200 can be improved.

Further, the gas to be supplied into the processing chamber 201 in the temperature raising step to increase the pressure or the gas to be converted into plasma is not limited to the N ₂ gas or the H ₂ gas shown in the above embodiment, but the contents of the substrate processing and the wafer 200 Depending on the surface condition (presence or absence of formation of a predetermined film, etc.), it can be appropriately selected. Some specific examples are shown below.

For example, when nitriding the Si surface of the wafer 200 or a silicon oxide film (SiO ₂ film), a rare gas such as Ar gas, He gas, or Kr gas can be used in addition to the N ₂ gas and H ₂ gas described above. . However, O ₂ gas is not preferable because it may remain in the processing chamber 201 and reduce the nitriding efficiency.

Further, for example, N ₂ gas, O ₂ gas, H ₂ gas, rare gas, or the like can be used at the time of oxidation treatment of Si or the like. However, when forming a gate oxide film of a semiconductor device such as a flash memory, it is not preferable to use H ₂ gas that is taken into the gate oxide film and may deteriorate the electrical characteristics.

In addition, for example, N ₂ gas or rare gas can be used during the annealing process. However, a gas that may oxidize or reduce the wafer 200 or a film formed on the wafer 200 at a high temperature during the annealing process, such as O ₂ gas or H ₂ gas, is not preferable.

In addition, N ₂ gas, O ₂ gas, H ₂ gas, rare gas, or the like can be used at the time of selective oxidation performed on a laminated structure such as a SiO ₂ film / metal film (in no particular order), and CVD (Chemical Vapor Deposition). N ₂ gas, rare gas, or the like can be used at the time of various film formations using the method.

  In any process, heat transfer efficiency can be further improved by using a gas having a small molecular weight or molecular size, such as He gas.

  Further, the present invention can be applied not only to the substrate processing described above but also to processing such as oxynitriding, diffusion, etching, annealing, etc., in which oxidation and nitriding are performed together on a bare wafer or a wafer on which various films are formed. It is. The above treatment can be performed with plasma or without plasma.

<Preferred embodiment of the present invention>
Hereinafter, preferred embodiments of the present invention will be additionally described.

One embodiment of the present invention provides:
A processing chamber for processing the substrate;
A first substrate support part for temporarily supporting the substrate carried into the processing chamber;
A second substrate support unit provided in the processing chamber and to which the substrate is transferred from the first substrate support unit;
A heating section for heating the substrate carried into the processing chamber;
Above the second substrate support unit, the substrate carried into the processing chamber is supported by the first substrate support unit away from the second substrate support unit, and the substrate is heated by the heating unit,
After a predetermined time has elapsed, the substrate is transferred from the first substrate support part to the second substrate support part,
A substrate processing apparatus comprising: the first substrate support unit and a control unit that controls the heating unit so that the substrate is processed while the substrate is heated by the heating unit.

Preferably,
The distance between the substrate supported by the first substrate support unit and the second substrate support unit is the temperature of the substrate at the time of loading and the temperature of the second substrate support unit heated to a predetermined temperature by the heating unit. It is configured to be adjusted according to the difference.

Preferably,
A gas supply unit for supplying gas into the processing chamber;
The controller is
When raising the temperature of the substrate supported by the first substrate support unit, the gas is supplied into the processing chamber by the gas supply unit so that the pressure in the processing chamber is higher than the pressure at the time of loading the substrate. Further, the gas supply unit is controlled.

Preferably,
The heating unit is
A plasma generation unit for exciting the gas supplied into the processing chamber;
The controller is
The plasma generation unit is further configured to excite the gas by the plasma generation unit when the temperature of the substrate supplied by the gas supply unit into the processing chamber and supported by the first substrate support unit is increased. To control.

More preferably,
A natural oxide film is formed on the surface of the substrate,
The gas is a hydrogen-containing gas.

Preferably,
The heating unit is
A lamp heating device provided above the first substrate support;
The controller is
When the temperature of the substrate supported by the first substrate support portion is raised, the lamp heating device is further controlled so that the lamp heating device heats the substrate from above.

Another aspect of the present invention is:
Carrying the substrate into a processing chamber for processing the substrate;
The first substrate support unit that temporarily supports the substrate is supported above the second substrate support unit provided in the processing chamber and separated from the second substrate support unit above the second substrate support unit. And heating the substrate by a heating unit that heats the substrate carried into the processing chamber;
Transferring the substrate from the first substrate support to the second substrate support after a predetermined time has elapsed;
Processing the substrate while heating the substrate by the heating unit;
And a step of unloading the substrate from the processing chamber.

Preferably,
The distance between the substrate supported by the first substrate support unit and the second substrate support unit is the temperature of the substrate at the time of loading and the temperature of the second substrate support unit heated to a predetermined temperature by the heating unit. Adjust according to the difference.

Preferably,
In the step of raising the temperature of the substrate supported by the first substrate support part,
Gas is supplied into the processing chamber by the gas supply unit, and the pressure in the processing chamber is increased from the pressure in the step of loading the substrate.

Preferably,
In the step of raising the temperature of the substrate supported by the first substrate support part,
A gas is supplied into the processing chamber by a gas supply unit, and the gas is excited by a plasma generation unit included in the heating unit.

More preferably,
A natural oxide film is formed on the surface of the substrate,
The gas is a hydrogen-containing gas.

Preferably,
In the step of raising the temperature of the substrate supported by the first substrate support part,
The substrate is heated from above by a lamp heating device provided in the heating unit and provided above the first substrate support unit.

121 Controller (control unit)
200 wafer (substrate)
201 processing chamber 217 susceptor (second substrate support)
217b Heater (heating unit)
266 Wafer push-up pin (first substrate support)

Claims (7)

A processing chamber for processing the substrate;
A first substrate support part for temporarily supporting the substrate carried into the processing chamber;
A second substrate support unit provided in the processing chamber and to which the substrate is transferred from the first substrate support unit;
A heating unit configured to include at least a lamp heating device provided above the first substrate support and a heater provided inside the second substrate support, and heating the substrate carried into the processing chamber;
A gas supply unit for supplying gas into the processing chamber;
An exhaust part for exhausting the processing chamber,
Supporting the substrate carried into the processing chamber away from the second substrate support unit by the first substrate support unit above the second substrate support unit;
Setting the pressure in the processing chamber to a predetermined pressure higher than the pressure at the time of loading the substrate, and raising the temperature of the substrate supported by the first substrate support unit by the heating unit;
Transferring the substrate from the first substrate support to the second substrate support after a predetermined time has elapsed;
Supplying a processing gas from the gas supply unit, and processing the substrate while heating the substrate supported by the second substrate support unit by the heating unit;
A control unit configured to control at least one of the first substrate support unit or the second substrate support unit, the heating unit, the gas supply unit, and the exhaust unit,
A substrate processing apparatus further comprising:   The distance between the substrate supported by the first substrate support unit and the second substrate support unit is the temperature of the substrate at the time of loading and the temperature of the second substrate support unit heated to a predetermined temperature by the heating unit. The substrate processing apparatus according to claim 1, wherein the substrate processing apparatus is configured to be adjusted according to a difference between the two. A plasma generation unit for plasma-exciting the gas in the processing chamber;
The controller is
The substrate processing apparatus according to claim 1, wherein, in the step of processing the substrate, the plasma generation unit is controlled so that the processing gas supplied into the processing chamber is plasma-excited. Carrying the substrate into a processing chamber for processing the substrate;
The first substrate support unit that temporarily supports the substrate is supported above the second substrate support unit provided in the processing chamber and separated from the second substrate support unit above the second substrate support unit. And a process of
A lamp heating apparatus in which the pressure in the processing chamber is set to a predetermined pressure higher than the pressure at the time of loading the substrate, and the substrate supported by the first substrate support is provided at least above the first substrate support. And a step of raising the temperature by a heating part constituted by a heater provided inside the second substrate support part,
Transferring the substrate from the first substrate support to the second substrate support after a predetermined time has elapsed;
Supplying a processing gas into the processing chamber and processing the substrate while heating the substrate supported by the second substrate support unit by the heating unit;
Unloading the substrate from the processing chamber;
A method for manufacturing a semiconductor device comprising: The distance between the substrate supported by the first substrate support unit and the second substrate support unit is the temperature of the substrate at the time of loading and the temperature of the second substrate support unit heated to a predetermined temperature by the heating unit. The method of manufacturing a semiconductor device according to claim 4 , wherein the semiconductor device is adjusted according to a difference between In the step of raising the temperature of the substrate supported by the first substrate support part,
Manufacturing method of the process by supplying a hydrogen-containing gas into the chamber, the semiconductor device according to the hydrogen-containing gas in the processing chamber to claim 4 or claim 5 for plasma excitation. Carrying the substrate into a processing chamber for processing the substrate;
The first substrate support unit that temporarily supports the substrate is supported above the second substrate support unit provided in the processing chamber and separated from the second substrate support unit above the second substrate support unit. And a process of
A lamp heating apparatus in which the pressure in the processing chamber is set to a predetermined pressure higher than the pressure at the time of loading the substrate, and the substrate supported by the first substrate support is provided at least above the first substrate support. And a step of raising the temperature by a heating part constituted by a heater provided inside the second substrate support part,
Transferring the substrate from the first substrate support to the second substrate support after a predetermined time has elapsed;
Supplying a processing gas into the processing chamber and processing the substrate while heating the substrate supported by the second substrate support unit by the heating unit;
Unloading the substrate from the processing chamber.

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