JP2004281853A - Substrate processing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate processing system for forming a desired film on a substrate by alternately supplying a reaction chamber for housing the substrate with a first reaction gas and a second reaction gas by which an efficient film formation can be performed in a short sequence time. <P>SOLUTION: A processing furnace 202 is alternately supplied with dichlorosilane (DCS) and NH<SB>3</SB>for forming a SiN film. In this case, purging after supply of DCS is conducted by using NH<SB>3</SB>which is not plasma activated. In this way, after supplying DCS, there is no need for a purging with N<SB>2</SB>gas or an evacuation, the sequence time becomes short and an efficient film formation can be performed. Also, before discharge in the NH<SB>3</SB>gas, the NH<SB>3</SB>gas is made to flow and a buffer chamber 237 as a discharge region is subjected to substitution with NH<SB>3</SB>gas. Then a discharge is induced. In this way, all the discharging time can be used to supply the desired excited species such as radicals or the like. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a substrate processing apparatus, and more particularly, to a film forming apparatus used in manufacturing a semiconductor device such as Si.
[0002]
[Prior art]
A conventional semiconductor device manufacturing apparatus for performing film formation by an ALD (Atomic layer Deposition) method includes a first process gas supply, a N ₂ Purging, evacuation, followed by supply of a second process gas, N 2 ₂ Purging and evacuation are performed, and these sequences are repeated.
[0003]
However, there is a problem that simply repeating these steps increases the time of each step.
[0004]
Further, when the supply of the process gas is insufficient, the uniformity of the film thickness becomes uneven, and when the purge is insufficient, there is a problem that particles are generated. For this purpose, it is necessary to sufficiently supply the process gas and to sufficiently purge the gas.
As a result, there is a disadvantage that the total sequence time becomes long.
[0005]
[Problems to be solved by the invention]
The present invention provides a method of forming a desired film on a substrate by alternately supplying a first reaction gas and a second reaction gas into a reaction chamber containing the substrate, such as an ALD method. A main object of the present invention is to provide a substrate processing apparatus for processing, which has a short sequence time and can perform efficient film formation.
[0006]
[Means for Solving the Problems]
According to the present invention,
A substrate processing apparatus for alternately supplying a first reaction gas and a second reaction gas into a reaction chamber containing a substrate, and forming a desired film on the substrate,
Stopping the supply of the first reaction gas into the reaction chamber and then supplying the second reaction gas into the reaction chamber, thereby discharging the first reaction gas; Reacting the reaction gas with the first reaction gas adsorbed on the substrate to form a film on the substrate.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
In a preferred embodiment of the present invention, there is provided a semiconductor device manufacturing apparatus in which a first process gas and a second process gas are alternately supplied into a reaction chamber and a film is formed on a substrate in the reaction chamber by an ALD method. , After the first process gas flows, ₂ The purging of the reaction chamber is performed by using the gas, but the purging of the reaction chamber is performed by using the second process gas.
[0008]
By doing so, the N 2 gas after the first process gas flows ₂ There is no need to purge or evacuate the reaction chamber with a gas, so that the sequence time is shortened and efficient film formation can be performed.
[0009]
This method can be suitably applied when the second process gas is used by being excited by plasma discharge or the like.
[0010]
Specifically, for example, dichlorosilane (DCS) and plasma-excited NH ₃ When forming a SiN film by using DCS, purging after supplying DCS is performed using NH that is not subjected to plasma excitation. ₃ Purge using.
[0011]
In a preferred embodiment of the present invention, the first process gas and the second process gas excited by the plasma discharge are alternately supplied into the reaction chamber to form a film on the substrate in the reaction chamber by the ALD method. In the semiconductor device manufacturing apparatus, when the second process gas is caused to flow in the discharge region where the plasma discharge is performed, the second process gas is caused to flow in the discharge region prior to performing the plasma discharge to prepare for the discharge. .
[0012]
When a process gas for performing a plasma discharge is supplied, if the process gas is supplied before the timing for performing the discharge, the discharge region is replaced with the process gas, and the entire discharge time is excited by desired radicals or the like. Useful for seed supply. This is particularly effective when evacuation time, which is a step before flowing the second process gas, is short, or when evacuation is not performed before flowing the second process gas.
[0013]
Specifically, for example, dichlorosilane (DCS) and plasma-excited NH ₃ When forming a SiN film using ₃ 1 to 4 sec before the discharge of ₃ It is good to start flowing.
[0014]
In addition, the above-mentioned purge, that is, NH that is not subjected to plasma excitation after DCS is supplied. ₃ Can be performed at the same time as the purging performed, thereby increasing the effectiveness.
[0015]
In a preferred embodiment of the present invention, a semiconductor device manufacturing method in which a first process gas and a second process gas are alternately supplied into a reaction chamber and a film is formed on a substrate in the reaction chamber by an ALD method. In the apparatus, when the first process gas flows from the first nozzle, the second process gas flows from the second nozzle to N ₂ Flow. Further, when the second process gas flows from the second nozzle, N flows from the first nozzle through which the first process gas flows. ₂ Is more preferable.
[0016]
This can prevent one gas from entering the nozzle of the other gas, thereby shortening the purge time. In particular, when the nozzle shape is complicated, the effect is more remarkably exhibited. In the next step, N ₂ When purging, N ₂ Supply can be performed quickly.
[0017]
Specifically, dichlorosilane (DCS) and NH ₃ In the step of supplying DCS when forming a SiN film using ₃ From the nozzle of N ₂ And NH ₃ Is supplied from the DCS nozzle to N ₂ So that it is flowing.
[0018]
In a preferred embodiment of the present invention, a semiconductor device manufacturing method in which a first process gas and a second process gas are alternately supplied into a reaction chamber and a film is formed on a substrate in the reaction chamber by an ALD method. In the apparatus, when the first process gas flows from the first nozzle, N flows from the second nozzle through which the second process gas flows. ₂ After that, when the second process gas flows from the second nozzle, N gas is continuously supplied from the second nozzle. ₂ To make it flow. More preferably, when the second process gas flows from the second nozzle, the first process gas flows from the first nozzle to N ₂ Then, when the first process gas flows from the first nozzle, N gas is continuously supplied from the first nozzle. ₂ To make it flow.
[0019]
In this way, in the next step N ₂ When purging, N ₂ Supply can be performed quickly. When supplying the process gas, ₂ By reducing the flow rate, the influence on the supply of the process gas can be reduced.
[0020]
Specifically, dichlorosilane (DCS) and NH ₃ DCS supply and N ₂ After purging and evacuating, NH 3 ₃ When supplying NH ₃ N from nozzle ₂ Keep flowing.
[0021]
In a preferred embodiment of the present invention, a semiconductor device manufacturing method in which a first process gas and a second process gas are alternately supplied into a reaction chamber and a film is formed on a substrate in the reaction chamber by an ALD method. In the apparatus, when the first process gas flows from the first nozzle, N flows from the second nozzle through which the second process gas flows. ₂ And from the second nozzle in a subsequent purge step ₂ Try to reduce the flow rate. More preferably, when the second process gas flows from the second nozzle, N flows from the first nozzle through which the first process gas flows. ₂ In the following purge step, N is supplied from the first nozzle. ₂ Try to reduce the flow rate.
[0022]
In this way, when one gas is supplied, a large flow rate of N ₂ Is flowing in the next purge step ₂ By lowering the flow rate of the process gas, it is possible to quickly switch to the other process gas.
[0023]
Specifically, dichlorosilane (DCS) and NH ₃ Is used to form a SiN film, and when DCS is supplied, NH ₃ Large amount of N from the nozzle ₂ Of DCS, N of DCS ₂ In the purge step, NH ₃ N from nozzle ₂ By reducing the flow rate, NH ₃ Replacement is faster.
[0024]
In a preferred embodiment of the present invention, a semiconductor device manufacturing method in which a first process gas and a second process gas are alternately supplied into a reaction chamber and a film is formed on a substrate in the reaction chamber by an ALD method. In the device,
After the first or second process gas is introduced into the reaction chamber, it is stored in the reaction chamber for a while. As a result, the diffusion of the process gas can be advanced, and the process gas can be adsorbed on the entire wafer.
[0025]
Specifically, dichlorosilane (DCS) and NH ₃ When forming a SiN film and supplying DCS by closing the exhaust valve so that gas is stored in the reaction chamber, uniformity of the film thickness can be improved.
[0026]
Next, a film forming process using an ALD method, which is one of the CVD methods, will be described as an example of a process process on a substrate such as a wafer, which is a preferred embodiment of the present invention, with reference to the drawings.
[0027]
According to the ALD method, two kinds (or more) of raw material gases to be used for film formation are alternately supplied one by one to a substrate under a certain film formation condition (temperature, time, etc.), and one atomic layer unit is used. This is a method of forming a film by utilizing a surface reaction.
[0028]
That is, for example, in the case of forming a SiN (silicon nitride) film, DCS (SiH ₂ Cl ₂ , Dichlorosilane) and NH ₃ High-quality film formation is possible at a low temperature of 300 to 600 ° C. using (ammonia). The gas supply alternately supplies a plurality of types of reactive gases one by one. Then, the film thickness is controlled by the number of cycles of the reactive gas supply (for example, when the film forming speed is 1 ° / cycle, when forming a 20 ° film, 20 cycles of processing are performed).
[0029]
FIG. 1 is a schematic configuration diagram of a vertical type substrate processing furnace according to a preferred embodiment of the present invention. FIG. 2 shows a vertical section of the processing furnace portion, and FIG. 2 shows a vertical type substrate processing furnace according to a preferred embodiment of the present invention. It is a schematic structure figure of a substrate processing furnace, and shows a processing furnace part in a cross section. A reaction tube 203 is provided inside the heater 207 as a heating means as a reaction container for processing the wafer 200 as a substrate, and the lower end opening of the reaction tube 203 is sealed with an O-ring as an airtight member by a seal cap 219 as a lid. The processing furnace 202 is formed by at least the heater 207, the reaction tube 203, and the seal cap 219. A boat 217 as a substrate holding means is erected on the seal cap 219 via a quartz cap 218, and the quartz cap 218 serves as a holding body for holding the boat. Then, the boat 217 is inserted into the processing furnace 202. A plurality of wafers 200 to be batch-processed are loaded on the boat 217 in a horizontal posture in multiple stages in the tube axis direction. The heater 207 heats the wafer 200 inserted into the processing furnace 202 to a predetermined temperature.
[0030]
The processing furnace 202 is provided with two gas supply pipes 232a and 232b as supply pipes for supplying a plurality of kinds, here two kinds of gases. Here, the reaction gas is supplied from the gas supply pipe 232a to the processing furnace 202 via a mass flow controller 241a as a flow rate control means and a valve 243a as an opening / closing valve, and further through a buffer chamber 237 formed in the processing furnace 202 described later. The reaction gas is supplied from the gas supply pipe 232b to the processing furnace 202 via a mass flow controller 241b as a flow rate control means, a valve 243b as an open / close valve, and further via a gas supply unit 249 described later.
[0031]
The processing furnace 202 is connected to a vacuum pump 246 as an exhaust means via a valve 243d by a gas exhaust pipe 231 which is an exhaust pipe for exhausting gas, and is evacuated. The valve 243d is an opening / closing valve that can open and close the valve to evacuate and stop the evacuation of the processing furnace 202, and can further adjust the valve opening to adjust the pressure.
[0032]
In the arc-shaped space between the inner wall of the reaction tube 203 and the wafer 200 constituting the processing furnace 202, a gas dispersion space is formed on the inner wall above the lower part of the reaction tube 203 along the loading direction of the wafer 200. A buffer chamber 237 is provided, and a gas supply hole 248a, which is a supply hole for supplying gas, is provided at an end of a wall of the buffer chamber 237 adjacent to the wafer 200. The gas supply hole 248a opens toward the center of the reaction tube 203. The gas supply holes 248a have the same opening area from the lower part to the upper part, and are provided at the same opening pitch.
[0033]
A nozzle 233 is arranged at the end of the buffer chamber 237 opposite to the end where the gas supply hole 248 a is provided, also along the loading direction of the wafer 200 from above the lower part of the reaction tube 203 to the upper part. . The nozzle 233 is provided with a gas supply hole 248b which is a supply hole for supplying a plurality of gases. When the pressure difference between the buffer chamber 237 and the processing furnace 202 is small, the opening area of the gas supply holes 248b may have the same opening area and the same opening pitch from the upstream side to the downstream side, but the pressure difference is large. In this case, the opening area may be increased from the upstream side to the downstream side, or the opening pitch may be reduced.
[0034]
By adjusting the opening area and the opening pitch of the gas supply holes 248b from the upstream side to the downstream side, first, a gas having a difference in the gas flow velocity from each gas supply hole 248b, but the flow rate is substantially the same is ejected. Then, the gas ejected from each of the gas supply holes 248b is ejected into the buffer chamber 237 and once introduced therein, and the flow velocity difference of the gas is made uniform.
[0035]
That is, in the buffer chamber 237, the gas ejected from each gas supply hole 248b is ejected from the gas supply hole 248a to the processing furnace 202 after the particle velocity of each gas is reduced in the buffer chamber 237. During this time, when the gas ejected from each gas supply hole 248b was ejected from each gas supply hole 248a, it could be a gas having a uniform flow rate and flow rate.
[0036]
Further, in the buffer chamber 237, a bar-shaped electrode 269 and a bar-shaped electrode 270 having an elongated structure are disposed and protected by an electrode protection tube 275, which is a protection tube for protecting the electrodes from the upper portion to the lower portion. One of the terminals 270 is connected to a high-frequency power supply 273 via a matching unit 272, and the other is connected to a ground which is a reference potential. As a result, plasma is generated in the plasma generation region 224 between the rod-shaped electrode 269 and the rod-shaped electrode 270.
[0037]
The electrode protection tube 275 has a structure in which each of the rod-shaped electrode 269 and the rod-shaped electrode 270 can be inserted into the buffer chamber 237 in a state where it is isolated from the atmosphere of the buffer chamber 237. Here, if the inside of the electrode protection tube 275 has the same atmosphere as the outside air (atmosphere), the rod-shaped electrode 269 and the rod-shaped electrode 270 inserted into the electrode protection tube 275 are oxidized by the heating of the heater 207. Therefore, the inside of the electrode protection tube 275 is filled or purged with an inert gas such as nitrogen, and an inert gas purge mechanism is provided for keeping the oxygen concentration sufficiently low to prevent the rod-shaped electrode 269 or the rod-shaped electrode 270 from being oxidized.
[0038]
Further, a gas supply unit 249 is provided on an inner wall which is about 120 ° around the inner circumference of the reaction tube 203 from the position of the gas supply hole 248a. The gas supply unit 249 is a supply unit that shares the buffer chamber 237 and the gas supply type when alternately supplying a plurality of types of gases to the wafer 200 one by one in film formation by the ALD method.
[0039]
The gas supply section 249 also has a gas supply hole 248c which is a supply hole for supplying gas at the same pitch at a position adjacent to the wafer at a position adjacent to the wafer similarly to the buffer chamber 237, and a gas supply pipe 232b is connected at a lower portion.
[0040]
When the differential pressure between the buffer chamber 237 and the processing furnace 202 is small, the opening area of the gas supply holes 248c may have the same opening area and the same opening pitch from the upstream side to the downstream side. It is preferable to increase the opening area or decrease the opening pitch from the upstream side to the downstream side.
[0041]
A boat 217 on which a plurality of wafers 200 are mounted at the same interval in multiple stages is provided at a central portion in the reaction tube 203. The boat 217 can be moved into and out of the reaction tube 203 by a boat elevator mechanism not shown in the drawing. It has become. Further, a boat rotating mechanism 267 as a rotating means for rotating the boat 217 is provided to improve the uniformity of the processing, and the boat 217 held by the quartz cap 218 is rotated by rotating the boat rotating mechanism 267. It is designed to rotate.
[0042]
The controller 321 serving as a control means is connected to the mass flow controllers 241a and 241b, the valves 243a, 243b and 243d, the heater 207, the vacuum pump 246, the boat rotating mechanism 267, the boat elevating mechanism not shown in the drawing, the high frequency power supply 273, and the matching device 272. The flow rates of the mass flow controllers 241a and 241b, the opening and closing operations of the valves 243a and 243b, the opening and closing and pressure adjusting operations of the valve 243d, the temperature control of the heater 207, the start and stop of the vacuum pump 246, the rotation speed of the boat rotation mechanism 267 The adjustment, the raising / lowering operation control of the boat lifting / lowering mechanism, the power supply control of the high-frequency electrode 273, and the impedance control by the matching unit 272 are performed.
[0043]
(First Embodiment)
Next, DCS and NH will be described for an example of film formation by the ALD method. ₃ An example in which a SiN film is formed using a gas will be described.
[0044]
First, the wafer 200 on which a film is to be formed is loaded into the boat 217 and is loaded into the processing furnace 202. After carrying in, evacuating, and waiting for the temperature to rise, the next step is sequentially executed.
[0045]
[Step 1]
In step 1, NH required for plasma excitation ₃ Let the gas flow. First, the valve 243a provided on the gas supply pipe 232a and the valve 243d provided on the gas exhaust pipe 231 are both opened, and the NH flow rate adjusted by the mass flow controller 241a from the gas supply pipe 232a. ₃ Gas is blown out from the gas supply hole 248b of the nozzle 233 to the buffer chamber 237, and is blown out to the processing furnace 202 from the gas supply hole 248a. Thereafter, high-frequency power is applied between the rod-shaped electrode 269 and the rod-shaped electrode 270 from the high-frequency power supply 273 via the matching device 272 to thereby obtain NH3. ₃ Is plasma-excited and exhausted from the gas exhaust pipe 231 while being supplied to the processing furnace 202 as active species. NH ₃ When the gas is excited as plasma to flow as active species, the pressure in the processing furnace 202 is adjusted to 10 to 100 Pa by appropriately adjusting the valve 243d. NH controlled by mass flow controller 241a ₃ Is 1000 to 10000 sccm. NH ₃ The time for exposing the wafer 200 to the active species obtained by exciting the plasma is 2 to 120 seconds. The temperature of the heater 207 at this time is set so that the temperature of the wafer becomes 300 to 600 ° C. NH ₃ Since the reaction temperature is high, it does not react at the above-mentioned wafer temperature, so that it is made to flow as active species by exciting the plasma, so that the wafer temperature can be kept in a set low temperature range. At this time, the gas flowing into the processing furnace 202 is NH 3 ₃ Is an active species obtained by plasma excitation, and DCS does not exist. Therefore, NH ₃ Does not cause a gas phase reaction, and is excited by plasma to become active species. ₃ Reacts with the underlying film on the wafer 200.
[0046]
[Step 2]
In step 2, the valve 243a of the gas supply pipe 232a is closed and NH 3 ₃ Stop supplying. Further, the processing furnace 202 is evacuated to 20 Pa or less by the vacuum pump 246 while the valve 243d of the gas exhaust pipe 231 is kept open, and the residual NH ₃ From the processing furnace 202. At this time, N ₂ Is supplied to the processing furnace 202, the residual NH ₃ The effect of eliminating is increased.
[0047]
[Step 3]
In step 3, DCS gas that does not require plasma excitation is flowed. That is, the residual NH ₃ Is removed from the processing furnace 202, the valve 243d of the gas exhaust pipe 231 is kept open, the valve 243b provided on the gas supply pipe 232b is opened, and the DCS whose flow rate is adjusted by the mass flow controller 241b from the gas supply pipe 232b. The gas is supplied to the gas supply unit 249 and exhausted from the gas exhaust pipe 231 while being supplied to the processing furnace 202 from the gas supply hole 248c. When flowing the DCS gas, the pressure in the processing furnace 202 is adjusted to 700 to 3500 Pa by appropriately adjusting the valve 243d. The supply flow rate of DCS controlled by the mass flow controller 241b is 500 to 2000 sccm. The time for exposing the wafer 200 to DCS gas is 1 to 20 seconds. The temperature of the heater 207 at this time is NH ₃ Is set so that the temperature of the wafer is 300 to 600 ° C. as in the case of the supply.
[0048]
By supplying DCS, NH on the underlying film is reduced. ₃ And DCS undergo a surface reaction to form a SiN film on the wafer 200.
[0049]
[Step 4]
After the film formation, the valve 243b is closed, the supply of DCS gas is stopped, the valve 243a is opened, and the NH flow rate adjusted by the mass flow controller 241a from the gas supply pipe 232a. ₃ Gas is blown out from the gas supply hole 248b of the nozzle 233 to the buffer chamber 237, and is blown out to the processing furnace 202 from the gas supply hole 248a. Processing furnace 202 ₃ Purge with gas to remove residual DCS from processing furnace 202.
[0050]
[Step 5]
The residual DCS is removed from the processing furnace 202 by NH. ₃ After purging with a gas, high frequency power is applied between the rod-shaped electrode 269 and the rod-shaped electrode 270 from the high-frequency power source 273 via the matching device 272 to obtain NH3. ₃ Is plasma-excited and exhausted from the gas exhaust pipe 231 while being supplied to the processing furnace 202 as active species. NH ₃ When the gas is excited as plasma to flow as active species, the pressure in the processing furnace 202 is adjusted to 10 to 100 Pa by appropriately adjusting the valve 243d. NH controlled by mass flow controller 241a ₃ Is 1000 to 10000 sccm. NH ₃ The time for exposing the wafer 200 to the active species obtained by exciting the plasma is 2 to 120 seconds. The temperature of the heater 207 at this time is set so that the temperature of the wafer becomes 300 to 600 ° C. NH excited by plasma to become active species ₃ Reacts with the SiN film on the wafer 200.
[0051]
Steps 3 to 5 are defined as one cycle, and this cycle is repeated a plurality of times to form a SiN film having a predetermined thickness on the wafer.
[0052]
In the present embodiment, the purge after the supply of DCS is performed by NH that is not subjected to plasma excitation. ₃ Therefore, N after supplying DCS ₂ There is no need to perform gas purging or vacuum evacuation, so that the sequence time is shortened and efficient film formation can be performed.
[0053]
Also, NH ₃ Prior to the gas discharge timing, NH 3 ₃ Since the gas is flowing, the buffer chamber 237, which is a discharge area, is filled with NH. ₃ After the gas is replaced, the discharge is performed, and the entire discharge time can be used for supplying excited species such as desired radicals.
[0054]
The processing furnace 202 is evacuated and NH ₃ Since DCS is flowed after removing the gas, both do not react on the way to the wafer 200. The supplied DCS is the NHs adsorbed on the wafer 200. ₃ And can only react effectively.
[0055]
(Second embodiment)
In the present embodiment, in the step of supplying DCS, NHS is supplied. ₃ N from supply nozzle ₂ And NH ₃ Is supplied from the DCS supply nozzle. ₂ So that it is flowing.
[0056]
That is, while the valve 243d of the gas exhaust pipe 231 is open, the valve 243b provided on the gas supply pipe 232b is opened, and the DCS gas whose flow rate is adjusted by the mass flow controller 241b is supplied from the gas supply pipe 232b to the gas supply unit 249. Then, the gas is exhausted from the gas exhaust pipe 231 while being supplied to the processing furnace 202 from the gas supply hole 248c. At this time, the valve 243a is opened, and the flow rate is adjusted from the gas supply pipe 232a by the mass flow controller 241a. ₂ Gas is blown out from the gas supply hole 248b of the nozzle 233 to the buffer chamber 237, and N is supplied from the gas supply hole 248a. ₂ Gas is injected into the processing furnace 202.
[0057]
Further, with the valve 243d of the gas exhaust pipe 231 opened, the valve 243a is opened, and the NH flow rate adjusted by the mass flow controller 241a from the gas supply pipe 232a. ₃ Gas is blown out from the gas supply hole 248 b of the nozzle 233 into the buffer chamber 237. The high frequency power is applied between the rod-shaped electrode 269 and the rod-shaped electrode 270 from the high-frequency power source 273 through the matching unit 272, and NH ₃ Is plasma-excited and exhausted from the gas exhaust pipe 231 while being supplied as active species to the processing furnace 202 through the gas supply holes 248a. At this time, the valve 243b provided on the gas supply pipe 232b is opened, and the flow rate of the N controlled by the mass flow controller 241b from the gas supply pipe 232b. ₂ The gas is supplied to the gas supply unit 249, and N is supplied from the gas supply hole 248c. ₂ Gas is injected into the processing furnace 202.
[0058]
This can prevent one gas from entering the nozzle of the other gas, thereby shortening the purge time. In particular, when the nozzle shape is complicated, the effect is more remarkably exhibited. In the next step, N ₂ When purging, N ₂ Supply can be performed quickly.
[0059]
(Third embodiment)
In this embodiment mode, dichlorosilane (DCS) and NH ₃ DCS supply and N ₂ After purging and evacuating, NH 3 ₃ When supplying NH ₃ N from nozzle ₂ Keep flowing.
[0060]
That is, the valve 243d of the gas exhaust pipe 231 is kept open, the valve 243b provided in the gas supply pipe 232b is opened, and the DCS gas whose flow rate has been adjusted by the mass flow controller 241b from the gas supply pipe 232b is supplied to the gas supply unit 249. And exhausted from the gas exhaust pipe 231 while supplying the gas to the processing furnace 202 through the gas supply hole 248c. At this time, the valve 243a is opened, and the flow rate is adjusted from the gas supply pipe 232a by the mass flow controller 241a. ₂ Gas is blown out from the gas supply hole 248b of the nozzle 233 to the buffer chamber 237, and N is supplied from the gas supply hole 248a. ₂ Gas is injected into the processing furnace 202.
[0061]
Thereafter, the valve 243b of the gas supply pipe 232b is closed to stop the supply of the DCS gas. Further, the processing furnace 202 is evacuated by the vacuum pump 246 with the valve 243 d of the gas exhaust pipe 231 kept open, and the residual DCS is removed from the processing furnace 202. At this time, the valve 243a is kept open, and the flow rate of the N controlled by the mass flow controller 241a is controlled from the gas supply pipe 232a. ₂ Gas is blown out from the gas supply hole 248b of the nozzle 233 to the buffer chamber 237, and N is supplied from the gas supply hole 248a. ₂ The gas is blown into the processing furnace 202.
[0062]
After that, the valve 243d of the gas exhaust pipe 231 is opened, the valve 243a is kept open, and the gas supply pipe 232a is ₂ In a state where the gas is supplied, NH whose flow rate is adjusted from the gas supply pipe 232a by the mass flow controller 241a is adjusted. ₃ Gas is blown out from the gas supply hole 248 b of the nozzle 233 into the buffer chamber 237. A high frequency power is applied between the rod-shaped electrode 269 and the rod-shaped electrode 270 from the high-frequency power source 273 via the matching unit 272, and NH is applied. ₃ Is exhausted from the gas exhaust pipe 231 while being supplied to the processing furnace 202 through the gas supply holes 248a as active species. At this time, NH is supplied from the gas supply pipe 232a. ₃ N as well as gas ₂ Gas is also supplied and NH ₃ When gas is supplied to the processing furnace 202 from the gas supply holes 248a, N ₂ Gas is also supplied to the processing furnace 202 through the gas supply holes 248a.
[0063]
In this way, in the next step N ₂ When purging, N ₂ Supply can be performed quickly. When supplying the process gas, ₂ By reducing the flow rate, the influence on the supply of the process gas can be reduced.
[0064]
(Fourth embodiment)
In this embodiment mode, dichlorosilane (DCS) and NH ₃ Is used to form a SiN film, and when DCS is supplied, NH ₃ Large amount of N from the nozzle ₂ Of DCS, N of DCS ₂ In the purge step, NH ₃ N from nozzle ₂ By reducing the flow rate, NH ₃ Faster replacement with
[0065]
That is, the valve 243d of the gas exhaust pipe 231 is kept open, the valve 243b provided in the gas supply pipe 232b is opened, and the DCS gas whose flow rate has been adjusted by the mass flow controller 241b from the gas supply pipe 232b is supplied to the gas supply unit 249. And exhausted from the gas exhaust pipe 231 while supplying the gas to the processing furnace 202 through the gas supply hole 248c. At this time, the valve 243a is opened, and the flow rate is adjusted from the gas supply pipe 232a by the mass flow controller 241a. ₂ A large amount of gas is ejected from the gas supply hole 248b of the nozzle 233 to the buffer chamber 237, and N is supplied from the gas supply hole 248a. ₂ A large amount of gas is injected into the processing furnace 202.
[0066]
Thereafter, the valve 243b of the gas supply pipe 232b is closed to stop the supply of the DCS gas. The valve 243d of the gas exhaust pipe 231 is kept open. And N instead of DCS gas ₂ The gas is supplied to the mass flow controller 241b, the valve 243b is opened, and N is supplied from the gas supply hole 248c to the processing furnace 202. ₂ The gas is exhausted from the gas exhaust pipe 231 while supplying gas, and N of DCS is exhausted. ₂ Perform a purge. At this time, the valve 243a is kept open, and the mass flow controller 241a keeps the N flowing through the gas supply pipe 232a. ₂ Reduce gas flow.
[0067]
After that, while the valve 243d of the gas exhaust pipe 231 is open, N gas is supplied to the gas supply pipe 232a. ₂ NH in addition to gas ₃ Supply gas, NH ₃ Gas and N ₂ Gas is ejected from the gas supply hole 248 b of the nozzle 233 into the buffer chamber 237. A high frequency power is applied between the rod-shaped electrode 269 and the rod-shaped electrode 270 from the high-frequency power source 273 via the matching unit 272, and NH is applied. ₃ Is exhausted from the gas exhaust pipe 231 while being supplied to the processing furnace 202 through the gas supply holes 248a as active species. At this time, NH is supplied from the gas supply hole 248a. ₃ N as well as gas ₂ The gas is also supplied to the processing furnace 202 together.
[0068]
In this way, when one gas is supplied, a large flow rate of N ₂ Is flowing in the next purge step ₂ By lowering the flow rate of the process gas, it is possible to quickly switch to the other process gas.
[0069]
(Fifth embodiment)
In the present embodiment, dichlorosilane (DCS) and NH ₃ When DCS is supplied when forming a SiN film by using the method described above, the valve 243d of the gas exhaust pipe 231 is closed, and the DCS gas is stored in the processing furnace 202. Can be. As a result, the diffusion of the process gas can be advanced, and the process gas can be adsorbed on the entire wafer.
[0070]
Next, an outline of a semiconductor manufacturing apparatus which is an example of a substrate processing apparatus to which the present invention is suitably applied will be described with reference to FIGS.
On the front side inside the housing 101, a cassette stage 105 is provided as a holder transferring member for transferring the cassette 100 as a substrate storage container to and from an external transfer device (not shown). Is provided with a cassette elevator 115 as elevating means, and a cassette transfer machine 114 as transport means is attached to the cassette elevator 115. On the rear side of the cassette elevator 115, a cassette shelf 109 as a mounting means for the cassette 100 is provided, and a spare cassette shelf 110 is also provided above the cassette stage 105. A clean unit 118 is provided above the spare cassette shelf 110 so that clean air can flow through the inside of the housing 101.
[0071]
A processing furnace 202 is provided above the rear part of the housing 101, and a boat 217 as substrate holding means for holding wafers 200 as substrates in multiple stages in a horizontal position is moved up and down the processing furnace 202 below the processing furnace 202. A boat elevator 121 is provided as elevating means, and a seal cap 219 as a lid is attached to a tip end of an elevating member 122 attached to the boat elevator 121 to support the boat 217 vertically. A transfer elevator 113 as an elevating means is provided between the boat elevator 121 and the cassette shelf 109, and a wafer transfer machine 112 as a transfer means is attached to the transfer elevator 113. Further, a furnace port shutter 116 as a shielding member having an opening / closing mechanism and closing the lower surface of the processing furnace 202 is provided beside the boat elevator 121.
[0072]
The cassette 100 loaded with the wafers 200 is loaded into the cassette stage 105 from an external transfer device (not shown) in an upward posture, and is rotated by 90 ° on the cassette stage 105 so that the wafers 200 are in a horizontal posture. Further, the cassette 100 is conveyed from the cassette stage 105 to the cassette shelf 109 or the spare cassette shelf 110 by the cooperation of the elevating operation, the traversing operation, and the reciprocating operation and the rotating operation of the cassette elevator 115.
[0073]
The cassette shelf 109 has a transfer shelf 123 in which the cassette 100 to be transferred by the wafer transfer device 112 is stored. The cassette 100 on which the wafer 200 is transferred is controlled by a cassette elevator 115 and a cassette transfer device 114. It is transferred to the transfer shelf 123.
[0074]
When the cassette 100 is transferred to the transfer shelf 123, the wafers 200 are transferred from the transfer shelf 123 to the boat 217 in a lowered state by the cooperation of the forward / backward operation, the rotation operation, and the elevating operation of the transfer elevator 113. Transfer.
[0075]
When a predetermined number of wafers 200 are transferred to the boat 217, the boat 217 is inserted into the processing furnace 202 by the boat elevator 121, and the processing furnace 202 is hermetically closed by the seal cap 219. The wafer 200 is heated in the hermetically closed processing furnace 202, and a processing gas is supplied into the processing furnace 202 to process the wafer 200.
[0076]
When the processing on the wafer 200 is completed, the wafer 200 is transferred from the boat 217 to the cassette 100 on the transfer shelf 123 by the reverse procedure of the above-described operation, and the cassette 100 is transferred from the transfer shelf 123 by the cassette transfer machine 114. It is transferred to the cassette stage 105 and carried out of the housing 101 by an external transfer device (not shown). The furnace port shutter 116 closes the lower surface of the processing furnace 202 when the boat 217 is in the lowered state, thereby preventing outside air from being caught in the processing furnace 202.
The transfer operation of the cassette transfer device 114 and the like is controlled by the transfer control means 124.
[0077]
【The invention's effect】
According to the present invention, a first reaction gas and a second reaction gas are alternately supplied into a reaction chamber accommodating a substrate, such as an ALD method, to form a desired film on the substrate. And a substrate processing apparatus for performing efficient film formation in which the sequence time is short.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a vertical substrate processing furnace according to an embodiment of the present invention, and is a diagram illustrating a processing furnace portion in a vertical cross section.
FIG. 2 is a schematic configuration diagram of a vertical type substrate processing furnace according to an embodiment of the present invention, and is a diagram showing a processing furnace portion in a cross section.
FIG. 3 is a schematic perspective view showing a vertical substrate processing apparatus according to an embodiment of the present invention.
FIG. 4 is a schematic vertical sectional view showing a vertical substrate processing apparatus according to an embodiment of the present invention.
[Explanation of symbols]
100 ... cassette
101 ... housing
105: Cassette stage
109 ... cassette shelf
110 ... spare cassette shelf
112 ... Wafer transfer machine
113 ... Transfer elevator
114 ... Cassette transfer machine
115 ... Cassette elevator
116: Furnace shutter
118 ... Clean unit
121 ... Boat elevator
122 ... elevating member
123 ... Transfer shelf
124: transport control means
200 ... wafer
202: Processing furnace
203 ... reaction tube
207 ... heater
217 ... Boat
218 ... Quartz cap
219… Seal cap
220 ... O-ring
224: Plasma generation area
231 ... gas exhaust pipe
232a, 232b ... gas supply pipe
233 ... Nozzle
237 ... Buffer room
241a, 241b ... mass flow controller
243a, 243b, 243d ... valves
246 ... Vacuum pump
248a, 248b, 248c ... gas supply holes
249 ... Gas supply unit
267 ... Boat rotation mechanism
269, 270 ... rod-shaped electrode
271… Earth
272 ... matching device
273 ... High frequency power supply
275 ... Electrode protection tube
321 ... controller

Claims (1)

A substrate processing apparatus for alternately supplying a first reaction gas and a second reaction gas into a reaction chamber containing a substrate, and forming a desired film on the substrate,
Stopping the supply of the first reaction gas into the reaction chamber and then supplying the second reaction gas into the reaction chamber, thereby discharging the first reaction gas; Reacting the reaction gas with the first reaction gas adsorbed on the substrate to form a film on the substrate.

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