JP2004006801A - Vertical semiconductor manufacturing equipment - Google Patents

Abstract

In a vertical semiconductor manufacturing apparatus for forming a film by alternately flowing different gases, the throughput can be improved even if the furnace volume is large.
A vertical semiconductor manufacturing apparatus supplies a reaction furnace, an exhaust pipe connected to a vacuum pump, a first supply pipe for supplying a first gas contributing to film formation, and a second gas. A second supply pipe 38, valves 22 to 25 for controlling supply of the first and second supply pipes and exhaust of the exhaust pipe 40, a gas reservoir 21 provided in the first supply pipe 41, and a control unit 29. The control means controls the valves 22 to 25 to flow the first gas through the first supply pipe 41 and store the first gas in the gas reservoir 21, and the first gas stored in the gas reservoir 21 with the exhaust of the furnace 20 stopped. By supplying the gas to the furnace 20, the pressure of the furnace 20 is increased and the substrate W is exposed to the first gas. The substrate is exposed to the second gas by supplying the second gas to the furnace 20 through the second supply pipe 38 while exhausting the furnace 20 by the pump 26.
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a vertical semiconductor manufacturing apparatus, and more particularly to a vertical semiconductor manufacturing apparatus in which a plurality of types of gases contributing to film formation are alternately flowed to form a film on a laminated substrate.
[0002]
[Prior art]
FIG. 7 shows an atomic layer deposition apparatus (hereinafter, simply referred to as an ALD (Atomic Layer Deposition) apparatus) which is a conventional example of a semiconductor device manufacturing apparatus which performs film formation by alternately flowing a plurality of types of gases contributing to film formation. Show. This is, for example, a method in which two kinds of process gases a and b contributing to film formation are exhausted while being alternately supplied into the reaction chamber 1 and adsorbed and reacted on a substrate in the reaction chamber 1 to form a film. It is. In this case, the gas supply amounts of the process gases a and b are controlled by mass flow controllers (MFCs) 2 and 3 provided in the gas supply pipes 7 and 8, respectively. The pressure in the reaction chamber 1 is controlled by controlling the amount of exhaust by adjusting the opening of an exhaust valve 6 provided in an exhaust pipe 9.
[0003]
[Problems to be solved by the invention]
However, in the above-described conventional ALD apparatus, particularly when the process gas is supplied to the reaction chamber, the gas pressure can be increased in a short time because the process gas is supplied while controlling the exhaust amount from the reaction chamber. However, there is a drawback that the adsorption and reaction speeds are reduced due to the delay of the gas pressure rise. This disadvantage does not cause much problem in a single-wafer type ALD apparatus for simultaneously processing about 1 to 2 substrates because the volume of the reaction chamber is small, but in particular, a batch type ALD apparatus for simultaneously processing a large number of stacked substrates. In the vertical type ALD apparatus, since the volume of the reaction chamber is large, there is a problem that the adsorption and the delay of the reaction rate become remarkable, and the throughput is largely reduced.
[0004]
As a conventional technique, there is a single-wafer type film forming apparatus that continuously supplies oxygen (O) radicals in a reaction chamber and supplies TEOS gas intermittently for about 2 seconds to form an aggregated film. . In this apparatus, gas reservoirs 303 and 304 are provided in a gas supply system supplied from the TEOS cylinder to the reaction chamber, and the TEOS gas stored in the gas reservoir is supplied to the reaction chamber. Further, by providing two gas reservoirs, it becomes possible to store gas in one gas reservoir while using the other gas reservoir, thereby improving the throughput. However, the apparatus provided with the gas reservoir is for a single-wafer apparatus having a small reaction chamber volume, and is not for a vertical apparatus having a large reaction chamber volume. Further, this is not an ALD apparatus for alternately supplying the process gases a and b into the reaction chamber.
[0005]
A main object of the present invention is to provide a vertical type semiconductor manufacturing apparatus in which a plurality of types of gases contributing to film formation are alternately flowed, which can solve the above-described problems of the prior art and can improve the throughput. An object of the present invention is to provide a semiconductor manufacturing apparatus.
[0006]
[Means for Solving the Problems]
According to the present invention, a vertical reaction chamber for accommodating a plurality of stacked substrates, an exhaust path for exhausting the reaction chamber, and a vacuum exhaust unit for exhausting the reaction chamber via the exhaust path. An exhaust valve that opens and closes the exhaust path, a first supply path that supplies a first type of gas that contributes to film formation to the reaction chamber, and a second type of gas that contributes to the film formation. A second supply path for supplying the gas to the reaction chamber; a gas supply valve for opening and closing the first and second supply paths; and an exhaust valve and the gas supply valve. When supplying, the first type of gas is supplied to the reaction chamber from the first supply path in a state where the exhaust of the reaction chamber is stopped. When the second type of gas is supplied to the reaction chamber, By supplying the gas of the second type to the reaction chamber through the second supply path while exhausting the reaction chamber by an exhaust unit, the plurality of substrates in the reaction chamber can be exhausted by the second type of gas. A vertical semiconductor manufacturing apparatus provided with a control means for exposing to a gas is provided.
[0007]
According to the vertical semiconductor manufacturing apparatus of the present invention, the first type of gas is supplied to the reaction chamber in a state where the exhaust is stopped, so that the pressure in the reaction chamber is increased. Therefore, as compared with the case where the reaction chamber is pressurized while controlling the exhaust gas amount, even in a vertical ALD apparatus having a large reaction chamber volume, the reaction chamber can be pressurized in a short time, and a high pressurized state can be achieved. Can be easily obtained. The shorter the pressure raising time and the higher the pressure to be raised, the higher the rate of adsorption to the substrate and the film formation rate, and the higher the throughput.
[0008]
Preferably, the second kind of gas is activated and supplied by plasma excitation.
Also, preferably, the second type of gas is ammonia. In this case, preferably, the pressure of the reaction chamber when the ammonia gas is supplied is set to 10 to 100 Pa. More preferably, the pressure in the reaction chamber when the ammonia gas is supplied is 30 to 60 Pa.
It is preferable that the first type gas is supplied without being activated by plasma excitation.
Preferably, the first type of gas is dichlorosilane.
[0009]
Preferably, the first supply path has a gas reservoir for storing the first type of gas, and the control unit controls the first type of gas when supplying the first type of gas to the reaction chamber. The first type of gas is stored in the gas reservoir by flowing the first type of gas through the first supply path, and the first type of gas stored in the gas reservoir is removed from the gas reservoir while the exhaust of the reaction chamber is stopped. To expose the plurality of substrates in the reaction chamber to the first type of gas.
[0010]
According to this configuration, the first type of gas is stored in the gas reservoir, and the first type of gas stored in the gas reservoir is supplied to the reaction chamber in a state where the exhaust is stopped. I do. Therefore, as compared with the case where the reaction chamber is pressurized while controlling the exhaust gas amount, even in a vertical ALD apparatus having a large reaction chamber volume, the reaction chamber can be pressurized instantaneously, and the high pressure state can be obtained. Can be obtained more easily. It is possible to further increase the rate of adsorption to the substrate and the film formation, and to greatly improve the throughput.
[0011]
Preferably, the pressure of the gas reservoir is 20,000 Pa or more.
Preferably, the volume of the gas reservoir is set to 1/1000 to 3/1000 of the volume of the reaction chamber.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described.
[0013]
6A and 6B show a basic configuration diagram of a vertical ALD device according to the embodiment, wherein FIG. 6A is a schematic diagram showing a vertical cross section, and FIG. 6B is a schematic diagram showing a horizontal cross section. Inside the heater 31, a reaction tube 32 constituting a reaction chamber for processing a substrate is provided. The lower end opening of the reaction tube 32 is hermetically closed by a seal cap 35, and a boat 39 is erected on the seal cap 35 and inserted into the reaction tube 32. On the boat 39, a plurality of substrates W to be batch-processed are stacked in multiple stages in the tube axis direction in a horizontal posture. The heater 31 heats the substrate W in the reaction tube 32 to a predetermined temperature.
[0014]
Two gas supply pipes are provided in the reaction tube 32 as supply paths for supplying a plurality of types, here two types of gases. Here, the first gas supply pipe 41 does not pass through the remote plasma unit, and the second gas supply pipe 38 is connected to one side of the reaction tube 32 via the remote plasma unit 37. Therefore, there are two types of gas supplied to the plurality of substrates W in the reaction tube 32: a gas supplied without being excited by plasma and a gas supplied as active species by being excited by plasma. An exhaust pipe 40 is provided on the other side of the reaction tube 32 as an exhaust path for exhausting the reaction chamber. The exhaust pipe 40 is connected to a vacuum pump as a vacuum exhaust unit (not shown).
[0015]
The remote plasma unit 37 is connected to the nozzle 30 erected along the boat 39 in the reaction tube 32. The nozzle 30 is provided with a large number of outlet holes 34 along the nozzle axis direction so as to face a large number of substrates stacked in multiple stages.
[0016]
The outlet hole 34 reduces the outlet hole diameter of the gas upstream and the outlet hole diameter of the gas downstream in order to uniformly supply the excited gas or the non-excited gas from the substrate W upstream of the gas to the substrate W downstream of the gas. By changing the conductance, the conductance is changed so that the gas is blown out evenly upstream and downstream.
[0017]
Further, control means for controlling the flow of two kinds of gases and the film formation temperature of the substrate W are provided. The control means includes a gas supply control means 43 for controlling two kinds of gases to flow alternately one by one, and a temperature control means 42 for controlling a film forming temperature by heater heating.
[0018]
Next, a method for forming a film using the above-described vertical ALD apparatus having the basic configuration will be described. The film is Si ₃ N ₄ Form a film. The reaction gas is DCS (SiH ₂ Cl ₂ : Dichlorosilane) and plasma-treated NH ₃ It is.
[0019]
First, a substrate W on which a film is to be formed is loaded into a boat 39 and carried into a reaction tube 32 (hereinafter, also simply referred to as a furnace). Next, Si on the substrate ₃ N ₄ A film is formed. The furnace temperature at this time is a temperature at which a film having good adhesion to the base film and having few defects at the interface is formed, for example, 350 to 600 ° C. For this film formation, NH 3 ₃ And DCS are alternately flowed to form an atomic layer by ALD.
[0020]
First, NH is supplied from the second gas supply pipe 38. ₃ Supply. NH ₃ Does not react at the above furnace temperature because the reaction temperature is higher than DCS. Therefore, NH ₃ Is excited as a plasma by the remote plasma unit 37 so as to flow as active species so that it reacts even at the above-mentioned furnace temperature. At this time, while maintaining the pressure in the furnace at a relatively low pressure of 30 to 60 Pa, NH3 which is activated by plasma excitation is supplied for 5 to 120 seconds. What is flowing into the furnace is NH that has been activated by plasma excitation. ₃ Only, there is no DCS. Therefore, NH3 which has been activated by plasma excitation reacts with the underlying film on the substrate W without causing a gas phase reaction.
[0021]
Next, DCS is supplied from the first gas supply pipe 41. At this time, exhaust from the furnace is stopped. Since DCS reacts at the above-mentioned furnace temperature, there is no need for plasma excitation by the remote plasma 37. At this time, the pressure in the furnace is increased to 266 to 931 Pa, which is higher than that of NH3. By supplying DCS, NH3 on the underlayer and DCS undergo a surface reaction, and Si ₃ N ₄ A film is formed.
[0022]
NH described above ₃ The step of alternately flowing DCS and DCS is defined as one cycle. By repeating this cycle, a predetermined thickness of Si ₃ N ₄ A film is formed. In the ALD method, since two gases contributing to film formation do not exist in the gas phase at the same time, the gas is adsorbed on the base surface and reacts with the base film. For this reason, a film having good adhesion to the base film can be obtained, and interface defects can be reduced as compared with the case where the film is formed by a CVD (Chemical Vapor Deposition) method in which two kinds of gases are passed simultaneously. In addition, since NH3 gas requiring plasma excitation among a plurality of types of gases is caused to flow as active species by plasma excitation, film formation can be performed at a reaction temperature of DCS gas which does not require plasma excitation. The film can be formed at a low temperature of ° C.
[0023]
In a general vertical CVD apparatus, for example, when DCS gas, which is a film forming gas, is supplied, it is supplied while controlling the amount of exhaust from the reaction chamber, but if the exhaust from the reaction chamber is stopped here. In addition, the film thickness on the substrate on the upstream side of the DCS gas supply increases, and the film thickness on the substrate decreases on the downstream side of the DCS gas supply, so that the film thickness uniformity among a plurality of wafers is improved. There is a possibility that it will be significantly reduced. In addition, if the film formation gas is supplied without exhausting, it may cause generation of particles, and the supply of the film formation gas without exhausting the gas has not been performed. When the process gas is supplied to the chamber, it is supplied while controlling the exhaust amount from the reaction chamber.
[0024]
However, as a result of diligent research and repeated experiments, the above-described batch type vertical ALD apparatus of the present invention has good uniformity among a plurality of wafers even when the evacuation from the reaction chamber is stopped, and has a problem of particle generation. Was also found to not occur. Further, in the batch type vertical ALD apparatus of the present invention, since a large number of substrates (100 to 150) are processed at one time, the volume of the reaction chamber is smaller than that of a single-wafer processing in which 1 to 3 substrates are processed. When the pressure is increased from the reduced pressure state in which the reaction chamber is evacuated, the exhaust from the exhaust pipe 40 is stopped. Therefore, the gas pressure can be increased in a short time. The speed of adsorption and reaction has been increased, and the processing efficiency of the substrate has been significantly improved.
[0025]
Further, in the vertical ALD apparatus of the present embodiment, in addition to the basic configuration of FIG. 6, a gas reservoir 21 is provided in the first supply pipe 41 as shown in FIG. I am trying to supply.
[0026]
Hereinafter, the configuration of FIG. 1 will be described in detail. The vertical ALD apparatus has a vertical reaction furnace 20 for processing a large number of stacked substrates W. An exhaust pipe 40 that communicates with the vacuum pump 26 to exhaust the reactor 20, a first supply pipe 41 that supplies DCS to the reactor 20, ₃ And a second supply pipe 38 that supplies plasma to the reaction furnace 20 as active species by exciting plasma.
[0027]
A gas reservoir 21 for storing DCS is provided in the first supply pipe 41 for flowing DCS. The gas reservoir 21 is formed of, for example, a gas tank or a spiral pipe having a larger gas capacity than ordinary pipes.
[0028]
A first gas supply valve 22 for opening and closing a pipe is provided in a first supply pipe 41 on the upstream side of the gas reservoir 21, and a second gas supply valve 23 for opening and closing the pipe in a first supply pipe 41 on the downstream side. By opening and closing the first gas supply valve 22 or the second gas supply valve 23, DCS gas as a first type of gas is stored in the gas reservoir 21 via the first supply pipe 41, and the stored DCS gas is discharged. It can be supplied to the reaction furnace 20. The second supply pipe 38 has NH for opening and closing the pipe. ₃ The gas supply valve 24 is provided on the upstream side of the remote plasma unit 37, and by opening and closing the gas supply valve 24, NH as the second type gas is ₃ The gas can be supplied to the reaction furnace 20 or the supply can be stopped. The exhaust pipe 40 is provided with an exhaust valve 25 that opens and closes a pipe line and adjusts the degree of opening. By opening and closing the exhaust valve 25, the reaction furnace 20 can be exhausted or the exhaust can be stopped. Further, by adjusting the opening degree of the exhaust valve 25, the reactor 20 can be exhausted while being maintained at a predetermined pressure. The first supply pipe 41 and the second supply pipe 38 are provided with MFCs (mass flow controllers) 27 and 28, respectively, so as to control the gas flow rates flowing through the first supply pipe 41 and the second supply pipe 38. . In addition, the exhaust valve 25 may be configured as a single valve having a function of opening and closing and adjusting the opening degree, or may be configured as a plurality of valves including a valve having an opening and closing function and a valve having an opening degree adjusting function. .
[0029]
Further, a control means 29 for controlling the pump 26, the valves 22 to 25, a heater (not shown) and the like is provided. The control means 29 controls the exhaust valve 25 and the gas supply valves 22 to 24 to flow the DCS gas through the first supply pipe 41 and store the DCS gas in the gas reservoir 21. The substrate W is exposed to the DCS gas by supplying the DCS gas stored in the reactor to the reaction furnace 20 to raise the pressure in the reaction furnace 20. Further, while the reactor 20 is evacuated by the vacuum pump 26, ₃ By supplying gas to the reaction furnace 20 from the second supply pipe 38 via the remote plasma unit 37, NH 3 ₃ The substrate W is exposed to active species obtained by exciting the gas by plasma.
[0030]
Next, DCS and NH will be described with reference to FIGS. ₃ An example of gas supply will be described. Note that valves filled with black are closed, and valves not filled are open. First, the substrate W on which a film is to be formed is loaded into the boat 39, and is carried into the furnace. After loading, the following three steps are sequentially executed.
[0031]
In step 1 shown in FIG. ₃ The gas and the DCS gas that does not require plasma excitation flow in parallel. First, the valve 24 provided on the gas supply pipe 38 and the exhaust valve 25 provided on the exhaust pipe 40 are both opened, and NH ₃ Is plasma-excited by the remote plasma unit 37 to be exhausted from the exhaust pipe 40 while being supplied into the furnace 20 as active species. NH ₃ When the gas is excited as plasma to flow as active species, the exhaust valve 25 is appropriately adjusted to set the furnace pressure to 10 to 100 Pa, more preferably 30 to 60 Pa. NH controlled by MFC27 ₃ Is 1000 to 10000 sccm. NH ₃ When the gas is excited by plasma to flow as active species, if the exhaust valve 25 provided on the exhaust pipe 40 is closed to stop the vacuum exhaust, NH ₃ Since the activated species activated by plasma excitation of the gas are deactivated before reaching the substrate W, there is a problem that no reaction occurs with the surface of the substrate W. ₃ When the gas is excited as plasma to flow as active species, it is necessary to open the exhaust valve 25 and exhaust the reaction furnace 20. NH ₃ The active species activated by the plasma excitation of the gas are flowed at a large flow rate, and the gas is evacuated to a vacuum of 10 to 100 Pa, more preferably 30 to 60 Pa. Can membrane. Substrate W is NH ₃ Is exposed to the active species obtained by plasma excitation for 2 to 120 seconds. The furnace temperature at this time is set at 350 to 600 ° C. Since the reaction temperature of NH3 is high, it does not react at the above-mentioned furnace temperature, and is caused to flow as active species by exciting the plasma with the remote plasma unit 37 downstream of the valve 24. It can be performed in the temperature range.
[0032]
This NH ₃ Is supplied as an active species by plasma excitation, the upstream valve 22 of the gas supply pipe 41 is opened, the downstream valve 23 is closed, and DCS is caused to flow. Thereby, DCS is stored in the gas reservoir 21 provided between the valves 22 and 23. At this time, the gas flowing into the furnace 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 substrate W.
[0033]
In step 2 shown in FIG. 3, the valve 24 of the gas supply pipe 38 is closed to ₃ Is stopped, but the supply to the gas reservoir 21 is continued. When a predetermined pressure and a predetermined amount of DCS have accumulated in the gas reservoir 21, the upstream valve 22 is also closed, and the DCS is confined in the gas reservoir 21. The furnace is evacuated to 20 Pa or less while the exhaust valve 25 of the exhaust pipe 40 is kept open, and residual NH is exhausted. ₃ From the furnace. At this time, N ₂ When an inert gas such as ₃ Is removed from the furnace. DCS is stored in the gas reservoir 21 so that the pressure becomes 20000 Pa or more. Further, the conductance between the gas reservoir 21 and the reactor 20 is 1.5 × 10 ^-3 m ³ / S or more. Also, considering the ratio between the volume of the reaction chamber and the volume of the gas reservoir required for this, in the case of a reaction chamber volume of 100 l, it is preferably 100 to 300 cc. It is preferable to make it 1/1000 to 3/1000 times.
[0034]
In Step 3 shown in FIG. 4, when the exhaust in the furnace is completed, the valve 25 of the exhaust pipe 40 is closed to stop the exhaust. The valve 23 on the downstream side of the first gas supply pipe 41 is opened. Thereby, the DCS stored in the gas reservoir 21 is supplied into the furnace 20 at once. At this time, since the valve 25 of the exhaust pipe 40 is closed, the pressure in the furnace rapidly rises and rises to about 931 Pa (7 Torr). The time for supplying DCS was set to 2 to 4 seconds, and then the time of exposure to the elevated pressure atmosphere was set to 2 to 4 seconds, for a total of 6 seconds. The furnace temperature at this time is NH ₃ The temperature is 350 to 600 ° C. as in the case of the supply. Due to the supply of DCS, NH3 on the underlying film and DCS undergo a surface reaction, and Si ₃ N ₄ A film is formed. After the film formation, the valve 23 is closed, the valve 25 is opened, and the inside of the reaction furnace 20 is evacuated, and the gas that has contributed to the remaining DCS film formation is removed from the furnace. At this time, N ₂ When an inert gas such as is supplied into the furnace, the effect of eliminating the remaining gas that has contributed to the film formation of DCS from the furnace increases. Further, the valve 22 is opened to start supplying DCS to the gas reservoir 21.
[0035]
Steps 1 to 3 are defined as one cycle, and this cycle is repeated a plurality of times to form a Si film having a predetermined thickness on the substrate. ₃ N ₄ A film is formed.
[0036]
In the ALD apparatus, the gas is adsorbed on the surface of the base film. The amount of gas adsorbed is proportional to the gas pressure and the gas exposure time. Therefore, in order to adsorb a desired constant amount of gas in a short time, it is necessary to increase the gas pressure in a short time. In this regard, in this embodiment, since the DCS stored in the gas reservoir 21 is instantaneously supplied after the exhaust valve 25 is closed, the pressure of the DCS in the furnace can be rapidly increased. Thus, a desired constant amount of gas can be instantaneously adsorbed.
[0037]
Further, in the present embodiment, while DCS is stored in the gas reservoir 21, NH is a necessary step in the ALD method. ₃ Since the gas is supplied as active species by plasma excitation and the furnace is evacuated, no special step for storing DCS is required. Further, the inside of the furnace is evacuated and NH ₃ Since DCS is flowed after removing the gas, both do not react on the way to the substrate. The supplied DCS can effectively react only with NH3 adsorbed on the substrate W.
[0038]
FIG. 5 is a diagram showing the relationship between the amount of adsorption and the film forming speed, and shows a device configuration to which the invention is applied in which DCS is boosted and supplied using a gas reservoir, and a conventional device configuration which supplies DCS while controlling exhaust gas. FIG. The horizontal axis represents the amount of adsorbed gas molecules L (Langmuir: product of gas pressure and gas exposure time), and the vertical axis represents the film thickness (angstrom / cycle) per cycle. Comparing the film formation rates per cycle, even if the gas molecule adsorption amount L (Langmuir) is the same, the invention apparatus can increase the film thickness per cycle compared to the conventional apparatus. Comparing the gas exposure time for the same film thickness, for example, the data A in the case of implementing the apparatus configuration of the present invention has L of 0.38 and a thickness of 1.009 Å / cycle. The data B in the case of the implementation with the corresponding conventional device configuration has L of 1.86 and a thickness of 1.003 Å / cycle. Since the thicknesses of the data A and the data B are almost equal and the pressure is the same, the gas exposure time of the data A is about 1/5 times that of the data B, and the throughput of the present invention is greatly improved. Understand.
[0039]
Accordingly, when the pressure is increased, the film forming rate is increased, and in a process in which the reaction chamber is repeatedly evacuated and then supplied with the process gas as in ALD, the pressure is increased by using a gas reservoir as in the embodiment. This can greatly increase the throughput compared to those that do not. In particular, in a vertical ALD apparatus in which the furnace volume is large and the reaction chamber is evacuated once and the process gas is supplied repeatedly to form a film, in order to increase the throughput, a gas reservoir is provided to increase the pressure instantaneously. It is essential to do.
[0040]
In the above-described embodiment, the case where one gas tank or one spiral pipe is provided as a gas reservoir has been described. However, the present invention is not limited to this, and a plurality of them may be provided in parallel. Further, the gas reservoir of the present invention is not limited to a gas tank or a spiral pipe, and may be any means as long as the gas can be retained and released at a stretch. For example, the DCS supply pipe may be made thicker than usual, and the capacity of the MFC may be increased accordingly. Further, a plurality of DCS supply pipes may be provided. In this case, the number of cylinders serving as DCS supply sources may be increased according to the number of supply pipes. Since DCS has a low vapor pressure, the cylinder may be heated to increase the amount of DCS vaporized. Further, DCS may be forcibly fed into the furnace by a pump.
[0041]
In the above-described embodiment, the present invention is applied to a vertical semiconductor manufacturing apparatus. However, the present invention can be applied to a semiconductor device manufacturing method. In the method of manufacturing a semiconductor device, for example, in a method of manufacturing a semiconductor device in which a substrate stacked in a reaction chamber is processed by repeatedly evacuating a reaction chamber and supplying a process gas to the reaction chamber, a first type of gas is used. A first type of gas is stored in the middle of the supply path through which the gas flows, and while the exhaust from the reaction chamber is stopped, the first type of gas stored in the middle of the supply path is supplied to the reaction chamber to increase the pressure. The state may be such that a film is formed on a substrate. According to this, the first type gas stored in the gas reservoir is supplied to the reaction chamber in a state where the exhaust is stopped, so that the first type gas is instantaneously supplied to the reaction chamber. Can be boosted. Therefore, even in a vertical reaction chamber having a large volume, when switching from evacuation of the reaction chamber to supply of process gas to the reaction chamber, the pressure in the reaction chamber can be increased without delay, and adsorption to the substrate, The film forming speed can be increased, and the throughput can be greatly improved.
[0042]
【The invention's effect】
According to the present invention, a gas reservoir is provided so that a gas that needs to be pressurized can be instantaneously pressurized, so that the throughput can be improved even in a vertical semiconductor manufacturing apparatus having a large gas capacity.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a vertical semiconductor manufacturing apparatus according to an embodiment.
FIG. 2 shows DCS and NH according to an embodiment. ₃ Is a gas supply example of NH 3 ₃ FIG. 4 is an explanatory view showing steps of exhausting while supplying DC into a furnace and storing DCS in a gas reservoir.
FIG. 3 shows DCS and NH according to an embodiment. ₃ FIG. 4 is an explanatory diagram showing a step of exhausting the inside of a furnace and continuously storing DCS in a gas reservoir, which is an example of the gas supply of FIG.
FIG. 4 shows DCS and NH according to an embodiment. ₃ FIG. 4 is an explanatory diagram showing a step of closing the exhaust valve and supplying DCS in a gas reservoir into the furnace, in the gas supply example of FIG.
FIG. 5 is a comparative characteristic diagram showing the relationship between the amount of adsorption and the film formation rate, in comparison with the conventional art and the present invention.
FIG. 6 is a schematic configuration diagram of a vertical ALD apparatus according to an embodiment.
FIG. 7 is a schematic configuration diagram of a conventional ALD apparatus.
[Explanation of symbols]
21 Gas pool
20 Reaction chamber (furnace)
22-25 valve
26 pump
38 Second supply pipe
40 exhaust pipe
41 1st supply pipe
W substrate

Claims (4)

A vertical reaction chamber containing a plurality of stacked substrates,
An exhaust path for exhausting the reaction chamber;
Vacuum exhaust means for exhausting the reaction chamber through the exhaust path,
An exhaust valve for opening and closing the exhaust path;
A first supply path for supplying a first type of gas contributing to film formation to the reaction chamber;
A second supply path that supplies a second type of gas that contributes to the film formation to the reaction chamber;
A gas supply valve for opening and closing the first and second supply paths;
When the first type of gas is supplied to the reaction chamber by controlling the exhaust valve and the gas supply valve, the first type of gas is supplied from the first supply path with the exhaust of the reaction chamber stopped. By supplying a gas to the reaction chamber, the plurality of substrates in the reaction chamber are exposed to the first type of gas, and when the second type of gas is supplied to the reaction chamber, the substrate is evacuated by the evacuation unit. By supplying the second type of gas to the reaction chamber through the second supply path while exhausting the reaction chamber, the plurality of substrates in the reaction chamber are exposed to the second type of gas. A vertical semiconductor manufacturing apparatus comprising a control unit. 2. The vertical semiconductor manufacturing apparatus according to claim 1, wherein the second type gas is activated by plasma excitation and supplied. 2. The vertical semiconductor manufacturing apparatus according to claim 1, wherein the first type of gas is supplied without being activated by plasma excitation. The first supply path has a gas reservoir for storing the first type of gas,
When supplying the first type of gas to the reaction chamber, the control means causes the first type of gas to flow through the first supply path, store the gas in the gas reservoir, and stop the exhaust of the reaction chamber. Supplying the first type of gas stored in the gas reservoir to the reaction chamber from the gas reservoir to the reaction chamber to expose the plurality of substrates in the reaction chamber to the first type gas. The vertical semiconductor manufacturing apparatus according to claim 1.

Images