JP4961218B2 - Substrate processing apparatus and semiconductor device manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the occurrence of loading effects without changing an introduction flow rate of oxygen-containing gas and hydrogen-containing gas in each case according to the number of substrates and a substrate surface structure when simultaneously processing a plurality of substrates. <P>SOLUTION: A semiconductor device manufacturing method has a step for carrying substrates into a processing chamber, a step for subjecting the substrates to oxidation processing by supplying oxygen-containing gas and hydrogen-containing gas into the processing chamber, and a step for carrying out the substrates from the processing chamber after oxidation processing. In the step for subjecting the substrates to oxidation processing, the following one cycle is repeated several times. The one cycle includes a step for sealing the inside of the processing chamber after reducing pressure inside the processing chamber lower than atmospheric pressure by evacuating the inside of the processing chamber, a step for sealing the inside of the processing chamber again after supplying a prescribed amount of oxygen-containing gas and a prescribed amount of hydrogen-containing gas into the sealed processing chamber, and a step for oxidizing the substrates while maintaining the state. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a substrate processing apparatus for oxidizing a substrate such as a wafer and a method for manufacturing a semiconductor device.

  A substrate processing method for oxidizing a substrate surface by introducing an oxygen-containing gas and a hydrogen-containing gas into a processing chamber whose pressure has been reduced to a pressure lower than atmospheric pressure is a conventional substrate processing method using wet oxidation such as pyrogenic oxidation. In comparison, a high-quality oxide film can be obtained, and the difference in oxidation rate between substrate surfaces having different plane orientations can be greatly reduced. Therefore, for example, application to the manufacture of a semiconductor device having a three-dimensional device structure has progressed. It is out.

In the substrate processing method described above, a support holding a plurality of substrates in multiple stages in the vertical direction is inserted and sealed in the processing chamber, and the sealed processing chamber is decompressed using a vacuum pump provided in the exhaust line. The oxygen-containing gas and the hydrogen-containing gas are continuously introduced from above the processing chamber from the gas supply line, and continuously exhausted from below the processing chamber by using a vacuum pump from the exhaust line. A mixed gas flow of an oxygen-containing gas and a hydrogen-containing gas that flows downward is created, and the oxidation treatment is continuously performed on the substrate (see, for example, Patent Document 1).
WO2005 / 020309 pamphlet

  However, in the above-described substrate processing method, the oxidation rate of the substrate disposed on the downstream side of the gas flow (that is, below the processing chamber) is the same as the oxidation rate of the substrate disposed on the upstream side of the gas flow (that is, above the processing chamber). Sometimes it was slower than the speed. A phenomenon (hereinafter referred to as a loading effect) in which the thickness of the oxide film formed on the substrate gradually decreases from the upstream side to the downstream side of the gas flow may occur.

  As one of the causes of the loading effect, the oxygen-containing gas and the hydrogen-containing gas supplied into the processing chamber are consumed by the oxidation reaction of the substrate disposed on the upstream side (above the processing chamber) of the gas flow, and the gas flow It has been considered that the gas that can contribute to the oxidation reaction becomes deficient as it goes downstream (below the processing chamber), and as a result, the oxidation rate becomes slow.

  Therefore, in order to suppress the deficiency of the hydrogen-containing gas on the downstream side of the gas supply, as described in Patent Document 1 described above, the hydrogen-containing gas provided on the upstream side of the gas supply as well as the oxygen-containing gas supply port A method of additionally arranging at least one hydrogen-containing gas supply port on the middle or downstream side of the gas supply separately from the gas supply port, and replenishing the gas from the gas supply port by the amount deficient. Was also devised.

  However, the gas consumption accompanying the oxidation reaction varies depending on the surface area of the substrate. For this reason, in the method of replenishing consumed gas by adding the gas supply ports described above, the gas supply ports are arranged in accordance with the number of substrates carried into the processing chamber and the device structure formed on the substrate surface. It was necessary to change the flow rate of the gas every time.

  Accordingly, the present invention provides a substrate processing apparatus capable of suppressing the occurrence of a loading effect without changing the gas introduction flow rate in accordance with the number of substrates and the surface structure when processing a plurality of substrates simultaneously. And a method of manufacturing a semiconductor device.

According to one aspect of the invention,
A step of carrying the substrate into the processing chamber, a step of oxidizing the substrate by supplying an oxygen-containing gas and a hydrogen-containing gas into the processing chamber, and a step of unloading the substrate after the oxidation treatment from the processing chamber. And in the step of oxidizing the substrate, the process chamber is evacuated to lower the pressure in the process chamber below atmospheric pressure, and then the process chamber is sealed, and the sealed process chamber is closed. The process of re-sealing the processing chamber after supplying a certain amount of oxygen-containing gas and a certain amount of hydrogen-containing gas and the process of oxidizing the substrate while maintaining the state are defined as one cycle. A method of manufacturing a semiconductor device that is repeated a plurality of times is provided.

According to another aspect of the invention,
A processing chamber for processing a substrate, a support for supporting the substrate in the processing chamber, an oxygen-containing gas supply line for supplying an oxygen-containing gas into the processing chamber, and a hydrogen-containing gas for supplying a hydrogen-containing gas into the processing chamber A supply line; a buffer tank that is provided in the oxygen-containing gas supply line and the hydrogen-containing gas supply line, and stores a certain amount of the oxygen-containing gas and the hydrogen-containing gas; an exhaust line that exhausts the processing chamber; and the exhaust A vacuum pump provided in a line for evacuating the processing chamber; means for closing the processing chamber; and evacuating the processing chamber to lower the pressure in the processing chamber below atmospheric pressure, and then closing the processing chamber. A certain amount of oxygen-containing gas and a certain amount of hydrogen-containing gas are stored in the buffer tank, and are stored in the sealed processing chamber from the buffer tank. A controller that repeats this cycle a plurality of times by supplying a certain amount of oxygen-containing gas and a certain amount of hydrogen-containing gas, then resealing the processing chamber and maintaining the state to oxidize the substrate. , A substrate processing apparatus is provided.

According to another aspect of the invention,
A processing chamber for processing a substrate, a support for supporting the substrate in the processing chamber, an oxygen-containing gas supply line for supplying an oxygen-containing gas into the processing chamber, and a hydrogen-containing gas for supplying a hydrogen-containing gas into the processing chamber A supply line; a first buffer tank provided in the oxygen-containing gas supply line for storing a certain amount of the oxygen-containing gas; and a second buffer tank provided in the hydrogen-containing gas supply line for storing a certain amount of the hydrogen-containing gas. An exhaust line for exhausting the processing chamber, a vacuum pump provided in the exhaust line for evacuating the processing chamber, a sealing means for sealing the processing chamber, and evacuating the processing chamber to evacuate the processing chamber After the pressure in the processing chamber is made lower than the atmospheric pressure, the processing chamber is closed, a certain amount of oxygen-containing gas is stored in the first buffer tank, and the second buffer tank After storing a certain amount of hydrogen-containing gas, after supplying a certain amount of oxygen-containing gas from the first buffer tank and a certain amount of hydrogen-containing gas from the second buffer tank into the sealed processing chamber, There is provided a substrate processing apparatus having a controller for re-sealing a processing chamber and maintaining the state to oxidize a substrate and setting this as one cycle to repeat this cycle a plurality of times.

  According to the present invention, when a plurality of substrates are processed simultaneously, the occurrence of a loading effect is suppressed without changing the introduction flow rate of the oxygen-containing gas or the hydrogen-containing gas in accordance with the number of substrates and the surface structure. It is possible to provide a substrate processing apparatus and a method for manufacturing a semiconductor device.

As described above, in the substrate processing method for oxidizing the substrate surface by introducing an oxygen-containing gas and a hydrogen-containing gas into a processing chamber that has been reduced to a pressure lower than atmospheric pressure, the substrate processing method is disposed downstream of the gas flow. A loading effect may occur in which the oxide film thickness formed on the substrate becomes thinner than the oxide film thickness formed on the substrate disposed on the upstream side of the gas flow.
As a cause of the generation of the loading effect, the oxygen-containing gas and the hydrogen-containing gas supplied into the processing chamber are consumed by the oxidation reaction of the substrate disposed on the upstream side of the gas flow and go to the downstream side of the gas flow. It has been thought that the gas that can contribute to the oxidation reaction is deficient as a result, and as a result, the oxidation rate is slow.

  However, the inventor conducted further diligent research on the factor of the loading effect, and found that the factor causing the loading effect is not limited to the above-mentioned factor. That is, it has been discovered that the loading effect is also caused by a pressure deviation (a state in which the partial pressure decreases as it goes downstream of the gas supply) generated in the processing chamber.

  More specifically, since there are structures such as substrates and supports stored in multiple stages in the processing chamber, gas flow resistance inevitably exists. When a flow of oxygen-containing gas and hydrogen-containing gas from one end side to the other end side is created in such a processing chamber, the pressure on the upstream side of the processing chamber is increased due to flow resistance, and the pressure on the downstream side of the processing chamber is A pressure deviation of lowering will occur. On the upstream side of the processing chamber where the partial pressures of the oxygen-containing gas and the hydrogen-containing gas are high, the oxidation rate is increased because the amount of gas that is the raw material for the oxidation treatment is relatively large, while the oxygen-containing gas and the hydrogen-containing gas On the downstream side of the processing chamber where the partial pressure is low, the amount of gas used as the raw material for the oxidation treatment is relatively small, so the oxidation rate is slow. As a result, the loading effect that the oxide film thickness formed on the substrate arranged on the downstream side of the gas flow becomes thinner than the oxide film thickness formed on the substrate arranged on the upstream side of the gas flow occurs. is there.

  That is, in the method of performing oxidation treatment by exhausting while continuously supplying an oxygen-containing gas and a hydrogen-containing gas into a processing chamber where flow resistance exists, a pressure deviation is always generated in the processing chamber due to the flow resistance. Inevitably, a loading effect occurs. The present invention has been made based on these findings found by the inventors.

  Hereinafter, a configuration of a substrate processing apparatus and a substrate processing method according to an embodiment of the present invention will be described in order with reference to the drawings.

(1) Configuration of Substrate Processing Apparatus FIG. 1 is a system configuration schematic diagram of a substrate processing apparatus according to an embodiment of the present invention. A substrate processing apparatus according to an embodiment of the present invention is configured as a batch-type vertical oxidation apparatus that processes a plurality of substrates simultaneously.

<Processing chamber>
As shown in FIG. 1, the substrate processing apparatus according to an embodiment of the present invention includes a reaction tube 10 made of, for example, quartz.

  Inside the reaction tube 10, a processing chamber 2 for processing a silicon wafer 1 as a substrate is formed. A boat 14 as a substrate holder is inserted into the processing chamber 2 from below. The boat 14 is configured to hold a plurality of silicon wafers 1 in a plurality of stages with a gap (substrate pitch interval) in a substantially horizontal state.

  A lower portion of the reaction tube 10 is opened so that the boat 14 can be inserted. The opening provided in the reaction tube 10 is configured to be sealed with a seal cap 18. The boat 14 is mounted on a heat insulating cap 15 that blocks heat conduction from the boat 14. The heat insulating cap 15 is supported from below by the rotating shaft 17. The rotating shaft 17 is provided so as to penetrate the seal cap 18 while maintaining the airtightness in the processing chamber 2. A rotation mechanism 16 that rotates the rotation shaft 17 is provided below the seal cap 18. Therefore, by operating (rotating) the rotation mechanism 16, the boat 14 on which the plurality of silicon wafers 1 are mounted can be rotated while maintaining the hermeticity in the processing chamber 2.

An oxygen gas supply line 3a as an oxygen-containing gas supply line for supplying oxygen gas (O ₂ ) as an oxygen-containing gas and a hydrogen gas (H ₂ ) as a hydrogen-containing gas are supplied to the upper part of the reaction tube 10. A hydrogen gas supply line 3b as a hydrogen-containing gas supply line and a nitrogen gas supply line 3c as an inert gas supply line for supplying nitrogen gas (N ₂ ) as an inert gas are provided. The oxygen gas supply line 3 a, the hydrogen gas supply line 3 b, and the nitrogen gas supply line 3 c merge together at the downstream side, and the unified gas supply line 3 is formed on the ceiling wall of the reaction tube 10. It is connected. A gas outlet is formed at a connection portion of the gas supply line 3 with the reaction tube 10. The gas outlet provided on the ceiling wall of the reaction tube 10 faces downward, and various gases are ejected downward in the processing chamber 2.

<Oxygen gas supply line>
On the upstream side of the oxygen gas supply line 3a, an oxygen gas supply source 4a for supplying oxygen gas (O ₂ ) as an oxygen-containing gas, a mass flow controller 11a as a flow rate control means, and oxygen supplied into the processing chamber 2 A first buffer tank 6a that temporarily stores gas is connected in series in order. A shutoff valve 12a is provided between the oxygen gas supply source 4a and the mass flow controller 11a, and a buffer tank upstream shutoff valve 7a is provided between the mass flow controller 11a and the first buffer tank 6a. A buffer tank downstream side shut-off valve 5 a is provided between 6 a and the ceiling wall of the reaction tube 10.

<Hydrogen gas supply line>
On the upstream side of the hydrogen gas supply line 3b, a hydrogen gas supply source 4b for supplying hydrogen gas (H ₂ ) as a hydrogen-containing gas, a mass flow controller 11b as a flow rate control means, and hydrogen supplied into the processing chamber 2 A second buffer tank 6b for temporarily storing gas is connected in series in order. A shutoff valve 12b is provided between the hydrogen gas supply source 4b and the mass flow controller 11b, and a buffer tank upstream shutoff valve 7b is provided between the mass flow controller 11b and the second buffer tank 6b. A buffer tank downstream side shut-off valve 5b is provided between 6b and the ceiling wall of the reaction tube 10, respectively.

<Nitrogen gas supply line>
On the upstream side of the nitrogen gas supply line 3c, a nitrogen gas supply source 4c for supplying nitrogen gas (N ₂ ) as an inert gas and a mass flow controller 11c as a flow rate control unit are connected in series in order. . A shutoff valve 12c is provided between the nitrogen gas supply source 4c and the mass flow controller 11c, and a shutoff valve 5c is provided between the mass flow controller 11c and the ceiling wall of the reaction tube 10.

<Exhaust line>
An exhaust line 19 for exhausting the processing gas is connected to the lower side of the reaction tube 10. A vacuum pump 9 is connected to the exhaust line 19. During the substrate processing, the inside of the reaction tube 10 is brought to a predetermined pressure (reduced pressure) lower than the atmospheric pressure by the vacuum pump 9. A shutoff valve 8 is provided between the reaction tube 10 and the vacuum pump 9.

<Heater>
Around the reaction tube 10, a resistance heater 13 is disposed as a heating source for heating the inside of the processing chamber 2 from the outside of the reaction tube 10.

<Controller>
The substrate processing apparatus includes shut-off valves 5a to 5c, 7a, 7b, 8, 12a to 12c, mass flow controllers 11a to 11c, a vacuum pump 9, a rotation mechanism 16, and a resistance heater 13.
A controller 20 is provided for controlling the operation of each part constituting the substrate processing apparatus.

(2) Substrate Processing Method Next, as an embodiment of the present invention, a substrate processing method in which an oxidation process is performed on a substrate surface as one step of a semiconductor device manufacturing process will be described with reference to FIG. 2A and 2B are schematic views of an oxidation treatment cycle sequence performed in a substrate processing step according to an embodiment of the present invention, wherein FIG. In addition, an introduction sequence of various gases into the processing chamber is shown.
In addition, the substrate processing method concerning one Embodiment of this invention is implemented by the above-mentioned substrate processing apparatus shown in FIG. In the following description, the operation of each unit constituting the substrate processing apparatus is controlled by the controller 20.

<Board loading process>
First, by operating the resistance heater 13, the temperature in the processing chamber 2 is raised to a predetermined temperature (substrate transport temperature), for example, 300 to 600 ° C., and this state is maintained. Then, a plurality of silicon wafers 1 for batch processing are transferred (loaded) onto the boat 14. Then, the boat 14 loaded with a plurality of silicon wafers 1 is carried into the heated processing chamber 2 and the inside of the processing chamber 2 is sealed with a seal cap 18 (substrate loading step). At this time, the shutoff valves 5a to 5c, 7a, 7b, and 12a to 12c are closed.

<Decompression step>
Next, with the shut-off valves 5c, 7a, 7b, 12a to 12c closed, the shut-off valves 8, 5a, 5b are opened and the vacuum pump 9 is operated, whereby the pressure in the processing chamber 2 and the buffer tanks 6a, 6b is reached. Is reduced to a predetermined pressure lower than atmospheric pressure (101.3 kPa) (S6).

<Temperature raising process>
Next, the resistance heater 13 is operated to raise the temperature in the processing chamber 2 from the substrate transfer temperature when the silicon wafer 1 is carried in to the oxidation treatment temperature (temperature raising step). After completion of the temperature increase, the controller 20 controls the temperature of the entire processing chamber 2 to be stabilized and maintained at the oxidation processing temperature.

<Pressure adjustment process in the processing chamber>
Next, after closing the shut-off valves 5a and 5b, the shut-off valves 12c and 5c are opened, and nitrogen gas (N ₂ ) as an inert gas is supplied (introduced) into the processing chamber 2 while controlling the flow rate by the mass flow controller 11c. To do. At this time, the pressure in the processing chamber 2 is controlled to be a predetermined pressure (processing pressure) by continuously evacuating the processing chamber 2 by the vacuum pump 9 with the shut-off valve 8 open. (S1). The pressure in the processing chamber 2 is adjusted by, for example, controlling the opening degree of the shutoff valve 8 by the controller 20 while the vacuum pump 9 is evacuating the processing chamber 2. In addition, as the pressure in the processing chamber 2 is lower, the time until the partial pressures of the oxygen gas and the hydrogen gas in the processing chamber 2 reach an equilibrium state in an oxygen gas supply process and a hydrogen gas supply process described later is shortened. Therefore, it is desirable to keep the pressure in the processing chamber 2 low in order to suppress the loading effect.

<Oxygen gas supply process to buffer tank>
Next, the shutoff valve 12a and the buffer tank upstream shutoff valve 7a are opened, and a fixed amount of oxygen gas (O ₂ ) as an oxygen-containing gas is filled in the first buffer tank 6a while controlling the flow rate by the mass flow controller 11a. (store). At this time, the shutoff valve 5a is closed. When a certain amount of oxygen gas is filled in the first buffer tank 6a, the buffer tank upstream side shutoff valve 7a is closed to stop the introduction of oxygen gas into the first buffer tank 6a (S1). Then, the shutoff valve 5c is closed to stop the introduction of the N ₂ gas into the processing chamber 2, and the shutoff valve 8 is closed to stop the exhaust of the processing chamber 2 so that the inside of the processing chamber 2 has the above-mentioned predetermined pressure ( (Processing pressure) is maintained (a state between S1 and S2). For convenience, FIG. 2 shows the state between S1 and S2 with time omitted, but in reality, it takes time to maintain the inside of the processing chamber 2 at a predetermined pressure (processing pressure). A predetermined time exists between S1 and S2. At this time, the pressure in the first buffer tank 6a is higher than the pressure in the processing chamber 2.

<Oxygen gas supply process to processing chamber>
Next, by opening the buffer tank downstream side shut-off valve 5a while keeping the buffer tank upstream side shut-off valve 7a closed, the pressure difference between the first buffer tank 6a and the inside of the processing chamber 2 is utilized. A certain amount of oxygen gas stored in the buffer tank 6 a is introduced into the processing chamber 2. When the introduction of a certain amount of oxygen gas into the processing chamber 2 is completed, the buffer tank downstream side shutoff valve 5a is closed (S2).

<Hydrogen gas supply process to buffer tank>
Next, the shutoff valve 12b and the buffer tank upstream shutoff valve 7b are opened, and the second buffer tank 6b is filled with a certain amount of hydrogen gas (H ₂ ) while controlling the flow rate by the mass flow controller 11b. Let (store). At this time, the shutoff valve 5b is closed. When a certain amount of hydrogen gas is filled in the second buffer tank 6b, the buffer tank upstream side shut-off valve 7b is closed to stop introduction of hydrogen gas into the second buffer tank 6b (S3). At this time, the pressure in the second buffer tank 6 b is higher than the pressure in the processing chamber 2. In addition, a certain amount of oxygen gas introduced into the processing chamber 2 is uniformly diffused into the processing chamber 2 to wait for the partial pressure of the oxygen gas in the processing chamber 2 to be in an equilibrium state (S3).

<Hydrogen gas supply process to processing chamber>
Next, by opening the buffer tank downstream side shut-off valve 5b while the buffer tank upstream side shut-off valve 7b is closed, the pressure difference between the second buffer tank 6b and the inside of the processing chamber 2 is utilized. A certain amount of hydrogen gas stored in the buffer tank 6 b is introduced into the processing chamber 2. When the introduction of a certain amount of hydrogen gas into the processing chamber 2 is completed, the buffer tank downstream side shutoff valve 5b is closed (S4).

<Oxidation process>
A certain amount of hydrogen gas introduced into the processing chamber 2 is uniformly diffused into the processing chamber 2 and uniformly mixed with oxygen gas in an equilibrium partial pressure state. Then, the surface of the silicon wafer 1 disposed in the processing chamber 2 reacts with a certain amount of introduced oxygen gas and a certain amount of hydrogen gas, so that the surface of the silicon wafer 1 is oxidized (S5). ).

<Vacuum exhaust process>
After a predetermined time has elapsed, the buffer tank downstream shut-off valve 5a, the buffer tank downstream shut-off valve 5b, and the shut-off valve 8 are opened and remain in the processing chamber 2, the first buffer tank 6a, and the second buffer tank 6b. The oxygen gas and hydrogen gas to be discharged are exhausted by the vacuum pump 9. Thereby, the oxidation reaction in the processing chamber 2 is stopped (S6).

<Repetition process>
The pressure adjusting step in the processing chamber and the oxygen gas supplying step to the buffer tank (S1) → the oxygen gas supplying step to the processing chamber (S2) → the hydrogen gas supplying step to the buffer tank (S3) → to the processing chamber. The hydrogen gas supply step (S4) → oxidation step (S5) → evacuation step (S6) is one cycle, and this cycle is repeated a predetermined number of times to form an oxide film having a desired film thickness on the surface of the silicon wafer 1.

<Cooling process>
After forming the desired oxide film, the shutoff valve 8 is opened and the processing chamber 2 is evacuated by the vacuum pump 9, or the shutoff valves 8, 12c and 5c are opened and the vacuum pump 9 is opened. While the processing chamber 2 is evacuated and purged with nitrogen gas, the temperature in the processing chamber 2 is lowered from the oxidation processing temperature to a predetermined substrate transfer temperature, for example, 300 to 600 ° C.

<Atmospheric pressure leak process>
After the temperature drop in the processing chamber 2 is completed, the shut-off valve 8 is closed and the shut-off valves 12c and 5c are opened to supply nitrogen gas into the processing chamber 2 so that the pressure in the processing chamber 2 is reduced to atmospheric pressure (101 The pressure is increased to 3 kPa).

<Substrate unloading process>
Thereafter, the boat 14 is unloaded from the processing chamber 2 and the oxidized silicon wafer 1 is unloaded. Then, the boat 14 is kept at a predetermined position until all the silicon wafers 1 supported by the boat 14 are cooled. When the silicon wafer 1 held in the waiting boat 14 is cooled to a predetermined temperature, the silicon wafer 1 is recovered by a substrate transfer machine (not shown).

  Thus, the substrate processing process according to the embodiment of the present invention is completed.

  As described above, according to one embodiment of the present invention, the oxidation treatment is not performed by exhausting while continuously supplying the oxygen-containing gas and the hydrogen-containing gas into the processing chamber 2. Pressure adjustment process and oxygen gas supply process to buffer tank (S1) → oxygen gas supply process to process chamber 2 (S2) → hydrogen gas supply process to buffer tank (S3) → hydrogen gas supply to process chamber 2 The process (S4) → oxidation process (S5) → evacuation process (S6) is one cycle, and this cycle is repeated a predetermined number of times to form an oxide film having a desired film thickness on the surface of the silicon wafer 1.

  Therefore, according to one embodiment of the present invention, the surface is formed on the surface of the silicon wafer 1 by arbitrarily changing only the number of cycles without changing conditions such as gas flow rate, supply time, temperature, and pressure. It is possible to easily adjust the thickness of the oxide film. Even when the number of silicon wafers 1 or the device structure formed on the silicon wafer 1 is changed, the film thickness of the oxide film can be arbitrarily controlled by arbitrarily changing only the number of cycles. Is possible. Therefore, it is not necessary to set conditions each time the number of silicon wafers 1 and the device structure formed on the silicon wafer 1 are changed, and the production efficiency can be greatly improved.

  In one embodiment of the present invention, the oxygen-containing gas and the hydrogen-containing gas are not continuously supplied into the processing chamber 2, but a fixed amount of oxygen gas and a fixed amount are supplied into the processing chamber 2 for each cycle. The hydrogen gas is introduced (supplied) and this is repeated. A certain amount of gas supply into the processing chamber 2 is also referred to as flash supply. That is, in one embodiment of the present invention, the oxygen gas flush supply and the hydrogen gas flush supply are repeated for each cycle. Here, since the gas introduced for each cycle instantaneously diffuses throughout the processing chamber 2, the partial pressure of each gas in the processing chamber 2 is in an equilibrium state within a predetermined time (in a very short time). That is, even if a flow resistance exists in the processing chamber 2, in the embodiment of the present invention, gas is not continuously introduced into the processing chamber 2, so that a steady pressure deviation is generated in the processing chamber 2. Is unlikely to occur. Therefore, it is possible to suppress the occurrence of the loading effect.

In one embodiment of the present invention, after a certain amount of oxygen gas is introduced into the processing chamber 2, the process chamber 2 waits until the partial pressure of the oxygen gas in the processing chamber 2 reaches an equilibrium state. A certain amount of hydrogen gas is introduced (supplied). Therefore, the magnitude of the pressure deviation temporarily generated in the processing chamber 2 immediately after the introduction of hydrogen gas can be reduced. Therefore, it is possible to further suppress the occurrence of the loading effect.

In the embodiment of the present invention, since the inside of the processing chamber 2 is evacuated and the pressure is adjusted every cycle, when oxygen gas or hydrogen gas is introduced into the processing chamber 2, the buffer tank 6a is used. , 6b and the processing chamber 2 have a large pressure difference. That is, in the embodiment of the present invention in which the inside of the processing chamber 2 is evacuated and the pressure is adjusted every cycle as compared with the conventional method of continuously supplying the oxygen-containing gas and the hydrogen-containing gas into the processing chamber 2. A larger pressure difference exists between the buffer tanks 6a and 6b and the processing chamber 2.
And, by introducing such oxygen pressure and hydrogen gas from the buffer tanks 6a and 6b into the processing chamber 2 due to the pressure difference, it is possible to improve the speed at which each gas diffuses uniformly throughout the processing chamber 2. It is possible to shorten the time until the partial pressure of each gas in the processing chamber 2 reaches an equilibrium state. As a result, it is possible to suppress the occurrence of the loading effect. As described above, the lower the pressure in the processing chamber 2, the shorter the time until the partial pressure of the oxygen gas and hydrogen gas in the processing chamber 2 reaches an equilibrium state in the oxygen gas supply step and the hydrogen gas supply step. . Therefore, it is desirable to keep the pressure in the processing chamber 2 low to suppress the loading effect.

In one embodiment of the present invention, before introducing oxygen gas and hydrogen gas into the processing chamber 2, the buffer tanks 6a and 6b are filled (stored) with a certain amount of oxygen gas and hydrogen gas. . By increasing the pressure in the buffer tanks 6a and 6b, a larger pressure difference can be generated between the buffer tanks 6a and 6b and the processing chamber 2.
Then, due to the pressure difference, when oxygen gas and hydrogen gas are introduced into the processing chamber 2 from the buffer tanks 6a and 6b, the speed at which each gas uniformly diffuses throughout the processing chamber 2 is further improved. It is possible to further shorten the time until the partial pressure of each gas in the processing chamber 2 reaches an equilibrium state. As a result, the loading effect can be further suppressed.

  In one embodiment of the present invention, before introducing oxygen gas and hydrogen gas into the processing chamber 2, the buffer tanks 6a and 6b are filled (stored) with a certain amount of oxygen gas and hydrogen gas. . Therefore, the amount of gas supplied into the processing chamber 2 for each cycle can be accurately controlled.

  In addition, as a preferable treatment condition of the oxidation treatment in the present embodiment, the oxidation treatment temperature is 600 to 1000 ° C., more preferably 500 to 950 ° C., and the pressure in the treatment chamber in the pressure adjustment step (flash of oxygen gas / hydrogen gas) (Pressure before supply) is 1 Pa or less, process pressure (pressure after oxygen gas / hydrogen gas flush supply) is 1 to 500 Pa, more preferably 10 to 266 Pa, oxygen gas flow rate per cycle is 100 to 1000 cc, 1 cycle The hydrogen gas flow rate per unit is 10 to 500 cc, the number of cycles is 1 to 500 cycles, and the oxide film thickness is 1 to 20 nm. By maintaining a constant value within each range, the silicon wafer 1 is oxidized. The

<Other Embodiments of the Present Invention>
FIG. 3 shows a configuration of a substrate processing apparatus according to another embodiment of the present invention.

In the present embodiment, the oxygen gas supply line 3a is directly connected to the ceiling wall of the reaction tube 10, and the hydrogen gas supply line 3b and the nitrogen gas supply line 3c are joined together at the downstream side. It differs from the substrate processing apparatus according to the above-described embodiment in that the gas supply line 3 which is unified and integrated is connected to the ceiling wall of the reaction tube 10. Other configurations are the same as those of the substrate processing apparatus according to the above-described embodiment.

  The substrate processing process performed by the substrate processing apparatus shown in FIG. 3 is the same as the substrate processing process according to the above-described embodiment.

  Also in the present embodiment, in the case where a plurality of silicon wafers 1 are processed at the same time as in the above-described embodiment of the present invention, the oxygen-containing gas is matched to the number of silicon wafers 1 and the surface structure of the silicon wafer 1. And it becomes possible to suppress generation | occurrence | production of a loading effect, without changing the introduction flow rate of hydrogen-containing gas each time.

  Next, FIG. 4 shows a configuration of a substrate processing apparatus according to another embodiment of the present invention.

  The present embodiment is different from the substrate processing apparatus according to the above-described embodiment in that the mass flow controllers 11a and 11b and the shutoff valves 12a and 12b are not provided. Other configurations are the same as those of the substrate processing apparatus according to the above-described embodiment.

  In the substrate processing step performed by the substrate processing apparatus shown in FIG. 4, the oxygen gas supply step to the buffer tank and the hydrogen gas supply step to the buffer tank are different from the substrate processing step according to the above-described embodiment. Other processes are the same as the substrate processing process according to the above-described embodiment.

That is, as in the substrate processing process according to the above-described embodiment, the inside of the first buffer tanks 6a and 6b is decompressed while the buffer tank upstream side shutoff valves 7a and 7b are closed in the decompression process, In the pressure adjustment step, the buffer tank downstream side shut-off valves 5a and 5b are closed to close the buffer tanks 6a and 6b.

  Thereafter, in the oxygen gas supply step to the buffer tank, the buffer tank upstream side shut-off valve 7a is opened, so that the oxygen gas supply line 3a on the upstream side of the buffer tank upstream side shut-off valve 7a and the first buffer tank Oxygen gas is filled (stored) in the first buffer tank 6a due to the pressure difference from the inside of 6a. Here, by closing the buffer tank downstream side shut-off valve 5a, the upstream oxygen gas supply line 3a and the first buffer tank 6a are in a pressure equilibrium state within a predetermined time. A certain amount of oxygen gas is stored in the buffer tank 6a. A certain amount of oxygen gas may be stored in the first buffer tank 6a by controlling the time for opening the buffer tank upstream side shutoff valve 7a.

  Similarly, in the hydrogen gas supply step to the buffer tank, the buffer tank upstream side shut-off valve 7b is opened, so that the inside of the hydrogen gas supply line 3b upstream of the buffer tank upstream side shut-off valve 7b and the second buffer Due to the pressure difference from the tank 6b, the second buffer tank 6b is filled (stored) with hydrogen gas. Here, by closing the buffer tank downstream side shutoff valve 5b, the upstream hydrogen gas supply line 3b and the second buffer tank 6b are in a pressure equilibrium state within a predetermined time, so that the second A certain amount of hydrogen gas can be stored in the buffer tank 6b. A certain amount of hydrogen gas may be stored in the second buffer tank 6b by controlling the time for opening the buffer tank upstream side shutoff valve 7b.

  Also in the present embodiment, in the case where a plurality of silicon wafers 1 are processed at the same time as in the above-described one embodiment of the present invention, the oxygen-containing gas and the surface structure of the silicon wafer 1 and the surface structure of the silicon wafer 1 are adjusted. It is possible to suppress the occurrence of the loading effect without changing the introduction flow rate of the hydrogen-containing gas each time.

  Next, FIG. 5 shows a configuration of a substrate processing apparatus according to another embodiment of the present invention.

  In the present embodiment, the oxygen gas supply line 3a and the hydrogen gas supply line 3b share a buffer tank, which is different from the substrate processing apparatus according to the above-described embodiment. Further, the point that the mass flow controllers 11a and 11b are not provided is different from the substrate processing apparatus according to the above-described embodiment. Other configurations are the same as those of the substrate processing apparatus according to the above-described embodiment.

  In other words, in the present embodiment, the oxygen gas supply line 3a and the hydrogen gas supply line 3b merge on the downstream side of the shutoff valves 12a and 12b to constitute a unified gas supply line 3d. A buffer tank 6 is provided in the gas supply line 3d. A buffer tank upstream side cutoff valve 7 is provided between the cutoff valves 12a and 12b and the buffer tank 6, and a buffer tank downstream side cutoff valve 5 is provided between the buffer tank 6 and a gas supply line 3 described later. ing. In addition, the downstream side of the buffer tank downstream side shut-off valve 5 in the gas supply line 3d is connected so that the downstream side of the nitrogen gas supply line 3c joins to constitute a unified gas supply line 3. .

  In the substrate processing step performed by the substrate processing apparatus shown in FIG. 5, the oxygen gas supply step to the buffer tank, the oxygen gas supply step to the processing chamber, and the hydrogen gas supply step to the buffer tank are the above-described embodiments. Different from the substrate processing step. Other processes are the same as the substrate processing process according to the above-described embodiment.

  That is, as in the substrate processing process according to the above-described embodiment, the pressure inside the buffer tank 6 is reduced while the buffer tank upstream side shut-off valve 7 is closed in the pressure reducing process, and then the pressure is adjusted in the processing chamber. The downstream shutoff valve 5 is closed and the buffer tank 6 is closed.

  Thereafter, in the oxygen gas supply process to the buffer tank, the shutoff valve 12a and the buffer tank upstream shutoff valve 7 are opened, so that the oxygen gas supply line 3a on the upstream side of the shutoff valve 7 and the buffer tank 6 inside Is filled (stored) with oxygen gas in the buffer tank 6. Here, by closing the buffer tank downstream side shut-off valve 5, the upstream oxygen gas supply line 3a and the buffer tank 6 are in a pressure equilibrium state within a predetermined time. A certain amount of oxygen gas is stored. A certain amount of oxygen gas may be stored in the buffer tank 6 by controlling the time for opening the shutoff valve 12a or the buffer tank upstream shutoff valve 7. When the buffer tank 6 is filled with a certain amount of oxygen gas, the shutoff valve 12a and the buffer tank upstream shutoff valve 7 are closed.

  Thereafter, in the process of supplying oxygen gas to the processing chamber, the buffer tank downstream shut-off valve 5 is opened while the shut-off valves 12a and 12b and the buffer tank upstream shut-off valve 7 are closed. A certain amount of oxygen gas stored in the buffer tank 6 is introduced into the processing chamber 2 using the pressure difference from the inside. When the buffer tank 6 becomes empty, the buffer tank downstream side shutoff valve 5 is closed. When the buffer tank downstream shut-off valve 5 is in the open state, the buffer tank upstream shut-off valve 7 can be opened while the shut-off valves 12a and 12b are closed. Also, the oxygen gas in the upstream gas supply line 3d, the oxygen gas supply line 3a, and the hydrogen gas supply line 3b can be removed. After the oxygen gas supply process to the processing chamber is completed and the buffer tank 6 is emptied, the hydrogen gas supply process to the buffer tank is performed.

In the hydrogen gas supply step to the buffer tank, the shutoff valve 12b and the buffer tank upstream shutoff valve 7 are opened with the buffer tank downstream shutoff valve 5 closed, thereby making the buffer tank upstream shutoff valve 7 more Due to the pressure difference between the upstream hydrogen gas supply line 3 b and the buffer tank 6, the empty buffer tank 6 is filled (stored). Here, by closing the buffer tank downstream side shutoff valve 5, the upstream hydrogen gas supply line 3 b and the buffer tank 6 are in a pressure equilibrium state within a predetermined time. A certain amount of hydrogen gas is stored. A certain amount of hydrogen gas may be stored in the buffer tank 6 by controlling the time for opening the shutoff valve 12b or the buffer tank upstream shutoff valve 7.

  As described above, in the present embodiment, first, oxygen gas is stored in the buffer tank 6 and supplied into the processing chamber 2, then the buffer tank 6 is emptied, and then hydrogen gas is introduced into the emptied buffer tank 6. It is stored and supplied into the processing chamber 2. That is, in this embodiment, oxygen gas and hydrogen gas are alternately stored in one buffer tank 6.

  Also in the present embodiment, in the case where a plurality of silicon wafers 1 are processed at the same time as in the above-described embodiment of the present invention, the oxygen-containing gas is matched to the number of silicon wafers 1 and the surface structure of the silicon wafer 1. And it becomes possible to suppress generation | occurrence | production of a loading effect, without changing the introduction flow rate of hydrogen-containing gas each time.

  Next, FIG. 6 shows a configuration of a substrate processing apparatus according to another embodiment of the present invention.

  In the present embodiment, the oxygen gas supply line 3a and the nitrogen gas supply line 3c merge together at the downstream side, and the unified gas supply line 3 is connected to the ceiling wall of the reaction tube 10. The hydrogen gas supply line 3 b is directly connected to the ceiling wall of the reaction tube 10.

  Further, in the present embodiment, hydrogen supply lines 33b, 43b, and 53b independent from the hydrogen gas supply line 3b are provided. The downstream sides of the hydrogen supply lines 33b, 43b, 53b are a plurality of (multi-system) hydrogen supply nozzles 31b, 41b of different lengths provided in the vertical direction along the inner wall of the side wall of the reaction tube 10 in the processing chamber 2. , 51b, respectively. The hydrogen supply nozzles 31b, 41b, and 51b are configured to have different lengths with respect to the wafer arrangement direction (vertical direction). Further, upstream sides of the hydrogen supply lines 33b, 43b, and 53b are connected to the hydrogen gas supply source 4b, respectively. Buffer tanks 36b, 46b, and 56b are provided in the hydrogen supply lines 33b, 43b, and 53b, respectively. Buffer tank upstream side shut-off valves 37b, 47b, 57b are provided between the hydrogen gas supply source 4b and the buffer tanks 36b, 46b, 56b, respectively. The buffer tanks 36b, 46b, 56b and the hydrogen supply nozzle 31b, Buffer tank downstream shut-off valves 35b, 45b, and 55b are provided between 41b and 51b, respectively. In the present embodiment, the buffer tanks 6b, 36b, 46b, and 56b constitute a second buffer tank. Note that the tips of the hydrogen supply nozzles 31b, 41b and 51b are open, and this open portion serves as a gas supply port. As shown in FIG. 6, the gas supply port may be configured to face the upper side of the processing chamber 2, or may be configured to face the direction (horizontal direction) of the silicon wafer 1. In the present embodiment, the mass flow controllers 11a and 11b and the shutoff valves 12a and 12b are not provided.

  Other configurations are the same as those of the substrate processing apparatus according to the above-described embodiment.

  In the substrate processing process performed by the substrate processing apparatus shown in FIG. 6, the hydrogen gas supply process to the buffer tank and the hydrogen gas supply process to the processing chamber are different from the substrate processing process according to the above-described embodiment. Other processes are the same as the substrate processing process according to the above-described embodiment.

That is, as in the substrate processing process according to the above-described embodiment, the first buffer tank 6a and the second buffer tank 6a are closed while the buffer tank upstream side shut-off valves 7a, 7b, 37b, 47b, and 57b are closed in the pressure reducing process. After decompressing the inside of the buffer tanks 6b, 36b, 46b, 56b, the buffer tank downstream side shut-off valves 5a, 5b, 35b, 45b, 55b are closed in the pressure adjustment step in the processing chamber, and the first buffer tank 6a and the first buffer tank 6a The second buffer tanks 6b, 36b, 46b, 56b are closed.

Thereafter, in the hydrogen gas supply step to the buffer tank, the buffer tank upstream side shutoff valves 7b, 37b, 47b, and 57b are opened, so that the hydrogen upstream of the buffer tank upstream side shutoff valves 7b, 37b, 47b, and 57b is opened. Gas supply lines 3b, 33b, 43b, 53b
The second buffer tanks 6b, 36b, 46b, and 56b are filled (stored) with hydrogen gas by the pressure difference between the inside and the second buffer tanks 6b, 36b, 46b, and 56b, respectively. Here, by closing the buffer tank downstream side shut-off valves 5b, 35b, 45b, 55b, the hydrogen gas supply lines 3b, 33b, 43b, 53b on the upstream side and the second buffer tanks 6b, 36b, 46b, Since the inside of 56b is in a pressure equilibrium state within a predetermined time, a certain amount of hydrogen gas is stored in the second buffer tanks 6b, 36b, 46b, 56b. Further, a certain amount of hydrogen gas may be stored in the second buffer tanks 6b, 36b, 46b, and 56b by controlling the time for opening the buffer tank upstream side shutoff valves 7b, 37b, 47b, and 57b.

Further, in the hydrogen gas supply step to the processing chamber, the second buffer tank downstream side shutoff valves 5b, 35b, 45b, and 55b are opened while the buffer tank upstream side shutoff valves 7b, 37b, 47b, and 57b are closed, so that the second A certain amount of hydrogen gas stored in the second buffer tanks 6b, 36b, 46b, and 56b is converted into the processing chamber 2 by utilizing the pressure difference between the buffer tanks 6b, 36b, 46b, and 56b and the processing chamber 2. Introduce in. When the introduction of a certain amount of hydrogen gas into the processing chamber 2 is completed, the buffer tank downstream side shut-off valves 5b, 35b, 45b, 55b are closed.

  In the hydrogen gas supply process to the processing chamber according to the above-described embodiment, the hydrogen gas introduced into the processing chamber 2 from the hydrogen gas supply line 3b is uniformly diffused in the processing chamber 2 and In some cases, a partial pressure deviation is generated in the processing chamber 2 though it reacts near the gas supply port and is consumed for a very short time. On the other hand, in the present embodiment, the hydrogen supply lines 33b, 43b, 53b independent from the hydrogen gas supply line 3b are provided with hydrogen supply nozzles 31b, 41b, having different lengths with respect to the wafer arrangement direction (vertical direction). Hydrogen gas is introduced into the processing chamber 2 by 51b. Thereby, when the hydrogen gas is supplied into the processing chamber, the above-described partial pressure deviation occurring in the processing chamber 2 for only a very short time can be suppressed, and the generation of the loading effect can be further suppressed. It becomes possible.

  Next, FIG. 7 shows a configuration of a substrate processing apparatus according to another embodiment of the present invention.

  In the present embodiment, the oxygen gas supply line 3a ′, the hydrogen gas supply line 3b ′, and the nitrogen gas supply line 3c ′ join together on the downstream side to form a unified first gas supply line 30 ′. It is connected to the lower side wall of the tube 10. In addition, the second gas supply line 30 is formed by joining the oxygen gas supply line 3a, the hydrogen gas supply line 3b, and the nitrogen gas supply line 3c on the downstream side thereof, and is connected to the upper side wall of the reaction tube 10. Has been. Other configurations are the same as those of the substrate processing apparatus according to the above-described embodiment.

  The substrate processing process performed by the substrate processing apparatus shown in FIG. 7 is a repetitive process in which a gas supply from the first gas supply line 30 ′ and a gas supply from the second gas supply line 30 are performed by a so-called flip-flop. Thus, the point which repeats alternately differs from the substrate processing process concerning one above-mentioned embodiment. Other processes are the same as the substrate processing process according to the above-described embodiment.

  That is, the pressure adjusting process in the process chamber 2 and the oxygen gas supply process to the buffer tank (S1) → the oxygen gas supply process to the process chamber 2 (S2) → the hydrogen gas supply process to the buffer tank (S3) → process After performing the hydrogen gas supply step (S4) → oxidation step (S5) → evacuation step (S6) to the chamber 2 using the first gas supply line 30 ′, the pressure adjustment step in the processing chamber 2, and Oxygen gas supply step to buffer tank (S1) → Oxygen gas supply step to processing chamber 2 (S2) → Hydrogen gas supply step to buffer tank (S3) → Hydrogen gas supply step to processing chamber 2 (S4) → The oxidation step (S5) → evacuation step (S6) is performed by using the second gas supply line 30 as one cycle, and this cycle is repeated a predetermined number of times to oxidize the surface of the silicon wafer 1 to a desired film thickness. film Formation to.

  In the hydrogen gas supply process to the processing chamber according to the above-described embodiment, the hydrogen gas introduced into the processing chamber 2 from the hydrogen gas supply line 3b is uniformly diffused in the processing chamber 2 and In some cases, a partial pressure deviation is generated in the processing chamber 2 though it reacts near the gas supply port and is consumed for a very short time. In contrast, in the present embodiment, in the repetition process, the gas supply from the first gas supply line 30 ′ connected to the lower side wall of the reaction tube 10 and the second gas supply connected to the upper side wall of the reaction tube 10 are performed. Since the gas supply from the line 30 is alternately repeated like a flip-flop, the above-described problem, that is, the above-described partial pressure deviation that occurs in the processing chamber 2 only for a very short time when hydrogen gas is supplied into the processing chamber. It is possible to eliminate the influence of the above and further suppress the occurrence of the loading effect.

In the above, the case where oxygen (O ₂ ) gas is used as the oxygen-containing gas has been described. However, from oxygen (O ₂ ) gas, nitrous oxide (N ₂ O) gas, and nitrogen monoxide (NO) gas At least one gas selected from the group can be used. Further, the description has been given of the case of using hydrogen _{(H 2)} gas as a hydrogen-containing gas, hydrogen _{(H 2)} gas, deuterium (heavy hydrogen) gas, ammonia (NH ₃₎ gas and methane (CH ₄₎ the group consisting of gas At least one gas selected from can be used.

  In the above description, the method of introducing (supplying) the hydrogen gas as the hydrogen-containing gas into the processing chamber 2 after introducing (supplying) the oxygen gas as the oxygen-containing gas into the processing chamber 2 has been described. The present invention is not limited to such an order of introduction. That is, the oxygen-containing gas may be introduced into the processing chamber 2 after the hydrogen-containing gas is introduced into the processing chamber 2. However, the loading effect is noticeable when oxygen gas is introduced into the processing chamber 2 prior to hydrogen gas, particularly when hydrogen gas is introduced into an oxygen-rich atmosphere. If the oxygen-containing gas and the hydrogen-containing gas are uniformly mixed before being supplied into the processing chamber 2, the oxygen-containing gas and the hydrogen-containing gas can be simultaneously supplied into the processing chamber 2. It is.

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

According to one aspect of the invention,
A step of oxidizing the substrate by supplying an oxygen-containing gas and a hydrogen-containing gas into the processing chamber and a step of unloading the substrate after the oxidation processing from the processing chamber; Then, the process chamber is evacuated to lower the pressure in the process chamber below atmospheric pressure, and then the process chamber is sealed, and a certain amount of oxygen-containing gas and a certain amount are sealed in the sealed process chamber. Provided is a method for manufacturing a semiconductor device in which the process of resealing the processing chamber after supplying a hydrogen-containing gas and the process of oxidizing the substrate while maintaining the state are repeated as a single cycle. Is done.

Preferably,
Before supplying the fixed amount of oxygen-containing gas and the fixed amount of hydrogen-containing gas into the processing chamber, the fixed amount of oxygen-containing gas and the fixed amount of hydrogen-containing gas are stored in a buffer tank.

Preferably,
When supplying the fixed amount of oxygen-containing gas and the fixed amount of hydrogen-containing gas into the processing chamber, the fixed amount of oxygen-containing gas is supplied in advance, and then the fixed amount of hydrogen-containing gas is supplied. To do.

Preferably,
When supplying the fixed amount of oxygen-containing gas and the fixed amount of hydrogen-containing gas into the processing chamber, the fixed amount of hydrogen-containing gas is supplied in advance, and then the fixed amount of oxygen-containing gas is supplied. To do.

Preferably,
When supplying the certain amount of oxygen-containing gas and the certain amount of hydrogen-containing gas into the processing chamber, the certain amount of oxygen-containing gas and the certain amount of hydrogen-containing gas are simultaneously supplied.

Preferably,
When supplying the certain amount of oxygen-containing gas and the certain amount of hydrogen-containing gas into the processing chamber, the certain amount of oxygen-containing gas and the certain amount of hydrogen-containing gas are supplied sequentially or simultaneously.

Preferably,
When supplying the predetermined amount of oxygen-containing gas and the predetermined amount of hydrogen-containing gas into the processing chamber, one of the oxygen-containing gas and the hydrogen-containing gas is supplied in advance, After the partial pressure of the gas in the processing chamber reaches an equilibrium state, the other gas is supplied.

Preferably,
The other gas is uniformly mixed with the one gas in an equilibrium partial pressure state in the processing chamber, and the oxidation is performed.

According to another aspect of the invention,
A processing chamber for processing a substrate, a support for supporting the substrate in the processing chamber, an oxygen-containing gas supply line for supplying an oxygen-containing gas into the processing chamber, and a hydrogen-containing gas for supplying a hydrogen-containing gas into the processing chamber A supply line; a buffer tank that is provided in the oxygen-containing gas supply line and the hydrogen-containing gas supply line, and stores a certain amount of the oxygen-containing gas and the hydrogen-containing gas; an exhaust line that exhausts the processing chamber; and the exhaust A vacuum pump provided in a line for evacuating the processing chamber; means for closing the processing chamber; and evacuating the processing chamber to lower the pressure in the processing chamber below atmospheric pressure, and then closing the processing chamber. A certain amount of oxygen-containing gas and a certain amount of hydrogen-containing gas are stored in the buffer tank, and are stored in the sealed processing chamber from the buffer tank. A controller that repeats this cycle a plurality of times by supplying a certain amount of oxygen-containing gas and a certain amount of hydrogen-containing gas, then resealing the processing chamber and maintaining the state to oxidize the substrate. , A substrate processing apparatus is provided.

Preferably,
A first shut-off valve is provided on each of the upstream and downstream sides of the buffer tank in the gas supply line, a second shut-off valve is provided on the exhaust line, and the means for sealing the processing chamber is the gas A first shut-off valve provided on the supply line downstream of the buffer tank; and a second shut-off valve provided on the exhaust line.

According to another aspect of the invention,
A processing chamber for processing a substrate, a support for supporting the substrate in the processing chamber, an oxygen-containing gas supply line for supplying an oxygen-containing gas into the processing chamber, and a hydrogen-containing gas for supplying a hydrogen-containing gas into the processing chamber A supply line; a first buffer tank provided in the oxygen-containing gas supply line for storing a certain amount of the oxygen-containing gas; and a second buffer tank provided in the hydrogen-containing gas supply line for storing a certain amount of the hydrogen-containing gas. An exhaust line for exhausting the processing chamber, a vacuum pump provided in the exhaust line for evacuating the processing chamber, a sealing means for sealing the processing chamber, and evacuating the processing chamber to evacuate the processing chamber After the pressure in the processing chamber is made lower than the atmospheric pressure, the processing chamber is closed, a certain amount of oxygen-containing gas is stored in the first buffer tank, and the second buffer tank After storing a certain amount of hydrogen-containing gas, after supplying a certain amount of oxygen-containing gas from the first buffer tank and a certain amount of hydrogen-containing gas from the second buffer tank into the sealed processing chamber, There is provided a substrate processing apparatus having a controller for re-sealing a processing chamber and maintaining the state to oxidize a substrate and setting this as one cycle to repeat this cycle a plurality of times.

Preferably,
First shut-off valves are respectively provided on the upstream side and the downstream side of the first buffer tank in the oxygen-containing gas supply line, and on the upstream side and the downstream side of the second buffer tank in the hydrogen-containing gas supply line. Are each provided with a second shut-off valve, the exhaust line is provided with a third shut-off valve, and means for sealing the processing chamber is provided downstream of the first buffer tank in the oxygen-containing gas supply line. The first shut-off valve provided, the second shut-off valve provided on the downstream side of the second buffer tank in the hydrogen-containing gas supply line, and the third shut-off valve provided in the exhaust line; including.

According to another aspect of the invention,
A step of carrying the substrate into the processing chamber, a step of oxidizing the substrate by supplying an oxygen-containing gas and a hydrogen-containing gas into the processing chamber, and a step of unloading the substrate after the oxidation treatment from the processing chamber. And in the step of oxidizing the substrate, the process chamber and the buffer tank connected to the process chamber are reduced to a pressure lower than atmospheric pressure and sealed, and the process chamber and the buffer are sealed After closing the second shut-off valve provided between the tank and the buffer tank, the first shut-off valve provided between the gas supply source of each gas is opened to contain the oxygen-containing gas and hydrogen. After the step of storing a certain amount of gas in the buffer tank and the accumulation of the oxygen-containing gas and the hydrogen-containing gas in the buffer tank are completed and the first shut-off valve is closed, the second shut-off valve is opened. The buffer Introducing the oxygen-containing gas and hydrogen-containing gas stored in the tank into the processing chamber to oxidize the substrate surface for a certain period of time, and then evacuating the processing chamber and the buffer tank after oxidizing the substrate surface for a certain period of time. The method of manufacturing a semiconductor device is provided by repeating this cycle a plurality of times.

Preferably,
The buffer tank is provided in each of an oxygen-containing gas supply line for supplying an oxygen-containing gas into the processing chamber and a hydrogen-containing gas supply line for supplying a hydrogen-containing gas into the processing chamber, and the second shutoff valve is provided. Opening introduces the oxygen-containing gas and hydrogen-containing gas stored in the buffer tank into the processing chamber that has been decompressed to a constant pressure lower than atmospheric pressure, and oxidizes the substrate surface.

Preferably,
The oxygen-containing gas is oxygen (O ₂ ) gas, and the hydrogen-containing gas is hydrogen (H ₂ ) gas.

It is a system configuration schematic diagram of a substrate processing apparatus concerning one embodiment of the present invention. It is the schematic of the oxidation process cycle sequence implemented at the substrate processing process concerning one Embodiment of this invention, (a) shows the opening-and-closing sequence of each cutoff valve, (b) is in a buffer tank and a process chamber. The introduction sequence of various gases is shown. It is a system configuration schematic diagram of a substrate processing apparatus concerning other embodiments of the present invention. It is a system configuration schematic diagram of a substrate processing apparatus concerning other embodiments of the present invention. It is a system configuration schematic diagram of a substrate processing apparatus concerning other embodiments of the present invention. It is a system configuration schematic diagram of a substrate processing apparatus concerning other embodiments of the present invention. It is a system configuration schematic diagram of a substrate processing apparatus concerning other embodiments of the present invention.

Explanation of symbols

1 Silicon wafer (substrate)
2 Processing chamber 3a Oxygen gas supply line (oxygen-containing gas supply line)
3b Hydrogen gas supply line (hydrogen-containing gas supply line)
3c Nitrogen gas supply line (inert gas supply line)
5a 1st buffer tank downstream shut-off valve 6a 1st buffer tank 7a 1st buffer tank upstream shut-off valve 5b 2nd buffer tank downstream shut-off valve 6b 2nd buffer tank 7b 2nd buffer tank upstream Shut-off valve 9 Vacuum pump 19 Exhaust line 20 Controller

Claims (5)

Carrying a substrate into the processing chamber;
Supplying oxygen-containing gas and hydrogen-containing gas into the processing chamber to oxidize the substrate;
And carrying out the substrate after oxidation treatment from the processing chamber,
In the step of oxidizing the substrate, the process chamber is evacuated to lower the pressure in the process chamber below atmospheric pressure, and then the process chamber is sealed, and a certain amount of the process chamber is sealed. The cycle of repeating the process a plurality of times, comprising a step of sealing the processing chamber again after supplying the oxygen-containing gas and a certain amount of hydrogen-containing gas and a step of oxidizing the substrate while maintaining the state. A method for manufacturing a semiconductor device.   The predetermined amount of oxygen-containing gas and the predetermined amount of hydrogen-containing gas are stored in a buffer tank before supplying the predetermined amount of oxygen-containing gas and the predetermined amount of hydrogen-containing gas into the processing chamber. Item 14. A method for manufacturing a semiconductor device according to Item 1.   When supplying the fixed amount of oxygen-containing gas and the fixed amount of hydrogen-containing gas into the processing chamber, the fixed amount of oxygen-containing gas is supplied in advance, and then the fixed amount of hydrogen-containing gas is supplied. A method for manufacturing a semiconductor device according to claim 1. A processing chamber for processing the substrate;
A support for supporting the substrate in the processing chamber;
An oxygen-containing gas supply line for supplying an oxygen-containing gas into the processing chamber;
A hydrogen-containing gas supply line for supplying a hydrogen-containing gas into the processing chamber;
A buffer tank that is provided in the oxygen-containing gas supply line and the hydrogen-containing gas supply line, and stores a certain amount of the oxygen-containing gas and the hydrogen-containing gas;
An exhaust line for exhausting the processing chamber;
A vacuum pump provided in the exhaust line for evacuating the processing chamber;
Means for sealing the processing chamber;
The process chamber is evacuated to lower the pressure in the process chamber below atmospheric pressure, and then the process chamber is closed, and a certain amount of oxygen-containing gas and a certain amount of hydrogen-containing gas are stored in the buffer tank, After supplying a certain amount of oxygen-containing gas and a certain amount of hydrogen-containing gas from the buffer tank to the sealed processing chamber, the processing chamber is sealed again, and this state is maintained to oxidize the substrate. A controller that repeats this cycle multiple times as one cycle,
A substrate processing apparatus. A processing chamber for processing the substrate;
A support for supporting the substrate in the processing chamber;
An oxygen-containing gas supply line for supplying an oxygen-containing gas into the processing chamber;
A hydrogen-containing gas supply line for supplying a hydrogen-containing gas into the processing chamber;
A first buffer tank provided in the oxygen-containing gas supply line and storing a fixed amount of the oxygen-containing gas;
A second buffer tank provided in the hydrogen-containing gas supply line and storing a certain amount of the hydrogen-containing gas;
An exhaust line for exhausting the processing chamber;
A vacuum pump provided in the exhaust line for evacuating the processing chamber;
Sealing means for sealing the processing chamber;
The processing chamber is evacuated to reduce the pressure in the processing chamber to less than atmospheric pressure, and then the processing chamber is closed, a predetermined amount of oxygen-containing gas is stored in the first buffer tank, and the second buffer tank is stored. A predetermined amount of hydrogen-containing gas is stored in the sealed processing chamber, a certain amount of oxygen-containing gas is supplied from the first buffer tank, and a certain amount of hydrogen-containing gas is supplied from the second buffer tank. Re-sealing the processing chamber, maintaining the state to oxidize the substrate, taking this as one cycle, and repeating this cycle multiple times;
A substrate processing apparatus.

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