TWI715736B - Film forming device and film forming method - Google Patents

Abstract

The present invention provides a film forming device and a film forming method that can reduce the film-forming substance attached to the pressure sensor and prolong the life of the pressure sensor. The raw material gas supply part is used for the film forming process to supply the raw material gas containing the film forming components to the film forming chamber 10, and the second gas pipe 90 is used for the film forming process, and the process gas different from the raw material gas is stored in the process The gas processing gas storage part is supplied to the film forming chamber 10. The pressure sensor 50 that measures the pressure inside the film forming chamber 10 is attached to the second gas pipe 90. The control unit performs control to cause the processing gas to flow into the second gas pipe 90 from the processing gas storage unit to be supplied to the film formation chamber 10 while the material gas is supplied from the material gas supply unit to the film formation chamber 10.

Description

Film forming device and film forming method

The invention relates to a film forming device and a film forming method for performing film forming processing on a workpiece.

As a film forming device for forming a thin film on a workpiece, especially on the surface of a substrate, there are a Chemical Vapor Deposition (hereinafter referred to as "CVD") device and an Atomic Layer Deposition (hereinafter referred to as "ALD") device . A CVD device is a device that uses heat or plasma to decompose the material gas and deposit it on the surface of the substrate. The ALD device is a device that alternately supplies gases composed of the elements constituting the film to the substrate as the film formation target, and forms a thin film on the surface of the substrate in units of atomic layers.

In order to perform an appropriate film forming process in the film forming device, the film forming device is equipped with a pressure sensor that detects the pressure in the film forming chamber. The pressure sensor is provided on the gas discharge side of the film forming chamber as shown in Patent Document 1, for example.

The prior art documents include Patent Document 1: Japanese Patent Laid-Open No. 2003-273031.

In the film forming apparatus described in Patent Document 1, the residual gas in the reaction chamber and the residual gas system in the pipe equipped with the pressure sensor are supplied with flushing gas into the reaction chamber and discharged to the outside after the film forming process is completed. However, since the pressure sensor is provided on the exhaust side of the gas of the film forming device, the film-forming substance contained in the exhausted residual gas will adhere to the pressure sensor.

Because the film-forming substance adheres to the pressure sensor, the life of the pressure sensor is shortened, and the pressure sensor must be replaced frequently. In addition, when the pressure sensor is used for cleaning, a cleaning operation for removing the attached film-forming substance is required.

The present invention is completed in view of the above-mentioned facts, and its purpose is to provide a film forming device and a film forming method that can reduce the film-forming substances attached to the pressure sensor and prolong the life of the pressure sensor.

A film forming apparatus according to a first aspect of the present invention includes: a film forming chamber in which a film forming process is performed on a workpiece; and a raw material gas supply part used for the film forming process described above, and a raw material gas containing film forming components is supplied to The film forming chamber; a gas piping used for the film forming process to supply a process gas different from the raw material gas to the film forming chamber from a process gas storage section storing the process gas; a pressure sensor, which is installed in The gas piping measures the pressure inside the film forming chamber; and a control unit which controls so that the source gas is supplied from the source gas supply unit During the period to the film formation chamber, the processing gas is caused to flow into the gas piping from the processing gas storage portion to be supplied to the film formation chamber.

The gas piping may be provided with a regulating valve that adjusts the flow rate of the processing gas supplied from the processing gas storage unit to the film forming chamber, and the control unit controls the source gas from the source gas supply unit During the supply to the film forming chamber, the adjustment valve is opened.

The pressure sensor may be installed further downstream than the adjustment valve of the gas piping.

The processing gas may also be a reaction gas or carrier gas that reacts with the raw material gas.

The pressure sensor described above may also be a diaphragm pressure sensor.

It may further include a flushing gas supply part that supplies flushing gas to the film forming chamber, the pressure sensor is a pressure sensor that measures whether the pressure in the film forming chamber is atmospheric pressure, and the control part controls the pressure When the sensor measures that the pressure in the film formation chamber is atmospheric pressure, the supply of the washing gas supplied from the washing gas supply part to the film formation chamber is stopped.

It may further include a gas shower connected to the downstream end of the gas piping, arranged facing the workpiece in the film forming chamber, and having a plurality of facing surfaces formed on the facing surface facing the workpiece The spray hole and the gas shower supply the processing gas supplied from the gas pipe to the surface of the workpiece in a shower shape from the spray hole.

The film forming method of the second aspect of the present invention includes: a raw material gas supply step of supplying a raw material gas containing a film forming component to the film forming chamber to adsorb the raw material gas on the surface of the workpiece; a first flushing step of supplying a flushing gas , The residual gas remaining in the film forming chamber is flushed; the thin film forming step, after the first flushing step, the reaction gas and the carrier gas that react with the raw material gas enter the gas equipped with the pressure sensor Piping and supplied to the film forming chamber to generate plasma of the reactive gas, react the raw material gas adsorbed on the surface of the workpiece with the plasma of the reactive gas to form a thin film on the surface of the workpiece, and the pressure sensor Measuring the pressure in the film forming chamber; and a second flushing step of supplying the flushing gas after the thin film forming step, flushing the residual gas remaining in the film forming chamber, and in the raw material gas supplying step, The reaction gas or the carrier gas flows into the gas pipe and is supplied to the film formation chamber.

In the thin film forming step, the reaction gas and the carrier gas may always flow into the gas pipe.

In the first flushing step and the second flushing step, the reaction gas or the carrier gas may be introduced into the gas piping to be supplied to the process as the flushing gas. Membrane chamber.

According to the present invention, it is possible to provide a film forming device and a film forming method that reduce the film-forming substance attached to the pressure sensor and extend the life of the pressure sensor.

1‧‧‧Film forming device

10‧‧‧Film forming room

20‧‧‧Gas Storage Department

21‧‧‧Raw gas storage department

21a‧‧‧First gas piping

21b‧‧‧The first adjusting valve

22‧‧‧Reactive gas storage

22b‧‧‧Second regulating valve

23‧‧‧Carrier Gas Storage

23b‧‧‧The third adjusting valve

24‧‧‧Flushing gas storage

24a‧‧‧3rd gas piping

24b‧‧‧4th adjusting valve

30‧‧‧High frequency power supply

31‧‧‧First electrode

32‧‧‧Second electrode

40‧‧‧Heater

50‧‧‧Pressure sensor

60‧‧‧Vacuum pump

61‧‧‧Exhaust pipe

70‧‧‧Controller

80‧‧‧Substrate

90‧‧‧Second gas piping

100‧‧‧Gas shower

101‧‧‧Opposite

102‧‧‧Ejection hole

120‧‧‧4th gas piping

Fig. 1 is a conceptual diagram of a film forming apparatus according to Embodiment 1 of the present invention.

Fig. 2 is a diagram showing the first time chart of the film forming process.

Fig. 3 is a diagram showing a second time chart of the film forming process.

Fig. 4 is a diagram showing a third time chart of the film forming process.

Fig. 5 is a diagram showing the fourth time chart of the film forming process.

Figure 6 is a diagram showing a flow chart of the film forming process.

Fig. 7 is a conceptual diagram of a film forming apparatus according to Embodiment 2 of the present invention.

Hereinafter, the embodiment of the film forming apparatus 1 of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)

The film forming apparatus 1 of the embodiment of the present invention will be described with reference to FIGS. 1 to 6. In this embodiment, as the film forming device 1, an ALD device is used, and in particular, plasma atomic layer deposition (Plasma enhanced ALD, in which an organic metal gas reacts with oxygen plasma to form an oxide film) is used. (Hereinafter referred to as "PE-ALD") device for description.

The film forming device 1 is a PE-ALD device that applies the PE-ALD method to generate an oxide film. In the PE-ALD method, first, an organic metal raw material gas mainly composed of the metal constituting the film to be formed is supplied to the substrate, and the raw material gas is chemically adsorbed (saturated adsorption) on the substrate. The raw material gas is absorbed by only one layer on the substrate by the self-limiting function. Then, the unreacted raw material gas and reaction products are flushed. Then, a reaction gas that reacts with the raw material gas, such as oxygen, is supplied to the film forming chamber 10, and oxygen plasma is generated using the oxygen. The generated oxygen plasma oxidizes the components of the raw material gas adsorbed on the substrate. Then, the unreacted reaction species and reaction products are washed. These treatments are regarded as one cycle, and a film of a predetermined thickness is formed on the substrate by repeating the treatment of a plurality of cycles.

As shown in FIG. 1, the film forming apparatus 1 of this embodiment includes a film forming chamber 10, a gas storage unit 20, a high-frequency power supply 30, a heater 40, a pressure sensor 50, a vacuum pump 60 and a controller 70.

The film forming chamber 10 is a vacuum chamber that contains a substrate 80 as a workpiece. In the film forming chamber 10, a film forming process is performed on the surface of the substrate 80 in a vacuum environment.

The gas storage portion 20 includes a raw material gas storage portion 21, a reaction gas storage portion 22, a carrier gas storage portion 23 and a flushing gas storage portion 24. In this embodiment, the reaction gas storage part 22 and the carrier gas storage part 23 correspond to the "processing gas storage part". The flushing gas storage part 24 can also be combined as a "processing gas storage part".

The source gas storage part 21 is a container for storing source gas, and is connected to the film forming chamber 10 via a first gas pipe 21a. In this embodiment, trimethylaluminum (TMA) gas is used as the source gas. The first gas piping 21a is provided with a first adjustment valve 21b that adjusts the flow rate of the raw material gas supplied from the raw material gas storage part 21 to the film forming chamber 10. According to the preset flow Adjust the opening of the first regulating valve 21b.

The raw material gas system is used as a precursor (precursor) in the PE-ALD device, and the liquid raw material is vaporized and supplied to the film forming chamber 10 from the raw material gas storage part 21.

The reaction gas storage part 22 is a container for storing the reaction gas that reacts with the raw material gas. In this embodiment, oxygen is used as the reaction gas. The oxygen gas becomes oxygen plasma by the voltage applied by the high-frequency power supply 30 and reacts with the raw material gas chemically adsorbed on the substrate.

The carrier gas storage part 23 is a container for storing the carrier gas that transports the raw material gas or the reaction gas into the film forming chamber 10. The carrier gas uses a gas that is inert to the raw material gas or reaction gas. In this embodiment, argon gas is used as the carrier gas. The carrier gas is based on the type of film to be formed, such as nitrogen and hydrogen.

The reaction gas storage portion 22 and the carrier gas storage portion 23 are respectively attached to the second gas pipe 90 through independent pipes. One end of the second gas pipe 90 is connected to the film formation chamber 10. The reaction gas stored in the reaction gas storage portion 22 and the carrier gas stored in the carrier gas storage portion 23 are supplied to the film forming chamber 10 through the second gas pipe 90.

In the present embodiment, the reaction gas storage portion 22 and the carrier gas storage portion 23 are connected to the film forming chamber 10 via a common second gas pipe 90, but they may be connected to the film forming chamber 10 via separate gas pipes.

In the middle of the pipe connecting the second gas pipe 90 and the reaction gas storage portion 22, a second adjustment valve 22b for adjusting the flow rate of the reaction gas supplied from the reaction gas storage portion 22 to the film forming chamber 10 is installed. In addition, in the middle of the pipe connecting the second gas pipe 90 and the carrier gas storage portion 23, a third adjustment valve 23b that adjusts the flow rate of the carrier gas supplied from the carrier gas storage portion 23 to the film forming chamber 10 is installed. The second regulating valve 22b and the third regulating valve 23b adjust each valve according to a preset flow The opening.

The flushing gas storage part 24 is a container for storing flushing gas. The flushing gas reservoir 24 is connected to the film forming chamber 10 via a third gas pipe 24a. The flushing gas system is used to remove unreacted gas or reacted gas after the raw material gas is supplied to the film forming chamber 10 and reacts with the substrate 80, or after the reactive gas is supplied to the film forming chamber 10 and reacts with the raw material gas The gas discharged from the film forming chamber 10 and supplied. In this embodiment, nitrogen gas is used as the flushing gas. The flushing gas only needs to be a gas inert to the raw material gas and the reaction gas, and argon gas or the like may also be used.

In the third gas pipe 24a, a fourth adjustment valve 24b for adjusting the flow rate of the flushing gas supplied from the flushing gas storage portion 24 to the film forming chamber 10 is installed. Adjust the opening degree of the fourth regulating valve 24b according to the preset procedure.

The flushing gas of the flushing gas storage portion 24 is also used for returning the film forming chamber 10 to atmospheric pressure after the film forming process is completed. After the film forming process is completed, the fourth regulating valve 24b is opened, and nitrogen gas as a flushing gas is supplied to the film forming chamber 10. When the pressure sensor 50 measures the atmospheric pressure of the film forming chamber 10, the controller 70 controls to close the fourth regulating valve 24b.

The first regulating valve 21b, the second regulating valve 22b, the third regulating valve 23b, and the fourth regulating valve 24b are described and illustrated as variable valves that can change the flow rate, but they may be only open and close. valve.

In this embodiment, the source gas storage section 21 is connected to the film formation chamber 10 via the first gas pipe 21a, and the reaction gas storage section 22 and the carrier gas storage section 23 are connected to the film formation chamber 10 via the second gas pipe 90 to flush The gas storage portion 24 is connected to the film forming chamber 10 via a third gas pipe 24a. The present invention is not limited to such a pipe connection state. For example, the flushing gas storage unit 24 may be connected to the second gas pipe 90.

The high-frequency power source 30 is connected to the first electrode 31 arranged above the inside of the film forming chamber 10. The first electrode 31 is arranged to face the substrate 80 arranged in the film forming chamber 1. Below the substrate 80, a second electrode 32 is arranged. The high-frequency power source 30 and the second electrode 32 are respectively grounded. The high-frequency power supply 30 supplies predetermined power to the first electrode 31, thereby generating plasma between the first electrode 31 and the second electrode 32.

The heater 40 is a device for heating the substrate 80 to improve the reaction activity of the substrate 80 in the film forming process.

The pressure sensor 50 is a measuring device that measures the pressure in the film forming chamber 10. For example, a diaphragm pressure sensor is suitable. In this embodiment, a digital pressure switch for atmospheric pressure confirmation using a stainless steel diaphragm is used, but the pressure sensor 50 may be appropriately selected. For example, other diaphragm pressure sensors such as semiconductor pressure sensors can also be applied. By using a diaphragm pressure sensor, it can operate accurately even if it is installed in a pipe with airflow.

The pressure sensor 50 is installed on the downstream side of the third regulating valve 23b of the second gas pipe 90. Since the pressure sensor 50 is arranged at this position, the pressure sensor 50 will be arranged at a position close to the film forming chamber 10, so that the pressure in the film forming chamber 10 can be accurately measured.

The installation position of the pressure sensor 50 only needs to be installed in the second gas pipe 90, and is not limited to the above-mentioned position. For example, it may be installed between the second adjustment valve 22b and the third adjustment valve 23b. In addition, the second gas pipe 90 may be extended to the upstream side, and the pressure sensor 50 may be installed at the extended position. By installing the pressure sensor 50 in such a position, the design freedom of the film forming apparatus 1 can be increased.

By attaching the pressure sensor 50 to the second gas pipe 90, the raw material gas supplied from the raw gas storage part 21 does not flow into the second gas pipe 90, and the film forming material does not adhere to the pressure sensor 50.

The vacuum pump 60 depressurizes the inside of the film formation chamber 10 via the exhaust pipe 61 and exhausts the gas supplied into the film formation chamber 10. As the vacuum pump 60, a turbo molecular pump or the like is used.

The controller 70 includes a processor, a memory, etc., and a control program of the film forming device 1 is stored in the memory. The controller 70 controls the entire film forming apparatus 1 according to the control program.

Specifically, the controller 70 adjusts the opening degree of the fourth regulating valve 24b based on the pressure value measured by the pressure sensor 50. During the supply of flushing gas, the controller 70 determines that the pressure has reached the atmospheric pressure when the pressure value measured by the pressure sensor 50 becomes greater than a predetermined value. Then, the controller 70 adjusts to close the fourth adjusting valve 24b, and controls to stop the supply of flushing gas.

The controller 70 further controls the opening/closing of the power supply of the first regulating valve 21b, the second regulating valve 22b, the third regulating valve 23b, the high-frequency power supply 30, and the operation of the vacuum pump 60.

Next, the timing of supplying the gas used for film formation and the timing of supplying electric power in the film forming apparatus 1 having such a structure will be described.

The timing of supplying or stopping gas or electricity is shown in the first time chart shown in Figure 2. In the first time chart, ON means gas or electricity is supplied, and OFF means gas or electricity supply is stopped.

The 1 cycle of gas supply/stop and power supply/stop in this embodiment includes: a raw material gas supply step, supplying raw material gas; a first flushing step, after raw material gas is adsorbed on the substrate, flushing gas is supplied to make residue The residual gas in the film forming chamber 1 is discharged; the plasma step is to supply reaction gas to generate plasma; and the second washing step is to supply the washing gas after the raw material gas reacts with the reaction gas so as to remain in the film forming chamber 10 The residual gas is discharged.

When the film forming process starts, the controller 70 controls to open the first regulating valve 21b, the second regulating valve 22b, and the third regulating valve 23b.

By opening the first regulating valve 21b, the supply of the TMA gas as the source gas into the film forming chamber 10 is turned on, and the source gas supply step is started. The controller 70 controls to close the first regulating valve 21b after a predetermined period of time has elapsed, and to close the supply of TMA gas. Subsequently, TMA gas is not supplied until the end of one cycle.

By opening the second regulating valve 22b, the supply of oxygen as a reaction gas into the film forming chamber 10 is turned on. The second regulating valve 22b is opened until the end of one cycle, and oxygen is always supplied to the film forming chamber 10 via the second gas pipe 90 in one cycle.

By opening the third regulating valve 23b, the supply of argon gas as a carrier gas into the film forming chamber 10 is turned on. The third regulating valve 23 b is opened until the end of one cycle, and argon gas is always supplied to the film forming chamber 10 through the second gas pipe 90 in one cycle.

When the source gas supply step ends, the first flushing step starts. During the first flushing step, oxygen and argon are used as flushing gases and are supplied to the film forming chamber 10 through the second gas pipe 90.

When the first rinsing step is completed, the controller 70 turns on the high-frequency power supply 30 to supply power to the first electrode 31, and the plasma step is started. When the predetermined period of time has elapsed, the power supply from the high-frequency power supply 30 to the first electrode 31 is turned off, and the plasma step ends. During the plasma step, oxygen and argon are supplied to the film forming chamber 10 through the second gas pipe 90.

When the plasma step ends, the second rinse step starts. During the second flushing step, oxygen and argon are used as flushing gases and are supplied to the film forming chamber 10 through the second gas pipe 90.

According to the first time chart, oxygen as a reaction gas and argon as a carrier gas are always supplied from the beginning of the film formation process, and in the second gas pipe 90 through which these gases flow, There is gas flowing through. Due to the pressure difference, the gas flowing into the film forming chamber 10 does not flow back to the second gas pipe 90. Therefore, the raw material gas supplied from the raw material gas storage part 21 does not flow into the second gas pipe 90, and it is possible to suppress the adhesion of the film-forming substance to the pressure sensor 50 attached to the second gas pipe 90.

In the first time chart of Fig. 2, oxygen as the reaction gas and argon as the carrier gas always flow through the second gas pipe 90 during the film formation process, but the present invention is not limited to this time chart . For example, if it is the time chart shown in FIG. 3 to FIG. 5, the film forming material will not adhere to the pressure sensor 50 in the same way. Hereinafter, the time chart shown in Fig. 3 is referred to as the second time chart, the time chart shown in Fig. 4 is referred to as the third time chart, and the time chart shown in Fig. 5 is referred to as the fourth time chart.

The second time chart shown in Figure 3 is the time chart as follows, that is, nitrogen is introduced as a flushing gas, and oxygen as a reaction gas and argon as a carrier gas are only turned on during the plasma step, and the raw material In the gas supply step, the supply of argon gas is turned on. The flushing gas system is supplied in the first flushing step and the second flushing step. In the second time chart, it is assumed that the flushing gas storage unit 24 is connected to the gas pipe 90. In the second gas piping 90, argon flows in the raw material gas supply step, both oxygen and argon flow in the plasma step, and nitrogen gas flows in the first flushing step and the second flushing step. Therefore, in the raw material gas supply step or the plasma step, the raw material gas or the plasma active species does not enter the second gas pipe 90, so that the deposition of the film-forming substance on the pressure sensor 50 can be suppressed.

The third time chart shown in Fig. 4 is a time chart as follows, that is, oxygen as a reactive gas is only supplied in the plasma step, and argon as a carrier gas is used from the source gas supply step to the subsequent In the first flushing step, plasma step, and second flushing step, the supply is always on. Use argon as carrier gas as flushing gas. In the second gas piping 90, argon flows in the raw material gas supply step, both oxygen and argon flow in the plasma step, and argon flows in the first and second flushing steps. Therefore, it is possible to suppress the generation of The film-forming substance adheres to the pressure sensor 50 attached to the second gas pipe 90.

The fourth time chart shown in Fig. 5 is a time chart as follows, that is, oxygen as a reaction gas is used from the raw material gas supply step to the subsequent first flushing step, plasma step, and second flushing step, The supply is always turned on, and the supply of argon as the carrier gas is only turned on during the plasma step. In the second gas pipe 90, oxygen flows in the raw material gas supply step, both oxygen and argon flow in the plasma step, and oxygen flows in the first and second flushing steps. Therefore, it is possible to suppress adhesion of the film-forming substance generated during the film-forming process to the pressure sensor 50 attached to the second gas pipe 90.

The timing of flowing the reaction gas and carrier gas is not limited to the timing described above. As long as the timing is controlled, in the raw material gas supply step, two kinds of gases, the reaction gas and the carrier gas, flow into the second gas pipe 90.

Next, the method of performing the film forming process in the film forming apparatus 1 having such a structure will be explained using FIG. 6. The film forming method is controlled and executed by the controller 70. The film formation method executed based on the gas supply control and the power supply control shown in the third time chart will be described as an example.

First, when the operator gives an instruction to start the film forming process by a switch or the like, the vacuum pump 60 is driven, and the film forming process starts.

When the film forming process starts, the pressure in the film forming chamber 10 is reduced by the vacuum pump 60 (step S101). When the inside of the film formation chamber 10 becomes below the predetermined pressure, the controller 70 controls to open the third regulating valve 23b to supply carrier gas into the film formation chamber 10 (step 102), and the controller 70 controls to open the first The regulating valve 21b supplies the TMA gas as the source gas into the film forming chamber 10 (step 103).

The supplied TMA gas will be chemically adsorbed to the surface of the substrate 80 arranged in the film forming chamber 10. The unreacted TMA gas and the reaction product remain in the film forming chamber 10 as residual gas.

When the TMA gas is supplied and a predetermined time has elapsed, the controller 70 closes the first regulating valve 21b, and starts the first flushing step in which the residual gas is discharged from the film formation chamber 10 (step S104). During the first flushing step, argon gas as a carrier gas is supplied as a flushing gas from the carrier gas storage part 23 to the film forming chamber 10.

When the controller 70 determines that the first flushing step has ended based on the pressure value or the elapsed time in the film forming chamber 10, it controls to open the second regulating valve 22b of the reaction gas storage portion 22. When the second regulating valve 22b is opened, oxygen as a reaction gas is supplied to the film forming chamber 10 (step S105).

When oxygen is supplied to the film forming chamber 10, the controller 70 turns on the high-frequency power source 30, and the high-frequency power source 30 supplies power to the first electrode 31 to generate plasma using oxygen in the film forming chamber 10 (step S106). A part of the oxygen becomes oxygen plasma, and the oxygen plasma is combined with the remaining part (aluminum) of TMA in a radical state on the substrate 80 to form a thin film of aluminum oxide (thin film forming step). Residual gases such as water generated by the oxidation of the TMA gas and residual oxygen plasma remain in the film forming chamber 10.

After the film forming step is completed, the controller 70 closes the second regulating valve 22b, and supplies carrier gas (argon gas) as a flushing gas into the film forming chamber 10. By supplying argon gas, the second flushing step in which residual gas, unreacted reaction gas, oxygen radicals, etc. are discharged from the film forming chamber 10 is started (step S107).

When the controller 70 judges that the second flushing step has ended based on the pressure value or the elapsed time in the film forming chamber 10, one cycle of film forming ends. The controller 70 judges whether the deposited film If the predetermined film thickness is less than or equal to the predetermined film thickness (step S108; No), control is performed to open the first regulating valve 21b to supply the TMA gas as a source gas into the film forming chamber 10 (step 103). Afterwards, repeat the cycle of step 103 to step 107 until the specified film thickness is reached.

If the predetermined film thickness has been reached (Step S108; Yes), the pressure recovery of the film forming chamber 10 is started (Step 109). The controller 70 controls to close the third regulating valve 23b. In addition, the controller 70 controls to open the fourth regulating valve 24 b to supply nitrogen gas as a flushing gas to the film forming chamber 10. The pressure in the film forming chamber 10 is measured by the pressure sensor 50. When it is determined by the pressure sensor 50 that the inside of the film formation chamber 10 has returned to the atmospheric pressure, the controller 70 controls to close the fourth regulating valve 24b.

When the fourth regulating valve 24b is closed, the atmosphere in the film formation chamber 10 is opened, and the substrate 80 arranged in the film formation chamber 10 is taken out from the film formation chamber 10, and the film formation process ends.

The pressure sensor 50 functions as a pressure switch capable of opening to atmospheric pressure, and by measuring the pressure in the film forming chamber 10 to be atmospheric pressure, the supply of flushing gas into the film forming chamber 10 is stopped. Even when the pressure sensor 50 is used for this purpose, the film forming material in the film forming chamber 10 can be prevented from adhering to the pressure sensor 50.

The pressure sensor 50 can always measure the pressure inside the film forming chamber 10, and can also be applied to a pressure sensor that turns on the switch only when pressure measurement is required.

According to this embodiment, the pressure sensor 50 for measuring the pressure inside the film forming chamber 10 is arranged on the second gas pipe 90 for supplying gas to the film forming chamber 10 instead of on the exhaust side of the film forming chamber 10. Since the processing gas flows into the second gas pipe 90, it is possible to prevent the film forming material generated in the film forming chamber 10 from adhering to the pressure sensor 50. Therefore, the replacement period of the pressure sensor 50 can be delayed.

According to this embodiment, the reactive gas storage portion 21 and the carrier gas storage portion 22 are connected to One second gas pipe 90 has a pressure sensor 50 attached to the second gas pipe 90. In addition, by appropriately controlling the flow rate of the gas flowing in the second gas pipe 90 by the second regulating valve 22 b and the third regulating valve 23 b, it is possible to suppress adhesion of the film forming material to the pressure sensor 50.

According to this embodiment, in the thin film forming step, since the reactive gas and the carrier gas are always flowed into the gas pipe, the active species in the plasma generated in the thin film forming step will not reach the pressure sensor provided in the gas pipe .

According to this embodiment, in the first flushing step and the second flushing step, a reaction gas or a carrier gas is introduced into the gas pipe to be used as a flushing gas. Therefore, there is no need to prepare a flushing gas separately, and the device becomes compact. In addition, gas materials can be saved.

In the description of the first time chart to the fourth time chart and the description of the film formation processing method in this embodiment, the focus is placed on the timing of supplying the gas used in the film formation process, but the present invention does not Limited to a film forming device that only controls the timing of gas supply. It is also possible to control the flow rate of the gas supplied to the second gas pipe 90 where the pressure sensor 50 is installed. For example, the openings of the second adjustment valve 22b of the reaction gas storage portion 22 connected to the second gas pipe 90 and the third adjustment valve 23b of the carrier gas storage portion 23 may be adjusted separately to control the supply to the second gas pipe 90 The flow of gas. As long as the gas flow rate of the gas flow containing the two types of gas is equal to or higher than the predetermined flow rate, the adhesion of the film-forming material to the pressure sensor 50 can be suppressed.

(Embodiment 2)

In the first embodiment, as a mechanism for generating plasma, parallel plate electrodes are applied, but the present invention is not limited to such electrodes. A gas shower for supplying raw material gas, reaction gas, and carrier gas from above in the film forming chamber 10 can also be provided, and the high-frequency power supply is connected to the gas shower.

Fig. 7 shows a film forming apparatus 1 equipped with a gas shower. The film forming apparatus 1 is provided with film forming The chamber 10, the gas storage part 20, the high frequency power supply 30, the heater 40, the pressure sensor 50, the vacuum pump 60, the controller 70 and the gas shower 100. The structures of the film forming chamber 10, the gas storage unit 20, the high-frequency power supply 30, the heater 40, the pressure sensor 50, the vacuum pump 60, and the controller 70 are the same as those of the first embodiment, so the description is omitted in this embodiment.

The gas shower 100 is a gas supply member that supplies the raw material gas and the processing gas to the substrate 80 arranged in the film forming chamber 10 in a shower shape. The gas shower 100 is a plate-shaped member having an opposing surface 101 facing the substrate 80, and a plurality of ejection holes 102 are formed on the opposing surface 101. In addition, the gas shower 100 is formed of silicon, hydrocarbons, and other components that are resistant to plasma processing.

The gas shower 100 is connected to a high-frequency power source 30, and predetermined power is supplied to the gas shower 90 from the high-frequency power source 30. When the high-frequency power supply 30 supplies power, plasma is generated between the gas shower 100 and the substrate 80.

The case where the gas storage section 20 includes the source gas storage section 21, the reaction gas storage section 22, the carrier gas storage section 23, and the flushing gas storage section 24 is the same as in the first embodiment. However, in Embodiment 1, the reaction gas storage portion 22 and the carrier gas storage portion 23 are connected to the second gas pipe 90, the source gas storage portion 21 is connected to the first gas pipe 21a, and the flushing gas storage portion 24 is connected to the third gas pipe. 24a. In this embodiment, the source gas storage part 21, the reaction gas storage part 22, and the carrier gas storage part 23 are connected to the fourth gas pipe 120 as a common gas pipe. In addition, the source gas, the reaction gas, and the carrier gas are supplied to the gas shower 100 via the fourth gas pipe 120, and each gas is supplied into the film formation chamber 10 from the gas shower 100.

In this embodiment, the raw material gas and the processing gas (reactive gas, carrier gas) are supplied via the gas shower 100. Therefore, during plasma processing, the plasma generated in the film forming chamber 10 can be prevented from intruding into the pressure sensor. Inside the fourth gas pipe 120 of the device 50. Therefore, the pressure sensor 50 provided in the fourth gas pipe 120 is not exposed to the plasma, thereby reliably preventing the film from being deposited on the pressure sensor. 测器50.

Connect the raw material gas storage section 21 to the downstream side (the film formation chamber 10 side) in the fourth gas pipe 120, connect the carrier gas storage section 23 and the pressure sensor 50 to the upstream side, and in the raw gas supply step, The carrier gas and the raw material gas are simultaneously introduced into the film forming chamber 10, thereby suppressing the raw material gas from being adsorbed on the pressure sensor 50. Alternatively, the source gas storage section 21 may be connected to a gas piping of a system different from that of the fourth gas piping 120.

The embodiments of the present invention have been described above, but the present invention is not limited to the embodiments described so far, and includes adding appropriate changes.

In the first and second embodiments, the case where an oxide film is formed using an oxidizing gas (oxygen) has been described as an example, but the present invention is not limited to such an oxidizing gas. For example, it can also be applied to a film forming apparatus that uses a nitriding gas to form a nitride film.

In the first and second embodiments, the PE-ALD apparatus was used to describe the film forming apparatus, but as long as it is a film forming apparatus that performs a gaseous film forming process, it is not limited to a PE-ALD apparatus. For example, the film forming apparatus 1 of the present invention can also be applied to a CVD apparatus.

In the first and second embodiments, the substrate 80 is used as an example of the work, but the object of film formation using the film forming apparatus of the present invention is not limited to the substrate 80. For example, it can be used for various workpieces such as fuel cells, organic EL, solar cells, displays, LEDs, and piezoelectric elements.

[Industrial availability]

The present invention can be used in a film forming apparatus equipped with a pressure sensor for measuring the pressure inside the film forming chamber.

1‧‧‧Film forming device

10‧‧‧Film forming room

20‧‧‧Gas Storage Department

21‧‧‧Raw gas storage department

21a‧‧‧First gas piping

21b‧‧‧The first adjusting valve

22‧‧‧Reactive gas storage

22b‧‧‧Second regulating valve

23‧‧‧Carrier Gas Storage

23b‧‧‧The third adjusting valve

24‧‧‧Flushing gas storage

24a‧‧‧3rd gas piping

24b‧‧‧4th adjusting valve

30‧‧‧High frequency power supply

31‧‧‧First electrode

32‧‧‧Second electrode

40‧‧‧Heater

50‧‧‧Pressure sensor

60‧‧‧Vacuum pump

61‧‧‧Exhaust pipe

70‧‧‧Controller

80‧‧‧Substrate

90‧‧‧Second gas piping

Claims (10)

A film forming apparatus includes: a film forming chamber inside which performs film forming processing on a workpiece; a raw material gas supply part used for the above film forming process and supplies raw material gas containing film forming components to the film forming chamber; A gas piping for use in the film formation process to supply a process gas different from the raw material gas to the film formation chamber from a process gas storage section storing the process gas; a pressure sensor, which is installed in the gas piping, Measuring the pressure inside the film forming chamber; and a control unit that controls to flow the source gas from the process gas storage part into the film forming chamber while the source gas is supplied from the source gas supply part to the film forming chamber The gas piping is supplied to the film forming chamber. The film forming apparatus according to claim 1, wherein the gas piping is provided with an adjustment valve that adjusts the flow rate of the processing gas supplied from the processing gas storage section to the film forming chamber, and the control section performs It is controlled to open the adjustment valve while the raw material gas is supplied from the raw material gas supply part to the film forming chamber. The film forming apparatus according to claim 2, wherein the pressure sensor is installed on the downstream side of the regulating valve of the gas piping. The film forming apparatus according to claim 1, wherein the processing gas is a reaction gas or a carrier gas that reacts with the raw material gas. The film forming apparatus according to claim 1, wherein the pressure sensor is a diaphragm pressure sensor. The film forming apparatus according to claim 1, further comprising a purge gas supply part for supplying purge gas to the film forming chamber, and the pressure sensor is a pressure sensor for measuring whether the pressure in the film forming chamber is atmospheric pressure The control unit controls to stop the supply of the flushing gas supplied from the flushing gas supply unit to the filming chamber when the pressure in the film forming chamber is measured by the pressure sensor to be atmospheric pressure. The film forming apparatus according to claim 1, which further includes a gas shower connected to the downstream end of the gas pipe, arranged opposite to the workpiece in the film forming chamber, and having a gas shower formed on the A plurality of spray holes on the opposing surface of the workpiece, and the gas shower supplies the processing gas supplied from the gas piping to the surface of the workpiece in a shower shape from the spray holes. A film forming method includes: a raw material gas supply step, which supplies a raw material gas containing film forming components to a film forming chamber, so that the raw material gas is adsorbed on the surface of a workpiece; a first flushing step, which supplies a flushing gas to the surface The residual gas in the film forming chamber is flushed; the thin film forming step, after the first flushing step, the reaction gas and the carrier gas that react with the raw material gas are fed into the gas piping equipped with a pressure sensor and supplied To the film forming chamber, the plasma of the reaction gas is generated, and the raw material gas adsorbed on the surface of the workpiece reacts with the plasma of the reaction gas to form a thin film on the surface of the workpiece, and the pressure sensor forms the film Measuring the pressure in the chamber; and a second flushing step of supplying the flushing gas after the thin film forming step, flushing the residual gas remaining in the film forming chamber, and in the raw gas supply step, making the reaction gas Or, the carrier gas flows into the gas pipe and is supplied to the film forming chamber. The film forming method according to claim 8, wherein in the thin film forming step, the reaction gas and the carrier gas are always flowed into the gas pipe. The film forming method according to claim 8, wherein in the first flushing step and the second flushing step, the reaction gas or the carrier gas is introduced into the gas pipe and supplied as the flushing gas to the film formation room.

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