JP2012023138A - Substrate processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a situation in which it takes a lot of time until completion of exhaustion by immediately recognizing the fact that exhaustion of gas is not started correctly while avoiding mixture of a plurality of kinds of processing gas.SOLUTION: The substrate processing apparatus comprises: a processing chamber in which a substrate is contained; a gas supply system which supplies a plurality of kinds of processing gas mixture of which must be avoided into the processing chamber via piping, i.e. the passage of the processing gas; and a gas exhaust system which exhausts gas in the processing chamber and the piping. The substrate processing apparatus is further provided with a control unit which controls a display to display the state of gas stagnating in the piping in at least three stages of gas stagnation state, under exhaustion state, and exhaustion completion state.

Description

  The present invention relates to a substrate processing apparatus for processing a substrate.

  A wide variety of gases are used in the semiconductor device manufacturing process. Therefore, it should be noted that there is a risk of mixed fire depending on the type of gas to be combined, such as combustible gas and combustion-supporting gas. For this reason, in a substrate processing apparatus that uses a plurality of types of processing gases, it is common practice to avoid ingestion of the plurality of types of processing gases by the exhaust sequence control described below. In other words, after supplying the processing gas into the processing chamber containing the substrate and starting exhausting of the gas staying in the processing chamber and the piping connected to the processing chamber, the exhaust operation is continued until a certain time has elapsed from the start of the exhaust. And do it. When there is no gas remaining in the processing chamber and piping after a certain period of time has passed, information indicating that the exhaust of the gas has been completed can be displayed, and supply of another type of processing gas into the processing chamber can be started. To. Such an exhaust sequence is repeated for various processing gases.

  In the substrate processing apparatus that performs the exhaust sequence control described above, exhaust of the staying gas from the processing chamber and the piping is started when the switching of the valve open / close state in the piping is correctly performed. However, the switching of the valve open / close state may be erroneously performed due to a work mistake, for example, when an operator performs the manual operation. In that case, the operator rarely notices an error immediately after the operation, and often notices the error only when the information on the completion of the exhaust is not displayed even after a certain time has passed since the operation. Therefore, if the switching of the valve open / close state is mistakenly performed, it takes a long time to complete the exhaust sequence because the worker is late to notice that.

  The present invention makes it possible to recognize immediately when gas exhaust is not started correctly while avoiding the mixing of plural types of processing gases, thereby suppressing the time required for exhaust completion. An object of the present invention is to provide a substrate processing apparatus that can be used.

  According to one aspect of the present invention, a processing chamber that accommodates a substrate, a gas supply system that supplies a plurality of types of processing gases to be prevented from being mixed into the processing chamber through piping that is a flow path of the processing gas, A gas exhaust system for exhausting the gas in the processing chamber and the pipe, and the state of the gas staying in the pipe is displayed on the display unit in at least three stages: a gas remaining state, an exhausting state, and an exhausted state There is provided a substrate processing apparatus characterized in that a control unit is provided.

  According to the substrate processing apparatus of the present invention, if gas exhaust is not started correctly, it can be recognized immediately. Therefore, it can be suppressed that much time is required until exhaust is completed.

It is a schematic block diagram of the substrate processing apparatus concerning one Embodiment of this invention. It is a schematic block diagram of the processing furnace with which the substrate processing apparatus concerning one Embodiment of this invention is provided, (a) is a longitudinal cross-sectional schematic diagram of a processing furnace, (b) is a figure which shows the cross-sectional schematic diagram of a processing furnace, respectively. It is. It is a flowchart which shows the procedure of the substrate processing process concerning one Embodiment of this invention. It is a chart figure showing a process sequence of a substrate processing process concerning one embodiment of the present invention. It is a schematic diagram which shows the ladder program outline | summary of the exhaust sequence control by the conventional structure used as the reference example of this invention. It is a schematic diagram which shows one specific example of the exhaust sequence control by the conventional structure used as the reference example of this invention, (a) is a figure which shows the supply state of 1st process gas, (b) is 1st process gas by a normal setting. FIG. 6C is a diagram showing an exhaust state of the first processing gas due to an abnormal setting. It is a schematic diagram which shows the ladder program outline | summary of the exhaust sequence control concerning one Embodiment of this invention. It is a schematic diagram which shows one specific example of the exhaust sequence control concerning one Embodiment of this invention, (a) is a figure which shows the supply state of 1st process gas, (b) is exhaust of the 1st process gas by a normal setting. The figure which shows a state, (c) is a figure which shows the exhaustion state of the 1st process gas by abnormal setting.

  Embodiments of the present invention will be described below with reference to the drawings.

(1) Configuration of Substrate Processing Apparatus First, a configuration example of a substrate processing apparatus 101 according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic configuration diagram of a substrate processing apparatus according to an embodiment of the present invention.

  As shown in FIG. 1, the substrate processing apparatus 101 according to the present embodiment includes a housing 111. In order to transport a wafer (substrate) 200 made of silicon or the like into and out of the casing 111, a cassette 110 as a wafer carrier (substrate storage container) that stores a plurality of wafers 200 is used. A cassette stage (substrate storage container delivery table) 114 is provided in front of the housing 111 (on the right side in the drawing). The cassette 110 is placed on the cassette stage 114 by an in-process transfer device (not shown), and is carried out of the casing 111 from the cassette stage 114.

  The cassette 110 is placed on the cassette stage 114 so that the wafer 200 in the cassette 110 is in a vertical posture and the wafer loading / unloading port of the cassette 110 faces upward by the in-process transfer device. The cassette stage 114 rotates the cassette 110 90 degrees in the vertical direction toward the rear of the casing 111 to bring the wafer 200 in the cassette 110 into a horizontal posture, and the wafer loading / unloading port of the cassette 110 is placed behind the casing 111. It is configured to be able to face.

  A cassette shelf (substrate storage container mounting shelf) 105 is installed at a substantially central portion in the front-rear direction in the housing 111. The cassette shelf 105 is configured to store a plurality of cassettes 110 in a plurality of rows and a plurality of rows. The cassette shelf 105 is provided with a transfer shelf 123 in which a cassette 110 to be transferred by a wafer transfer mechanism 125 described later is stored. Further, a preliminary cassette shelf 107 is provided above the cassette stage 114, and is configured to store the cassette 110 in a preliminary manner.

A cassette transfer device (substrate container transfer device) 118 is provided between the cassette stage 114 and the cassette shelf 105. The cassette transport device 118 includes a cassette elevator (substrate storage container lifting mechanism) 118a that can be moved up and down while holding the cassette 110, and a cassette transport mechanism (substrate storage container transport mechanism) as a transport mechanism that can move horizontally while holding the cassette 110. 118b. By the cooperative operation of the cassette elevator 118a and the cassette transport mechanism 118b, the cassette stage 114, cassette shelf 105,
The cassette 110 is transported between the spare cassette shelf 107 and the transfer shelf 123.

  A wafer transfer mechanism (substrate transfer mechanism) 125 is provided behind the cassette shelf 105. The wafer transfer mechanism 125 includes a wafer transfer device (substrate transfer device) 125a that can rotate or linearly move the wafer 200 in the horizontal direction, and a wafer transfer device elevator (substrate transfer device) that moves the wafer transfer device 125a up and down. Elevating mechanism) 125b. The wafer transfer device 125a includes a tweezer (substrate transfer jig) 125c that holds the wafer 200 in a horizontal posture. The wafer 200 is picked up from the cassette 110 on the transfer shelf 123 by the cooperative operation of the wafer transfer device 125a and the wafer transfer device elevator 125b, and loaded into the boat (substrate support member) 217 described later (charging). Or the wafer 200 is unloaded (discharged) from the boat 217 and stored in the cassette 110 on the transfer shelf 123.

  A processing furnace 202 is provided above the rear portion of the casing 111. An opening is provided at the lower end of the processing furnace 202, and the opening is configured to be opened and closed by a furnace port shutter (furnace port opening / closing mechanism) 147. The configuration of the processing furnace 202 will be described later.

  Below the processing furnace 202, a boat elevator (substrate support member lifting mechanism) 115 is provided as a lifting mechanism that lifts and lowers the boat 217 and transports the boat 217 into and out of the processing furnace 202. The elevator 128 of the boat elevator 115 is provided with an arm 128 as a connecting tool. On the arm 128, a seal cap 219 is provided in a horizontal posture as a lid that supports the boat 217 vertically and that hermetically closes the lower end of the processing furnace 202 when the boat 217 is raised by the boat elevator 115. ing.

  The boat 217 includes a plurality of holding members, and a plurality of (for example, about 50 to 150) wafers 200 are aligned in the vertical direction in a horizontal posture and in a state where the centers thereof are aligned in multiple stages. Configured to hold. The detailed configuration of the boat 217 will be described later.

  Above the cassette shelf 105, a clean unit 134a having a supply fan and a dustproof filter is provided. The clean unit 134a is configured to circulate clean air, which is a cleaned atmosphere, inside the casing 111.

  In addition, a clean unit (not shown) provided with a supply fan and a dustproof filter so as to supply clean air to the left end portion of the housing 111 opposite to the wafer transfer device elevator 125b and the boat elevator 115 side. Is installed. Clean air blown out from the clean unit (not shown) is configured to be sucked into an exhaust device (not shown) and exhausted to the outside of the casing 111 after circulating around the wafer transfer device 125a and the boat 217. ing.

(2) Operation of Substrate Processing Apparatus Next, the operation of the substrate processing apparatus 101 according to the present embodiment will be described.

  First, the cassette 110 is placed on the cassette stage 114 by an in-process transfer device (not shown) so that the wafer 200 is in a vertical posture and the wafer loading / unloading port of the cassette 110 faces upward. Thereafter, the cassette 110 is rotated 90 ° in the vertical direction toward the rear of the casing 111 by the cassette stage 114. As a result, the wafer 200 in the cassette 110 assumes a horizontal posture, and the wafer loading / unloading port of the cassette 110 faces rearward in the housing 111.

  The cassette 110 is automatically transported to the designated shelf position of the cassette shelf 105 or the spare cassette shelf 107 by the cassette transporting device 118, delivered, temporarily stored, and then stored in the cassette shelf 105 or the spare cassette shelf. The sample is transferred from 107 to the transfer shelf 123 or directly transferred to the transfer shelf 123.

  When the cassette 110 is transferred to the transfer shelf 123, the wafer 200 is picked up from the cassette 110 through the wafer loading / unloading port by the tweezer 125c of the wafer transfer device 125a, and the wafer transfer device 125a and the wafer transfer device elevator 125b are picked up. Are loaded (charged) into the boat 217 behind the transfer chamber 124. The wafer transfer mechanism 125 that has transferred the wafer 200 to the boat 217 returns to the cassette 110 and loads the next wafer 200 into the boat 217.

  When a predetermined number of wafers 200 are loaded into the boat 217, the lower end of the processing furnace 202 closed by the furnace port shutter 147 is opened by the furnace port shutter 147. Subsequently, when the seal cap 219 is raised by the boat elevator 115, the boat 217 holding the wafer 200 group is loaded into the processing furnace 202. After loading, arbitrary processing is performed on the wafer 200 in the processing furnace 202. Such processing will be described later. After the processing, the wafer 200 and the cassette 110 are discharged to the outside of the casing 111 by a procedure reverse to the above procedure.

(3) Configuration of Processing Furnace Next, the configuration of the processing furnace 202 according to an embodiment of the present invention will be described with reference to the drawings. 2A and 2B are schematic configuration diagrams of a processing furnace provided in a substrate processing apparatus according to an embodiment of the present invention. FIG. 2A is a schematic longitudinal sectional view of the processing furnace, and FIG. The cross-sectional schematic of a processing furnace is shown, respectively.

(Processing room)
A processing furnace 202 according to an embodiment of the present invention includes a reaction tube 203 that constitutes a reaction vessel (processing vessel). The reaction tube 203 is made of a heat-resistant non-metallic material such as quartz (SiO ₂ ) or silicon carbide (SiC), and has a cylindrical shape with its upper end closed and its lower end open. The lower end of the reaction tube 203 is configured to be hermetically sealed by a seal cap 219 made of a metal such as stainless steel and formed in a disk shape when the above-described boat elevator 115 is raised. A sealing member 220 such as an O-ring that hermetically seals the inside of the processing chamber 201 is provided between the lower end portion of the reaction tube 203 and the seal cap 219.

  Inside the reaction tube 203, a processing chamber 201 for accommodating a wafer 200 as a substrate is formed. A boat 217 as a substrate holder is inserted into the processing chamber 201 from below. The inner diameter of the reaction tube 203 is configured to be larger than the maximum outer shape of the boat 217 loaded with the wafers 200.

The boat 217 is formed of a heat-resistant material such as quartz or silicon carbide, and holds a plurality of (for example, 75 to 100) wafers 200 in multiple stages with a predetermined gap (substrate pitch interval) in a substantially horizontal state. It is configured as follows. The boat 217 is mounted on a heat insulating cap 218 that blocks heat conduction from the boat 217. The heat insulating cap 218 is formed of a heat resistant material such as quartz or silicon carbide, and is supported from below by a rotating shaft 255. The rotation shaft 255 is provided so as to penetrate the center portion of the seal cap 219 while maintaining airtightness in the processing chamber 201. A rotation mechanism 267 that rotates the rotation shaft 255 is provided below the seal cap 219. The rotation mechanism 267 rotates the rotation shaft 255 so that the boat 217 loaded with the plurality of wafers 200 can be rotated while maintaining the airtightness in the processing chamber 201.

  A heater 207 as a heating means (heating mechanism) is provided on the outer periphery of the reaction tube 203 concentrically with the reaction tube 203. The heater 207 has a cylindrical shape and is vertically installed by being supported by a heater base (not shown) as a holding plate.

  A temperature sensor 263 is installed in the reaction tube 203 as a temperature detector. The temperature sensor 263 is configured in an L shape having a vertical portion and a horizontal portion. The vertical portion of the temperature sensor 263 is disposed in the vertical direction along the inner wall of the reaction tube 203. By adjusting the heating temperature of the heater 207 based on the temperature information detected by the temperature sensor 263, the processing chamber 201 is configured to have a desired temperature distribution.

(Vaporized gas supply system)
The reaction tube 203 is provided with a vaporized gas nozzle 233a as a vaporized gas introduction part. The vaporized gas nozzle 233a is configured in an L shape having a vertical portion and a horizontal portion. The vertical portion of the vaporized gas nozzle 233a is disposed in the vertical direction along the inner wall of the reaction tube 203. A plurality of vaporized gas supply holes 248a are provided in the vertical direction on the side surface of the vaporized gas nozzle 233a. The opening diameter of the vaporized gas supply hole 248a may be the same from the lower part to the upper part, or may be gradually increased from the lower part to the upper part. The horizontal portion of the vaporized gas nozzle 233 a is provided so as to penetrate the side wall of the reaction tube 203.

  The downstream end of the vaporized gas supply pipe 240a that supplies vaporized gas into the processing chamber 201 is connected to the horizontal end (upstream side) of the vaporized gas nozzle 233a protruding from the side wall of the reaction tube 203. The vaporized gas supply pipe 240a is provided with an open / close valve 543 that is an open / close valve, a vaporizer (vaporizer) 500, a mass flow controller (MFC) 241a that is a flow controller, and an open / close valve 243a that is an open / close valve in order from the upstream side. It has been. When the vaporizer 260 receives a liquid raw material supplied from a liquid raw material supply source (not shown) via the opening / closing valve 543, the vaporizer 260 is heated to a predetermined temperature and vaporized to generate a vaporized gas (raw material gas). It is configured. The mass flow controller (MFC) 241a is configured to monitor the flow rate of the vaporized gas and enable feedback control of the vaporization amount in the vaporizer 500. Further, by opening the on-off valve 243a, the vaporized gas generated in the vaporizer 500 is supplied into the processing chamber 201.

The vaporized gas supply system which is one of the gas supply systems according to the present embodiment is mainly configured by the vaporized gas nozzle 233a, the vaporized gas supply pipe 240a, the vaporizer 500, the mass flow controller (MFC) 241a, and the open / close valve 243a. Yes. For example, a silicon source gas, that is, a gas containing silicon (Si) (silicon-containing gas) is supplied into the processing chamber 201 by the vaporized gas supply system. As the silicon-containing gas, for example, hexachlorodisilane (Si ₂ Cl ₆ , abbreviation: HCD) gas can be used. The silicon source gas may be any of solid, liquid, and gas at normal temperature and pressure, but will be described as liquid here. If the silicon source gas is a gas at normal temperature and pressure, the vaporizer 500 need not be provided.

(Reactive gas supply system)
The reaction tube 203 is provided with a reaction gas nozzle 233b as a reaction gas introduction part. The reactive gas nozzle 233b is configured in an L shape having a vertical portion and a horizontal portion. The vertical portion of the reaction gas nozzle 233b is arranged in the vertical direction along the inner wall of the reaction tube 203. A plurality of reactive gas supply holes 248b are provided in the vertical direction on the side surface of the vertical portion of the reactive gas nozzle 233b. The opening diameter of the reactive gas supply hole 248b may be the same from the lower part to the upper part, or may be gradually increased from the lower part to the upper part. The horizontal portion of the reaction gas nozzle 233b is provided so as to penetrate the side wall of the reaction tube 203.

  The downstream end of the reaction gas supply pipe 240b that supplies the reaction gas into the processing chamber 201 is connected to the horizontal end (upstream side) of the reaction gas nozzle 233b protruding from the side wall of the reaction tube 203. On the upstream side of the reaction gas supply pipe 240b, a downstream end of a first process gas supply pipe (hereinafter simply referred to as “first supply pipe”) 240c and a second process gas supply pipe (hereinafter simply referred to as “first gas supply pipe”). 2) "The downstream end of 240d is connected. That is, the upstream side of the reactive gas supply pipe 240b is connected to both the downstream end of the first supply pipe 240c and the downstream end of the second supply pipe 240d.

  The first supply pipe 240c is provided with an open / close valve 243c as an open / close valve, a mass flow controller (MFC) 241c as a flow controller, and an open / close valve 244c as an open / close valve in order from the upstream side. A first processing gas supply source (not shown) is connected to the upstream end of the first supply pipe 240c. By opening the opening / closing valve 243c and the opening / closing valve 244c, the first processing gas from the first processing gas supply source is supplied. The first supply pipe 240c and the reaction gas supply pipe 240b are configured to be supplied into the processing chamber 201. The supply flow rate of the first processing gas into the processing chamber 201 is configured to be controllable by a mass flow controller (MFC) 241c.

A reaction gas nozzle 233b, a reaction gas supply pipe 240b, a first supply pipe 240c, an on-off valve 243c, a mass flow controller (MFC) 241c, and an on-off valve 244c are used as a first gas supply system according to this embodiment. A processing gas supply system is configured. For example, a gas containing nitrogen (N) (nitrogen-containing gas) is supplied into the processing chamber 201 as the first processing gas by the first processing gas supply system. As the nitrogen-containing gas, for example, ammonia (NH ₃ ) gas can be used.

  The second supply pipe 240d is provided with an open / close valve 243d as an open / close valve, a mass flow controller (MFC) 241d as a flow rate controller, and an open / close valve 244d as an open / close valve in order from the upstream side. A second processing gas supply source (not shown) is connected to the upstream end of the second supply pipe 240d. By opening the opening / closing valve 243d and the opening / closing valve 244d, the second processing gas from the second processing gas supply source is supplied. The second supply pipe 240d and the reaction gas supply pipe 240b are configured to be supplied into the processing chamber 201. Note that the supply flow rate of the second processing gas into the processing chamber 201 is configured to be controllable by a mass flow controller (MFC) 241d.

Mainly, the reactive gas nozzle 233b, the reactive gas supply pipe 240b, the second supply pipe 240d, the open / close valve 243d, the mass flow controller (MFC) 241d, and the open / close valve 244d is a second gas supply system according to this embodiment. A processing gas supply system is configured. For example, a gas containing oxygen (O) (oxygen-containing gas) is supplied into the processing chamber 201 as the second processing gas by the second processing gas supply system. As the oxygen-containing gas, for example, oxygen (O ₂ ) gas can be used.

(Carrier gas supply system)
The downstream end of the carrier gas supply pipe 240e is connected between the mass flow controller (MFC) 241c and the on-off valve 244c in the first supply pipe 240c. The downstream end of the carrier gas supply pipe 240f is connected between the mass flow controller (MFC) 241d and the opening / closing valve 244d in the second supply pipe 240d. The upstream ends of the carrier gas supply pipe 240e and the carrier gas supply pipe 240f all have an inert gas such as helium (He), neon (Ne), argon (Ar), nitrogen (N ₂ ) or the like as a carrier gas. It is connected to a carrier gas supply source (not shown) for supply.

  The carrier gas supply pipe 240e is provided with an open / close valve 243e which is an open / close valve. By opening the on-off valve 243e, the carrier gas is supplied into the first supply pipe 240c, and the mixed gas of the first processing gas and the carrier gas passes through the first supply pipe 240c and the reaction gas supply pipe 240b in the processing chamber 201. It is comprised so that it may be supplied to.

  The carrier gas supply pipe 240f is provided with an open / close valve 243f which is an open / close valve. By opening the on-off valve 243f, the carrier gas is supplied into the second supply pipe 240d, and the mixed gas of the second processing gas and the carrier gas passes through the second supply pipe 240d and the reaction gas supply pipe 240b into the processing chamber 201. It is comprised so that it may be supplied to.

  The carrier gas supply system according to this embodiment is mainly configured by the carrier gas supply pipes 240e and 240f, the on-off valves 243e and 243f, and a carrier gas supply source (not shown).

(Purge gas supply pipe)
The downstream end of the first purge gas pipe 240g is connected to the vaporized gas supply pipe 240a on the downstream side of the open / close valve 243a. The first purge gas pipe 240g is provided with a purge gas supply source (not shown) for supplying an inert gas such as N ₂ gas, a mass flow controller (MFC) 241g, and an opening / closing valve 243g, which is an opening / closing valve, in order from the upstream side. By opening the opening / closing valve 243g, the purge gas is supplied into the processing chamber 201, and the discharge of the vaporized gas from the vaporized gas supply pipe 240a and the processing chamber 201 is promoted.

Similarly, the downstream end of the second purge gas pipe 240h is connected to the reaction gas supply pipe 240b. The connection location is located downstream of the opening / closing valve 244c in the first supply pipe 240c and the opening / closing valve 244 in the second supply pipe 240d. The second purge gas pipe 240h is provided with a purge gas supply source (not shown) for supplying an inert gas such as N ₂ gas, a mass flow controller (MFC) 241h, and an open / close valve 243h in order from the upstream side. The purge gas is supplied into the processing chamber 201 by opening the opening / closing valve 243h. More specifically, by opening the on-off valves 243h and 244c and closing the on-off valves 243c, 243e and 244d, supply of the purge gas into the processing chamber 201 is started, and the first supply pipe 240c and the reaction gas supply pipe 240b are started. It is possible to prompt the discharge of the first processing gas from the inside of the processing chamber 201. Further, by opening the on-off valves 243h, 244d and closing the on-off valves 243d, 243f, 244c, supply of the purge gas into the processing chamber 201 is started, and the inside of the second supply pipe 240d, the reaction gas supply pipe 240b, It becomes possible to promote the discharge of the second processing gas from the processing chamber 201.

  The purge gas supply system according to this embodiment is mainly configured by the first purge gas pipe 240g, the second purge gas pipe 240h, the open / close valves 243g and 243h, and a purge gas supply source (not shown).

(Gas exhaust system)
An exhaust pipe 231 serving as an exhaust system for exhausting the atmosphere in the processing chamber 201 is connected to the side wall of the reaction tube 203. The exhaust pipe 231 is provided with a pressure sensor 245 as a pressure detector, an APC (Auto Pressure Controller) valve 246 as a pressure regulator, and a vacuum pump 247 as a vacuum exhaust device in order from the upstream side. By adjusting the opening degree of the opening / closing valve of the APC valve 246 while operating the vacuum pump 247, the inside of the processing chamber 201 is set to a desired pressure, and the reaction gas is supplied into the processing chamber 201 and the vaporized gas supply pipe 240a connected thereto. It is configured so that the staying gas can be exhausted from the supply pipe 240b, the first supply pipe 240c, the second supply pipe 240d, and the like.

  The gas exhaust system according to the present embodiment is mainly configured by the exhaust pipe 231, the pressure sensor 245, the APC valve 246, and the vacuum pump 247.

(controller)
The controller 280 serving as a control unit (control means) includes a heater 207, an APC valve 246, a vacuum pump 247, a rotation mechanism 267, a boat elevator 215, open / close valves 243a, 243c, 243d, 243e, 243f, 243g, 243h, 244c, and 244d. 543, and mass flow controllers 241a, 241c, 241d, 241g, 241h, and the like. The controller 280 adjusts the temperature of the heater 207, opens and closes the APC valve 246 and adjusts the pressure, starts and stops the vacuum pump 247, adjusts the rotation speed of the rotating mechanism 267, moves the boat elevator 215 up and down, and opens and closes the valves 243a, 243c, Controls such as opening / closing operations of 243d, 243e, 243f, 243g, 243h, 244c, 244d, 543, flow rate adjustment of the mass flow controllers 241a, 241c, 241d, 241g, 241h are performed. The controller 280 has a timer function and an information storage function in addition to the various control functions described above.

(Gas pattern panel)
The controller 280 is connected to a gas pattern panel 281 that is a display unit (display means). The gas pattern panel 281 is provided with an LED (Light Emitting Diode) display, which is a display portion for displaying information about a gas exhaust state to be described later. The LED display is individually provided for each of the vaporized gas supply system, the first processing gas supply system, the second processing gas supply system, and the processing chamber 201. However, it is not necessarily required to be separate, and some or all of them may be provided.

(4) Substrate Processing Step Next, a substrate processing step as an embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a flowchart showing the procedure of the substrate processing step as one embodiment of the present invention. FIG. 4 is a chart showing a process sequence in the substrate processing step as one embodiment of the present invention.

The substrate processing step described in this embodiment is a method of forming a film on the surface of the wafer 200 by using an ALD method which is one of CVD (Chemical Vapor Deposition) methods. Implemented as a process. Here, HCD gas, which is a silicon-containing gas, is used as the vaporization gas, NH ₃ gas, which is a nitrogen-containing gas, is used as the first processing gas, and oxygen-containing gas is used as the second processing gas, among the reaction gases. An example in which a silicon oxynitride film (SiON film) is formed as an insulating film on the wafer 200 using O ₂ gas will be described. In the following description, the operation of each part constituting the substrate processing apparatus 101 is controlled by the controller 280.

(Substrate loading process)
First, a plurality of wafers 200 are loaded into the boat 217 (wafer charge). Then, the boat 217 holding the plurality of wafers 200 is lifted by the boat elevator 115 and loaded into the processing chamber 201 (boat loading). In this state, the seal cap 219 seals the lower end of the reaction tube 203 via the O-ring 220. In the substrate carry-in step (S10), it is preferable that the opening / closing valve 243g and the opening / closing valve 243h are opened and the purge gas is continuously supplied into the processing chamber 201.

(Decompression and temperature rise process)
Subsequently, the opening / closing valve 241g and the opening / closing valve 241h are closed, and the inside of the processing chamber 201 is exhausted (pressure adjusted) by the vacuum pump 247 so that the inside of the processing chamber 201 has a desired pressure (degree of vacuum). At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and the opening degree of the APC valve 246 is feedback-controlled based on the measured pressure. Further, heating (temperature adjustment) is performed by the heater 207 so that the inside of the processing chamber 201 has a desired temperature. At this time, feedback control of the energization state to the heater 207 is performed based on the temperature information detected by the temperature sensor so that the inside of the processing chamber 201 has a desired temperature distribution. Then, the boat 217 is rotated by the rotation mechanism 267 to rotate the wafer 200.

(Film formation process)
Subsequently, a film forming process is performed. In the film forming process, an HCD supply process for supplying HCD gas onto the wafer 200 (step 11), a residual gas removal process for removing residual gas of the HCD gas (step 12), and an NH ₃ gas is supplied onto the wafer 200. a NH ₃ supply step of (step 13), and residual gas removing step of removing the residual gas of the NH ₃ gas (step 14), and supplies _{O 2} gas on the wafer 200 _{O 2} supply process (step 15), The residual gas removing step (step 16) for removing the residual gas of O ₂ gas is defined as one cycle, and this cycle is repeated a predetermined number of times.

(HCD supply process (step 11))
In the HCD supply step (step 11), the open / close valves 543 and 243a of the vaporized gas supply pipe 240a are opened, and the HCD gas is caused to flow into the vaporized gas supply pipe 240a through the vaporizer 500. The flow rate of the HCD gas flowing through the vaporized gas supply pipe 240a is adjusted by the mass flow controller 241a. The HCD gas whose flow rate has been adjusted is exhausted from the gas exhaust pipe 231 while being supplied into the processing chamber 201 from the vaporized gas supply hole 248a of the vaporized gas nozzle 233a. At this time, the opening / closing valve 243g is simultaneously opened, and an inert gas such as N ₂ gas is allowed to flow into the first purge gas pipe 240g. The flow rate of the N ₂ gas flowing through the first purge gas pipe 240g is adjusted by the mass flow controller 241g. The N ₂ gas whose flow rate has been adjusted is exhausted from the gas exhaust pipe 231 while being supplied into the processing chamber 201 together with the HCD gas.

At this time, the APC valve 246 is appropriately adjusted so that the pressure in the processing chamber 201 is, for example, in the range of 10 to 1000 Pa. The supply flow rate of the HCD gas controlled by the mass flow controller 241a is, for example, a flow rate in the range of 100 to 1000 sccm. The supply flow rate of N ₂ gas controlled by the mass flow controller 241g is, for example, a flow rate in the range of 200 to 1000 sccm. The time for exposing the HCD gas to the wafer 200, that is, the gas supply time (irradiation time) is, for example, a time within the range of 1 to 120 seconds. At this time, the temperature of the heater 207 is set to a temperature at which a CVD reaction occurs in the processing chamber 201, that is, a temperature at which the temperature of the wafer 200 becomes a temperature in the range of 300 to 650 ° C., for example. When the temperature of the wafer 200 is less than 300 ° C., it becomes difficult for HCD to be adsorbed on the wafer 200. Further, when the temperature of the wafer 200 exceeds 650 ° C., the CVD reaction becomes strong, and the uniformity tends to deteriorate. Therefore, the temperature of the wafer 200 is preferably set to a temperature within the range of 300 to 650 ° C.

By supplying the HCD gas, a first layer containing silicon is formed on the base film on the surface of the wafer 200. That is, a silicon layer (Si layer) as a silicon-containing layer of less than one atomic layer to several atomic layers is formed on the wafer 200 (on the base film). The silicon-containing layer may be an HCD chemisorption layer. Silicon is an element that becomes a solid by itself. Here, the silicon layer includes a continuous layer made of silicon, a discontinuous layer, and a thin film formed by overlapping these layers. A continuous layer made of silicon may be referred to as a thin film. The HCD chemisorption layer includes a discontinuous chemisorption layer as well as a continuous chemisorption layer of HCD molecules. When the thickness of the silicon-containing layer formed on the wafer 200 exceeds several atomic layers, the nitriding action in step 13 described later does not reach the entire silicon-containing layer. The minimum value of the silicon-containing layer that can be formed on the wafer 200 is less than one atomic layer. Therefore, the thickness of the silicon-containing layer is preferably less than one atomic layer to several atomic layers. Note that, under the condition that the HCD gas self-decomposes, silicon is deposited on the wafer 200 to form a silicon layer. Under the condition that the HCD gas does not self-decompose, HCD is chemically adsorbed on the wafer 200 to cause HCD. A chemisorbed layer is formed. Note that it is preferable to form a silicon layer on the wafer 200 because the deposition rate can be increased, rather than forming an HCD chemical adsorption layer on the wafer 200.

As silicon-containing gas, not only HCD gas, but also inorganic raw materials such as dichlorosilane (SiH ₂ Cl ₂ , abbreviation: DCS) gas, tetrachlorosilane (SiCl ₄ , abbreviation: TCS) gas, monosilane (SiH ₄ ) gas, etc. Aminosilane-based tetrakisdimethylaminosilane ((Si (N (CH ₃ ) ₂ )) ₄ , abbreviation: 4DMAS) gas, trisdimethylaminosilane ((Si (N (CH ₃ ) ₂ )) ₃ H, abbreviation: 3DMAS) gas Bisdiethylaminosilane (Si (N (C ₂ H ₅ ) ₂ ) ₂ H ₂ , abbreviation: 2DEAS) gas, Bistally butylaminosilane (SiH ₂ (NH (C ₄ H ₉ )) ₂ , abbreviation: BTBAS) gas, etc. Organic raw materials may be used.

(Residual gas removal step (step 12))
In the residual gas removal step (step 12), after the silicon-containing layer is formed, the valve 243a is closed and the supply of the HCD gas is stopped. At this time, the APC valve 246 of the gas exhaust pipe 231 is kept open, the inside of the processing chamber 201 is evacuated by the vacuum pump 247, and the residual gas in the processing chamber 201, the vaporized gas nozzle 233a, and the vaporized gas supply pipe 240a remains unexposed. The HCD gas after contributing to the reaction or the formation of the silicon-containing layer is excluded from the processing chamber 201, the vaporized gas nozzle 233a, and the vaporized gas supply pipe 240a. At this time, the valve 243g remains open and the supply of N ₂ gas into the processing chamber 201 is maintained. This enhances the effect of removing unreacted HCD gas remaining in the processing chamber 201 or the like or contributing to the formation of the silicon-containing layer from the processing chamber 201 or the like.

As the inert gas, a rare gas such as Ar gas, He gas, Ne gas, or Xe gas may be used in addition to N ₂ gas.

(NH ₃ supply process (step 13))
In the NH ₃ supply step (step 13), the on-off valves 243c and 244c of the first supply pipe 240c are opened, and NH ₃ gas is caused to flow into the first supply pipe 240c and the reaction gas supply pipe 240b. The flow rate of NH ₃ gas flowing in the first supply pipe 240c and the reaction gas supply pipe 240b is adjusted by the mass flow controller 241c. The NH ₃ gas whose flow rate has been adjusted is exhausted from the gas exhaust pipe 231 while being supplied into the processing chamber 201 from the reaction gas supply hole 248b of the reaction gas nozzle 233b. Note that the NH ₃ gas supplied into the processing chamber 201 is activated by heat. At this time, the valve 243h is opened at the same time, and N ₂ gas is caused to flow into the second purge gas pipe 240h. The N ₂ gas is exhausted from the gas exhaust pipe 231 while being supplied into the processing chamber 201 together with the NH ₃ gas.

When the NH ₃ gas is activated by heat and flows, the APC valve 246 is adjusted appropriately so that the pressure in the processing chamber 201 is set to a pressure in the range of 50 to 3000 Pa, for example. The supply flow rate of NH ₃ gas controlled by the mass flow controller 241c is, for example, a flow rate in the range of 100 to 10,000 sccm. The supply flow rate of N ₂ gas controlled by the mass flow controller 241h is, for example, a flow rate in the range of 200 to 1000 sccm. Wafer 200 in NH ₃ gas
The exposure time, that is, the gas supply time (irradiation time) is, for example, a time within a range of 1 to 120 seconds. At this time, the temperature of the heater 207 is set to a temperature at which the temperature of the wafer 200 is in the range of 300 to 650 ° C., as in step 11. Since NH ₃ gas has a high reaction temperature and does not easily react at the wafer temperature as described above, it can be thermally activated by setting the pressure in the processing chamber 201 to a high pressure as described above. . Note that, when the NH ₃ gas is supplied by being activated by heat, a soft reaction can be caused, and nitridation described later can be performed softly.

At this time, the gas flowing into the processing chamber 201 is a thermally activated NH ₃ gas, and no HCD gas is flowing into the processing chamber 201. Therefore, the NH ₃ gas does not cause a gas phase reaction, and the activated NH ₃ gas reacts with a part of the silicon-containing layer as the first layer formed on the wafer 200 in step 11. Thereby, the silicon-containing layer is nitrided and modified into a second layer containing silicon (first element) and nitrogen (second element), that is, a silicon nitride layer (SiN layer).

  At this time, the nitridation reaction of the silicon-containing layer is not saturated. For example, when a silicon layer of several atomic layers is formed in step 11, a part of the surface layer (one atomic layer on the surface) is nitrided. That is, a part or all of a region (region where silicon is exposed) in the surface layer where nitridation can occur is nitrided. In this case, nitriding is performed under the condition that the nitridation reaction of the first layer is not saturated so that the entire first layer is not nitrided. Depending on the conditions, several layers below the surface layer of the first layer can be nitrided, but nitriding only the surface layer can improve the controllability of the composition ratio of the silicon oxynitride film. preferable. For example, when a silicon layer having one atomic layer or less than one atomic layer is formed in step 11, a part of the surface layer is similarly nitrided. Also in this case, nitriding is performed under the condition that the nitriding reaction of the first layer is not saturated so that the entire first layer is not nitrided.

As the nitrogen-containing gas, N ₂ gas, NF ₃ gas, N ₃ H ₈ gas, or the like may be used in addition to NH ₃ gas.

(Residual gas removal step (step 14))
In the residual gas removal step (step 14), after the silicon-containing layer is modified into the silicon nitride layer, the open / close valve 243c of the first supply pipe 240c is closed, and the supply of NH ₃ gas is stopped. At this time, the APC valve 246 of the gas exhaust pipe 231 is kept open, and the inside of the processing chamber 201 is evacuated by the vacuum pump 247, and the inside of the processing chamber 201, the reactive gas nozzle 233b, the reactive gas supply pipe 240b, and the first supply are supplied. The unreacted NH ₃ gas remaining in the tube 240c or after contributing to nitridation is excluded from the processing chamber 201, the reaction gas nozzle 233b, the reaction gas supply tube 240b, and the first supply tube 240c. At this time, the supply of the N ₂ gas into the processing chamber 201 is maintained while the valve 243h is kept open. This enhances the effect of removing the unreacted NH ₃ gas remaining in the processing chamber 201 and the like after contributing to nitridation from the processing chamber 201 and the like.

As the inert gas, a rare gas such as Ar gas, He gas, Ne gas, or Xe gas may be used in addition to N ₂ gas.

(O ₂ supply process (step 15))
In the O ₂ supply step (step 15), the open / close valves 243d and 244d of the second supply pipe 240d are opened, and the O ₂ gas is caused to flow into the second supply pipe 240d and the reaction gas supply pipe 240b. The flow rate of the O ₂ gas flowing through the second supply pipe 240d and the reaction gas supply pipe 240b is adjusted by the mass flow controller 241d. Further, the opening / closing valve 243h of the second purge gas pipe 240h is opened, and N ₂ gas as a participating reaction suppression gas is caused to flow into the second purge gas pipe 240h and the reaction gas supply pipe 240b. The flow rate of the N ₂ gas flowing in the second purge gas pipe 240h and the reaction gas supply pipe 240b is adjusted by the mass flow controller 241h. The flow-adjusted O ₂ gas is mixed with the flow-adjusted N ₂ gas in the reaction gas supply pipe 240b, and supplied from the reaction gas supply hole 248b of the reaction gas nozzle 233b into the processing chamber 201 while being supplied from the gas exhaust pipe 231. Exhausted. Note that the O ₂ gas supplied into the processing chamber 201 is activated by heat. However, O ₂ gas may be activated by plasma by application of high-frequency power.

When the O ₂ gas is activated and flowed by heat, the APC valve 246 is appropriately adjusted so that the pressure in the processing chamber 201 is, for example, in the range of 1 to 3000 Pa. The supply flow rate of the O ₂ gas controlled by the mass flow controller 241d is, for example, a flow rate in the range of 100 to 5000 sccm (0.1 to 5 slm). The supply flow rate of N ₂ gas as the oxidation reaction suppression gas controlled by the mass flow controller 241h is larger than the supply flow rate of O ₂ gas, for example, a flow rate in the range of 1000 to 20000 sccm (1 to 20 slm). The time for exposing the wafer 200 to the O ₂ gas, that is, the gas supply time (irradiation time) is, for example, a time within a range of 1 to 120 seconds. At this time, the temperature of the heater 207 is set to a temperature at which the temperature of the wafer 200 is in the range of 300 to 650 ° C., as in Steps 11 and 13. O ₂ gas is thermally activated under the conditions as described above. Note that the O ₂ gas is activated by heat and supplied, so that a soft reaction can be caused, and the later-described oxidation can be performed softly.

At this time, the gas flowing into the processing chamber 201 is a thermally activated O ₂ gas, and neither the HCD gas nor the NH ₃ gas is flowing into the processing chamber 201. Therefore, the O ₂ gas does not cause a gas phase reaction, and the activated O ₂ gas reacts with a part of the SiN layer as the second layer formed on the wafer 200 in Step 13. As a result, the SiN layer is oxidized to the third layer containing silicon (first element), nitrogen (second element), and oxygen (third element), that is, the silicon oxynitride layer (SiON layer). And modified.

  At this time, the oxidation reaction of the SiN layer is not saturated. For example, when a several atomic layer SiN layer is formed in steps 11 to 13, at least part of the surface layer (one atomic layer on the surface) is oxidized. In this case, the oxidation is performed under the condition that the oxidation reaction of the SiN layer is not saturated so that the entire SiN layer is not oxidized. Depending on conditions, several layers below the surface layer of the SiN layer can be oxidized, but it is preferable to oxidize only the surface layer because the controllability of the composition ratio of the silicon oxynitride film can be improved. For example, when a SiN layer having one atomic layer or less than one atomic layer is formed in Steps 11 to 13, a part of the surface layer is similarly oxidized. Also in this case, the oxidation is performed under the condition that the oxidation reaction of the SiN layer is not saturated so that the entire SiN layer is not nitrided.

As the oxygen-containing gas, in addition to O ₂ gas, O ₃ gas, NO, N ₂ O gas, or the like may be used. As the oxidation reaction suppression gas, a rare gas such as Ar, He, Ne, or Xe may be used in addition to the N ₂ gas.

(Residual gas removal step (step 16))
In the residual gas removal step (step 16), after the SiN layer is modified into the SiON layer, the open / close valve 243d of the second supply pipe 240d is closed to stop the supply of O ₂ gas. At this time, the APC valve 246 of the gas exhaust pipe 231 is kept open, and the inside of the processing chamber 201 is evacuated by the vacuum pump 247 so that the inside of the processing chamber 201, the reactive gas nozzle 233b, the reactive gas supply pipe 240b, and the second supply are exhausted. The O ₂ gas remaining in the tube 240d and not yet reacted or contributed to oxidation is excluded from the processing chamber 201, the reaction gas nozzle 233b, the reaction gas supply tube 240b, and the second supply tube 240d. At this time, the valve 243h remains open,
The supply of N ₂ gas into the processing chamber 201 is maintained. This enhances the effect of removing the unreacted or remaining O ₂ gas remaining in the processing chamber 201 and the like from the processing chamber 201 and the like. At this time, the mass flow controller 241h is controlled to change the supply flow rate of N ₂ gas supplied from the second purge gas pipe 240h from 1000 to 20000 sccm (1 to 20 slm) to 200 to 1000 sccm (0.2 to 1 slm). To do.

  By performing steps 11 to 16 described above as one cycle and performing this cycle at least once, silicon (first element), nitrogen (second element), and oxygen (third element) having a predetermined thickness are formed on the wafer 200. In other words, a silicon oxynitride film (SiON film) can be formed. The above cycle is preferably repeated a plurality of times.

(Purge and atmospheric pressure recovery process)
When a film forming step for forming a silicon oxynitride film (SiON film) at a predetermined pressure is performed, the inside of the processing chamber 201 is not exhausted by supplying an inert gas such as N ₂ gas to the processing chamber 201 and exhausting it. Purge with active gas (gas purge). Thereafter, the atmosphere in the processing chamber 201 is replaced with an inert gas (inert gas replacement), and the pressure in the processing chamber 201 is returned to normal pressure (return to atmospheric pressure).

(Substrate unloading process)
Thereafter, the seal cap 219 is lowered by the boat elevator 115, the lower end of the reaction tube 203 is opened, and the processed wafer 200 is supported by the boat 217 from the lower end of the reaction tube 203 to the outside of the reaction tube 203. Unload (boat unload). Thereafter, the processed wafer 200 is taken out from the boat 217 (wafer discharge).

(5) Exhaust Sequence Control Next, exhaust sequence control executed by the controller 280 of the substrate processing apparatus 101 according to the embodiment of the present invention will be described.

In the substrate processing step described above, a plurality of types of gases such as HCD gas, NH ₃ gas, and O ₂ gas are used. The HCD gas and NH ₃ gas are flammable gases, and the O ₂ gas is a combustion-supporting gas. For this reason, it is necessary to avoid mixing them. In addition, if the different gas reacts at a place other than on the wafer 200 and deposits are generated at the spot, it may cause clogging of pipes and nozzles and generation of particles. Ingestion should be avoided. For this purpose, the controller 280 performs exhaust sequence control as described below in the course of the substrate processing process.

In the following description, after supplying NH ₃ gas as the first processing gas in the NH ₃ supply process (step 13), the residual gas removal process (step 14) is performed, and then in the O ₂ supply process (step 15). An example of the exhaust sequence control until the start of the supply of O ₂ gas as the two process gases will be described. This is because both the NH ₃ gas and the O ₂ gas are supplied into the processing chamber 201 through the reaction gas supply pipe 240b and the reaction gas nozzle 233b, so that there is a high risk of occurrence of contamination. However, the residual gas removal step (step 12) after the HCD supply step (step 11) and the residual gas removal step (step 16) after the O ₂ supply step (step 15) are the same as described below. The exhaust sequence control is performed.

(Exhaust sequence control in the comparative example)
Here, prior to the description of the exhaust sequence control of the present embodiment, an exhaust sequence control according to a conventional configuration will be described as a comparative example with reference to FIGS. 5 and 6. FIG. 5 is a schematic diagram showing an outline of a ladder program for exhaust sequence control according to a conventional configuration serving as a reference example of the present invention. FIG. 6 is a schematic diagram showing a specific example of exhaust sequence control according to a conventional configuration serving as a reference example of the present invention.

  As shown in FIG. 5, in the exhaust sequence control of the reference example, the gas pattern panel 281 is in a “gas residual state” (refer to NG display in the figure) and “exhaust complete state” for the gas exhaust state while following instructions from the controller 280. (See OK display in the figure). In addition, the controller 280 recognizes the open / close states of all the open / close valves 243c, 244c, 243d, 244d, 243e, and 243f related to the gas exhaust in the residual gas removal step (step 14), and the switching of the valve open / close states is correctly performed. When this is done, that is, when the valve open / close state matches a predetermined exhaust condition, the exhaust of the staying gas is started and the time measurement by the timer function is started. Then, the exhaust operation is continued until a predetermined time has elapsed from the start of exhaust, and an exhaust completion signal is output to the gas pattern panel 281 when the predetermined time has elapsed. As a result, the display on the gas pattern panel 281 is switched from the “gas remaining state” to the “exhaust completed state”.

By such an exhaust sequence control of the reference example, for example, during the execution of the NH ₃ supply step (step 13) shown in FIG. 6A, that is, the on-off valves 243c and 244c are opened and the NH ₃ gas is supplied to the first supply pipe 240c. The gas pattern panel 281 indicates that the NH ₃ gas, which is the first processing gas, is in a “gas residual state” in a state where the gas flows through the inside and the reaction gas supply pipe 240b. Thereafter, as shown in FIG. 6B, for example, when the open / close valve 243c is switched to the closed state in the residual gas removal step (step 14), the timer function measures the timing when the predetermined exhaust condition regarding the NH ₃ gas is met. Is started. Then, when a certain period of time has elapsed, it is considered that exhaust of the staying gas in the first supply pipe 240c and the reaction gas supply pipe 240b is completed, and the display on the gas pattern panel 281 changes from “gas residual state” to “exhaust complete state”. ”. The O ₂ gas that is the second processing gas is not supplied or exhausted during the execution of the NH ₃ supply process (step 13) and the residual gas removal process (step 14). The display at is still in the “exhaust complete state”.

However, the switching of the valve open / close state is unlikely to cause a problem if the controller 280 performs automatic control according to a predetermined program. May be done. In this case, for example, as shown in FIG. 6 (c), even if the on-off valves 243c and 244c are switched to the closed state, the exhaust of the staying gas in the first supply pipe 240c and the reaction gas supply pipe 240b is not started. Because the exhaust condition for NH ₃ gas is not met, the time measurement by the timer function is not started, and the display on the gas pattern panel 281 is not switched even if a certain time has elapsed from the valve switching work, and the “gas remaining state” is displayed. Will remain. That is, the worker rarely notices an error immediately after the operation, and often notices the error only when the display is not switched to the “exhaust completed state” even after a certain time has passed since the operation. Therefore, if the switching of the valve open / close state is mistakenly performed, it takes a lot of time to complete the residual gas removal step (step 14) because the operator is late to notice that, and O ₂ is required. The start of the supply process (step 15) will be delayed.

(Exhaust sequence control in this embodiment)
The exhaust sequence control in the present embodiment suppresses an increase in work time due to an error in the valve opening / closing state when exhausting residual gas, which was a problem of the exhaust sequence control of the reference example described above, and thereby the next gas supply process is performed. Get started quickly.

FIG. 7 is a schematic diagram showing an outline of a ladder program for exhaust sequence control according to an embodiment of the present invention. FIG. 8 is a schematic diagram showing a specific example of the exhaust sequence control according to the embodiment of the present invention.

  As shown in FIG. 7, in the exhaust sequence control of the present embodiment, the gas pattern panel 281 is in a “gas residual state” (refer to NG display in the figure) and “exhaust state” while following the instruction from the controller 280. "(See arrow graphic display in the figure) and" Exhaust completion state "(see OK display in the figure). Since there are at least three stages, it may be displayed in four or more stages. The display modes in at least three stages are not limited to the display modes shown in the drawings as long as they can be distinguished from each other, and may be set as appropriate.

  The display mode of at least three stages is configured to be switched and displayed on an LED display which is one display part on the gas pattern panel 281. That is, on the gas pattern panel 281, a plurality of LED displays individually corresponding to the first process gas supply system, the second process gas supply system, and the like are provided, and each LED display has at least three stages. The display mode is switched. Since the display mode switching method in the LED display may use a known technique, a detailed description thereof is omitted here. In addition, each LED indicator is not limited to the thing corresponding to the display switching of three steps or more. For example, instead of switching the display in at least three stages with one LED display, at least three LED displays are arranged side by side in place of the one LED display, and each LED display is turned on / off. It is also conceivable that at least three display modes can be identified by switching. Further, the gas pattern panel 281 may be a display using a display unit in place of the LED display as long as the information regarding the valve open / close state is output in a visible manner.

  The controller 280 opens from the open state to the closed state or vice versa for at least one of all the open / close valves 243c, 244c, 243d, 244d, 243e, 243f related to gas exhaustion in the residual gas removal step (step 14). When there is a state transition, the opening / closing states of all the opening / closing valves 243c, 244c, 243d, 244d, 243e, 243f are recognized with the state transition as a trigger. Then, the recognition result is compared with a predetermined exhaust condition to determine whether or not the valve open / close state matches the predetermined exhaust condition, that is, whether or not the valve open / close state is correctly switched. The recognition of the valve open / close state may be performed using a known technique, for example, using a drive signal of an electromagnetic valve. As for the “predetermined exhaust condition”, information for specifying this is stored in advance in the information storage function of the controller 280. Further, here, the residual gas removal process (step 14) is taken as an example, but information for specifying a predetermined exhaust condition is also stored and held in advance for the other residual gas removal processes (steps 12 and 16). To do.

  When all the open / close valves 243c, 244c, 243d, 244d, 243e, and 243f are correctly switched, the exhaust of the staying gas from the first supply pipe 240c and the reaction gas supply pipe 240b is started. The At this time, the controller 280 determines that the start of exhaust is triggered when the valve open / close state matches a predetermined exhaust condition, and starts timing by the timer function. Furthermore, the controller 280 outputs a signal to the gas pattern panel 281 that the exhaust condition is satisfied and the exhaust of the staying gas is started.

Thereafter, the controller 280 considers that the exhaust of the staying gas in the first supply pipe 240c and the reaction gas supply pipe 240b is completed when a certain time has elapsed from the start of the time measurement by the timer function, and sends the exhaust completion signal to the gas pattern panel. It outputs to 281. That is, when a certain time has elapsed from the start of exhaust, it is determined that exhaust is complete. The “determined time” that is a criterion for this determination is specified in advance as a time during which exhaust of stagnant gas can be completed based on device specifications, experimental rules, and the like, and is stored in the information storage function of the controller 280. You can let it go.

  When the output signal from the controller 280 is received, the gas pattern panel 281 switches the display mode on the LED display. For example, before receiving an exhaust start signal from the controller 280, the LED display performs display in a display mode indicating the “gas remaining state” before exhaust start. Thereafter, when receiving an exhaust start signal, the LED indicator switches the display mode indicating “gas remaining state” to the display mode indicating “exhaust state” at that time. Thereafter, when an exhaust completion signal is received, the LED indicator switches the display mode indicating “exhaust state” to the display mode indicating “exhaust complete state” at that time. In other words, the LED indicator on the gas pattern panel 281 displays the “exhaust state” in a different manner from before the start of exhaust and after the completion of exhaust during the period from the start of exhaust to the end of exhaust. is there.

By the exhaust sequence control as described above, for example, during the execution of the NH ₃ supply step (step 13) shown in FIG. 8A, that is, the on-off valves 243c and 244c are opened and the NH ₃ gas is supplied into the first supply pipe 240c and In the state of flowing through the reaction gas supply pipe 240b, the gas pattern panel 281 displays that the NH ₃ gas that is the first processing gas is in a “gas remaining state”. The O ₂ gas that is the second processing gas is not supplied or exhausted during the execution of the NH ₃ supply step (step 13), so the display mode on the gas pattern panel 281 is “exhaust complete state”. Remains.

Thereafter, as shown in FIG. 8B, for example, when the open / close valve 243c is switched to the closed state in the residual gas removal step (step 14), the timer function counts when the predetermined exhaust condition for NH ₃ gas is met. And the controller 280 outputs an exhaust start signal. When this output signal is received, at the time of signal reception, the gas pattern panel 281 switches the display mode of the NH ₃ gas, which is the first process gas, on the LED display from the “residual gas state” to the “exhaust state”. When a certain time has elapsed, the controller 280 outputs an exhaust completion signal. When this output signal is received, on the gas pattern panel 281, the display mode on the LED display for the NH ₃ gas that is the first processing gas is switched from the “exhaust state” to the “exhaust completion state”. Also at this time, the O ₂ gas as the second processing gas is not supplied or exhausted during the residual gas removal step (step 14), so the display mode on the gas pattern panel 281 is “ “Exhaust completed state”.

Further, for example, as shown in FIG. 8C, when the valve switching is erroneously performed due to a manual operation error by an operator and the on-off valves 243c and 244c are switched to the closed state, the NH ₃ gas is related. Since the predetermined exhaust condition is not met, the exhaust start signal is not output from the controller 280. Therefore, even if there is a state transition with respect to the valve opening / closing, the gas pattern panel 281 shows that the display mode on the LED indicator for the NH ₃ gas that is the first processing gas remains in the “gas remaining state”. Will not switch to. Therefore, a worker who has performed a manual operation immediately notices that there has been a work mistake or the like regarding the valve open / close state by referring to the display mode on the gas pattern panel 281. In other words, even if the switching of the valve open / close state is mistakenly performed, the worker immediately notices that, and it becomes possible to correctly switch the valve open / close state by re-working. 5 and FIG. 6), it can be suppressed that a long time is required until the residual gas removing step (step 14) is completed.

(6) Effects according to the present embodiment According to the present embodiment, one or more of the following effects can be achieved.

In the substrate processing apparatus according to the present embodiment, the gas pattern panel 281 indicates the state of the gas staying in the reaction gas supply pipe 240b or the like (that is, in the pipe that is the gas flow path) in the residual gas removal step (step 14). It is displayed in at least three stages: “gas remaining state”, “exhaust state”, and “exhaust complete state”. For this reason, if the exhaust of the staying gas is not started correctly, the display on the gas pattern panel 281 does not switch from the “gas remaining state” to the “exhaust state”, and this can be recognized immediately. Therefore, when performing an exhaust sequence control that continues the exhaust operation for a certain time in order to avoid the mixture of NH ₃ gas and O ₂ gas, even if the gas exhaust does not start correctly due to an operation error, for example, the operation is immediately performed. It becomes possible to start again and to correctly start the gas exhaust, and it is possible to suppress the time required for exhaust completion compared to the exhaust sequence control in the comparative example described above.

  Further, the substrate processing apparatus according to the present embodiment has the same exhaust sequence control not only for the residual gas removal step (step 14) but also for the residual gas removal step (step 12) and the residual gas removal step (step 16). I do. That is, the gas pattern panel 281 displays the state of the staying gas not only in the reaction gas supply pipe 240b but also in the vaporized gas supply pipe 240a and the processing chamber 201. As described above, in at least one of the residual gas removal steps (Step 12, Step 14, and Step 16), the stagnant gas in at least one of the processing chamber 201, the vaporized gas supply pipe 240a, the reactive gas supply pipe 240b, and the like. By displaying this state, it becomes possible to immediately recognize if any type of gas is exhausted if the exhaust is not started correctly. As a result, the person who uses the substrate processing apparatus (for example, manual operation work) Convenience for the person).

In addition, since the substrate processing apparatus according to the present embodiment performs the exhaust sequence control that continues the exhaust operation for a predetermined time, a plurality of types of process gases that should be prevented from being mixed, such as NH ₃ gas and O ₂ gas, are used. It is suitable when applied to supply. That is, by continuing the exhaust operation for a certain period of time, for example, both the NH ₃ gas that is a combustible gas and the O ₂ gas that is a combustion-supporting gas use the reaction gas supply pipe 240b as a flow path. The NH ₃ gas and the O ₂ gas can be reliably avoided from being mixed. In addition, it is possible not only to avoid the risk of co-firing by flammable gas and combustion-supporting gas, but also different gases react at locations other than on the wafer 200 to generate deposits at the locations. This can be avoided reliably. Therefore, the deposit does not cause clogging of pipes or nozzles or cause generation of particles. As described above, the substrate processing apparatus according to the present embodiment is suitable for application when supplying a plurality of types of processing gases that should avoid intrusion, but also when supplying a single type of processing gas. In this case, it is possible to immediately recognize that the gas exhaust is not started correctly.

  In addition, since the gas pattern panel 281 performs a display in a mode different from that before and after the start of exhaust of the staying gas until the exhaust is completed, the substrate processing apparatus according to the present embodiment has started the gas exhaust correctly, Alternatively, a person using the substrate processing apparatus (for example, a manual operation worker) can easily and accurately recognize that the gas exhaust has not been started correctly.

  In particular, as in the substrate processing apparatus according to the present embodiment, if the state of the staying gas is displayed in at least three display modes of “gas residual state”, “exhaust state”, and “exhaust completion state”, the substrate processing is performed. For those who use the apparatus (for example, manual operation workers), the display contents can be recognized more easily and accurately.

In the substrate processing apparatus according to the present embodiment, since one LED display on the gas pattern panel 281 switches and displays at least three display modes, a plurality of LED displays are arranged for the switching display. Compared to the case, the required panel area is small. That is, it is possible to contribute to the miniaturization of the entire substrate processing apparatus through the miniaturization of the panel area.

  Further, in the substrate processing apparatus according to the present embodiment, when the valve open / close state matches a predetermined exhaust condition, the controller 280 determines that exhaust is started, and outputs an exhaust start signal to the gas pattern panel 281. Therefore, the criteria for determining the start of exhaust are clear, it is possible to accurately determine that the exhaust is started, and it is possible to appropriately switch the display from the “residual gas state” to the “exhaust state”. .

  Further, the substrate processing apparatus according to the present embodiment determines that the exhaust is completed when a predetermined time has elapsed from the start of exhaust, and outputs an exhaust completion signal to the gas pattern panel 281. That is, it is assumed that the exhaust is completed by using the time measurement result by the timer function. Therefore, it is not necessary to provide a large-scale configuration such as a gas concentration meter for the determination of exhaust completion while clarifying the criteria for determining exhaust completion, and the configuration of the substrate processing apparatus can be easily simplified. It becomes possible.

  By performing the substrate processing process as one of the manufacturing processes of the semiconductor device using the substrate processing apparatus according to the present embodiment as described above, it is possible to immediately recognize that the gas exhaust is not started correctly, and the exhaust is completed. As a result, it is possible to manufacture a highly efficient semiconductor device.

<Other Embodiments of the Present Invention>
In the embodiment described above, the case where the present invention is applied to a processing furnace for a SiON film is taken as an example, but the present invention is not limited to such a form. In other words, the present invention can be applied to a processing furnace of other film types regardless of the film type. For example, other films such as a nitride film, an oxide film, a metal film, and a semiconductor film are formed on a substrate. The present invention can also be suitably applied to a substrate processing apparatus and a semiconductor device manufacturing method.

  In the above-described embodiment, the case where the ALD method for alternately supplying the vaporized gas and the reactive gas onto the wafer 200 has been described, but the present invention is not limited to such a form. For example, the present invention can be suitably applied to other methods such as CVD (Chemical Vapor Deposition).

  Further, since the present invention can be implemented in various forms, the technical scope of the present invention is not limited to the above-described embodiments and examples. For example, the present invention is also applicable to the case where one or two to three sheets are processed using a sheet processing apparatus having a storage chamber for storing one or two to three wafers.

<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 processing chamber for accommodating the substrate;
A gas supply system for supplying a processing gas into the processing chamber through a pipe which is a flow path of the processing gas;
A gas exhaust system for exhausting gas in the processing chamber and the piping;
Have
A display unit for displaying a state of a staying gas in at least one of the processing chamber and the piping;
A control unit that causes the display unit to display a different mode from the start of exhaust of the staying gas to completion of exhaust, before the start of exhaust and after the completion of exhaust;
Is provided.

Preferably,
The gas supply system supplies a plurality of types of processing gases that should avoid intrusion.

Also preferably,
The control unit displays the state of the staying gas as a display mode indicating a gas residual state before the start of exhaust, a display mode indicating a state during exhaustion from the start of exhaust to the completion of exhaust, and after the completion of exhaust Is displayed on the display unit in at least three stages of the display mode indicating the exhaust completion state.

Also preferably,
The display unit is configured to switch and display the at least three display modes in one display portion.

Also preferably,
The controller determines that the exhaust is started when a valve open / close state in the pipe matches a predetermined exhaust condition.

Also preferably,
The controller determines that the exhaust is completed when a predetermined time has elapsed since the start of exhaust.

According to another aspect of the invention,
Supplying a first processing gas to a processing chamber containing a substrate through a pipe serving as a gas flow path;
Exhausting the first processing gas in the processing chamber and the piping;
Supplying a second processing gas of a type that should not be mixed with the first processing gas into the processing chamber through the piping;
Exhausting the second processing gas in the processing chamber and the piping;
In one cycle, and performing this cycle at least once to process the substrate,
In both or any one of the step of exhausting the first processing gas and the step of exhausting the second processing gas,
Using a display unit that displays the state of the staying gas in at least one of the processing chamber and the piping,
There is provided a method for manufacturing a semiconductor device in which the display unit displays different modes from the start of exhaust of the stagnant gas to the completion of exhaust before the start of exhaust and after the completion of exhaust.

DESCRIPTION OF SYMBOLS 101 Substrate processing apparatus 201 Processing chamber 231 Exhaust pipe 233a Vaporized gas nozzle 233b Reaction gas nozzle 240a Vaporized gas supply pipe 240b Reaction gas supply pipe 240c 1st supply pipe 240d 2nd supply pipe 241a Mass flow controller (MFC)
241c Mass Flow Controller (MFC)
241d Mass Flow Controller (MFC)
243a Open / close valve 243c Open / close valve 243d Open / close valve 244c Open / close valve 244d Open / close valve 245 Pressure sensor 246 APC valve 247 Vacuum pump 280 Controller 281 Gas pattern panel 500 Vaporizer

Claims (1)

A processing chamber for accommodating the substrate;
A gas supply system for supplying a plurality of types of processing gases to be prevented from being mixed into the processing chamber through piping that is a flow path of the processing gases;
A gas exhaust system for exhausting gas in the processing chamber and the piping;
Have
A substrate processing apparatus, comprising: a control unit configured to display a state of a gas staying in the pipe on a display unit in at least three stages of a gas remaining state, an exhausting state, and an exhausting complete state.