JP5344663B2 - Substrate processing apparatus, semiconductor device manufacturing method, and substrate processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate treatment device where the generation of particles and the generation of the clogging in an exhaust line are suppressed, so as to reduce the frequency of maintenance. <P>SOLUTION: The substrate treatment device comprises: a treatment tube 203 storing a wafer 200, and through which a treatment gas for forming a desired thin film on the wafer 200 is circulated, so as to treat the wafer 200; a gas feed line feeding the treatment gas or a gas for cleaning in the treatment tube 203 into the treatment tube 203; an exhaust tube 231 exhausting the atmosphere in the treatment tube 203 from a downstream region C; a heater 260 or the like adjusting the temperature of the downstream region C; and a heater 262 or the like adjusting the temperature of the exhaust line 231. The controller 280 controls the heater 260 or the like and the heater 262 or the like, thus, differentiates the temperatures of the downstream region C and the exhaust tube 231 between the time at which the treatment gas is fed into the treatment tube 203 and the time at which the gas for cleaning is fed. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

The present invention relates to a substrate processing apparatus , a semiconductor device manufacturing method, and a substrate processing method , and more particularly to a substrate processing apparatus suitable for low-temperature processing of a substrate , a semiconductor device manufacturing method, and a substrate processing method .

In this type of substrate processing apparatus, for example, an amine is selected as one of the processing raw materials for the substrate, and the processing gas is supplied to the processing container and circulated therein, whereby the substrate accommodated in the processing container is stored. On the other hand, it has become possible to realize film formation at a low temperature and has attracted particular attention in recent years. For example, TDMAT (tetrakisdimethylaminotitanium), TEMAH (tetrakisethylmethylaminohafnium), or the like can be used as the amine, and a nitride film or an oxide film such as TiN (titanium nitride) or HfO ₂ (hafnium oxide). This film can be formed.

  In this case, although the intended purpose of forming the film on the substrate at a low temperature can be achieved, since the film forming process is performed at a low temperature, the downstream region (member) of the processing gas in the processing container In addition, a film also adheres to an exhaust line (member thereof) that exhausts the atmosphere in the processing container from the downstream region, which causes particles to be generated or clogging in the exhaust line. Therefore, in the substrate processing apparatus, after the processing gas is supplied to the processing container, the cleaning gas may be exhausted from the exhaust line while being supplied to the processing container. The attached film is removed.

However, no matter how much cleaning gas is supplied, problems such as generation of particles or clogging in the exhaust line may not be sufficiently solved, resulting in maintenance of the processing vessel and exhaust line. I had to do it frequently. Accordingly, a main object of the present invention is to provide a substrate processing apparatus , a semiconductor device manufacturing method, and a substrate processing method capable of reducing the number of maintenance by suppressing generation of particles and clogging of an exhaust line. There is.

  In order to solve the above problems, the present inventor examined the cause of the generation of particles and the clogging of the exhaust line, and the cleaning gas was supplied at the same temperature as the processing gas was supplied. As a result, the film adhering to the downstream region of the processing vessel and the exhaust line cannot be removed sufficiently, or by-products resulting from the processing gas and the cleaning gas are newly added to the downstream region of the processing vessel and the exhaust line. As a result, it has been found that the generation of particles and the clogging of the exhaust line are caused, and the number of maintenance is not reduced.

Thus, according to one aspect of the present invention,
A processing container for accommodating the substrate and processing the substrate through a processing gas for forming a desired thin film on the substrate;
A gas supply line having a gas supply means for supplying the processing gas or a cleaning gas in the processing container into the processing container;
An exhaust line having exhaust means for exhausting the atmosphere of the processing container from a downstream region of the processing container;
First temperature adjusting means for adjusting the temperature of the downstream region of the processing vessel;
Second temperature adjusting means for adjusting the temperature of the exhaust line;
A controller for controlling the first temperature control means and the second temperature control means;
With
The controller controls the downstream region of the processing container and the exhaust line when the processing gas is supplied into the processing container, and the downstream region of the processing container when the cleaning gas is supplied. And controlling at least the first temperature control means and the second temperature control means so that the temperature is lower than the temperature of the exhaust line , and further supplying the cleaning gas into the processing vessel to the exhaust line. At least the gas supply means and the exhaust so as to vary the pressure inside the exhaust line a plurality of times so as to exhaust the by-products resulting from the processing gas or the cleaning gas after removing the adhered deposits A substrate processing apparatus characterized by controlling the means is provided.
According to another aspect, in the state where the temperature of the downstream region of the processing vessel and the temperature of the exhaust line are set to a first temperature that suppresses the formation of a thin film , the processing gas is supplied to the substrate accommodated in the processing vessel. Supplying a first step of forming a thin film;
A cleaning gas is supplied to the processing container in a state where the substrate is not accommodated and the temperature of the downstream region of the processing container and the temperature of the exhaust line is set to a second temperature higher than the first temperature, and the processing A second step of cleaning the interior of the container;
By-products resulting from the processing gas or the cleaning gas by changing the pressure inside the exhaust pipe connected to the processing container and exhausting the atmosphere in the processing container a plurality of times without containing the substrate A third step of exhausting
The method of manufacturing a semiconductor device which is characterized in that chromatic is provided.
Furthermore, according to another aspect, in a state where the temperature of the downstream region of the processing container and the temperature of the exhaust line are set to a first temperature that suppresses the formation of a thin film , the processing gas is supplied to the substrate accommodated in the processing container Supplying a first step of forming a thin film;
A cleaning gas is supplied to the processing container in a state where the substrate is not accommodated and the temperature of the downstream region of the processing container and the temperature of the exhaust line is set to a second temperature higher than the first temperature, and the processing A second step of cleaning the interior of the container;
By-products resulting from the processing gas or the cleaning gas by changing the pressure inside the exhaust pipe connected to the processing container and exhausting the atmosphere in the processing container a plurality of times without containing the substrate A third step of exhausting
The substrate processing method characterized by chromatic is provided.

  According to the present invention, since the temperature of the downstream region of the processing container and the exhaust line are different between the supply of the processing gas and the supply of the cleaning gas, the downstream region of the processing container is supplied when the cleaning gas is supplied. As a result, the temperature of the exhaust line can be set to a temperature that can easily remove the film adhering to the part or suppress the generation of by-products caused by the processing gas and the cleaning gas. In addition, the number of maintenance operations can be reduced by suppressing the generation of particles and clogging of the exhaust line.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

The substrate processing apparatus according to the present embodiment is configured as an example of a semiconductor manufacturing apparatus used for manufacturing a semiconductor device integrated circuit (IC).
In the following description, a case where a vertical apparatus that performs heat treatment or the like on a substrate is used as an example of the substrate processing apparatus will be described.

  As shown in FIG. 1, in the substrate processing apparatus 101, a cassette 110 containing a wafer 200 as an example of a substrate is used, and the wafer 200 is made of a material such as silicon. The substrate processing apparatus 101 includes a housing 111, and a cassette stage 114 is installed inside the housing 111. The cassette 110 is carried in or out of the cassette stage 114 by an in-factory transfer device (not shown).

  The cassette stage 114 is placed by the in-factory transfer device so that the wafer 200 in the cassette 110 maintains a vertical posture and the wafer loading / unloading port of the cassette 110 faces upward. The cassette stage 114 rotates the cassette 110 clockwise 90 degrees rearward of the casing 111 so that the wafer 200 in the cassette 110 is in a horizontal posture, and the wafer loading / unloading port of the cassette 110 faces the rear of the casing 111. It is configured to be operable.

  A cassette shelf 105 is installed in a substantially central portion of the casing 111 in the front-rear direction, and 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 the cassette 110 to be transferred by the wafer transfer mechanism 125 is stored.

  A reserve cassette shelf 107 is provided above the cassette stage 114, and is configured to store the cassette 110 in a preliminary manner.

  A cassette carrying device 118 is installed between the cassette stage 114 and the cassette shelf 105. The cassette carrying device 118 includes a cassette elevator 118a that can move up and down while holding the cassette 110, and a cassette carrying mechanism 118b as a carrying mechanism. The cassette carrying device 118 is configured to carry the cassette 110 among the cassette stage 114, the cassette shelf 105, and the spare cassette shelf 107 by continuous operation of the cassette elevator 118a and the cassette carrying mechanism 118b.

  A wafer transfer mechanism 125 is installed behind the cassette shelf 105. The wafer transfer mechanism 125 includes a wafer transfer device 125a that can rotate or linearly move the wafer 200 in the horizontal direction, and a wafer transfer device elevator 125b that moves the wafer transfer device 125a up and down. The wafer transfer device 125 a is provided with a tweezer 125 c for picking up the wafer 200. The wafer transfer device 125 loads (charges) the wafer 200 to the boat 217 by using the tweezers 125c as a placement portion of the wafer 200 by continuous operation of the wafer transfer device 125a and the wafer transfer device elevator 125b. The boat 217 is configured to be detached (discharged).

  A processing furnace 202 for heat-treating the wafer 200 is provided above the rear portion of the casing 111, and a lower end portion of the processing furnace 202 is configured to be opened and closed by a furnace port shutter 147.

  Below the processing furnace 202, a boat elevator 115 that raises and lowers the boat 217 with respect to the processing furnace 202 is provided. An arm 128 is connected to the lifting platform of the boat elevator 115, and a seal cap 219 is horizontally installed on the arm 128. The seal cap 219 is configured to support the boat 217 vertically and to close the lower end portion of the processing furnace 202.

  The boat 217 includes a plurality of holding members, and is configured to hold a plurality of (for example, about 50 to 150) wafers 200 horizontally with the centers thereof aligned in the vertical direction. Yes.

  Above the cassette shelf 105, a clean unit 134a for supplying clean air that is a cleaned atmosphere is installed. The clean unit 134a includes a supply fan and a dustproof filter, and is configured to distribute clean air inside the casing 111.

  A clean unit 134 b that supplies clean air is installed at the left end of the housing 111. The clean unit 134b also includes a supply fan and a dustproof filter, and is configured to distribute clean air in the vicinity of the wafer transfer device 125a, the boat 217, and the like. The clean air is exhausted to the outside of the casing 111 after circulating in the vicinity of the wafer transfer device 125a, the boat 217, and the like.

  Next, main operations of the substrate processing apparatus 101 will be described.

  When the cassette 110 is loaded onto the cassette stage 114 by an in-factory transfer apparatus (not shown), the cassette 110 holds the wafer 200 in a vertical posture on the cassette stage 114, and the wafer loading / unloading port of the cassette 110 is directed upward. It is placed so that it faces. Thereafter, the cassette 110 is placed in a clockwise direction 90 in the clockwise direction behind the housing 111 so that the wafer 200 in the cassette 110 is placed in a horizontal posture by the cassette stage 114 and the wafer loading / unloading port of the cassette 110 faces the rear of the housing 111. ° Rotated.

  Thereafter, the cassette 110 is automatically transported and delivered by the cassette transport device 118 to the designated shelf position of the cassette shelf 105 or the spare cassette shelf 107 and temporarily stored, and then the cassette shelf 105 or the spare cassette shelf. It is transferred from 107 to the transfer shelf 123 by the cassette transfer device 118 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 by the tweezer 125c of the wafer transfer device 125a through the wafer loading / unloading port and loaded (charged) into the boat 217. The wafer transfer device 125 a that has delivered the wafer 200 to the boat 217 returns to the cassette 110 and loads the subsequent wafer 110 into the boat 217.

  When a predetermined number of wafers 200 are loaded into the boat 217, the furnace port shutter that closed the lower end of the processing furnace 202 is opened, and the lower end of the processing furnace 202 is opened. Thereafter, the boat 217 holding the wafer group 200 is loaded into the processing furnace 202 by the ascending operation of the boat elevator 115, and the lower part of the processing furnace 202 is closed by the seal cap 219.

  After loading, arbitrary heat treatment is performed on the wafer 200 in the processing furnace 202. After the heat treatment, the wafer 200 and the cassette 110 are carried out of the casing 111 in the reverse procedure described above.

  As shown in FIGS. 2 and 3, the processing furnace 202 is provided with a heater 207 that functions as a heating means. Inside the heater 207, a processing tube 203 for accommodating a wafer 200 as an example of a substrate is provided. A lower portion of the processing tube 203 is opened, and a flange 209 made of stainless steel or the like is provided at an opening end (lower end) through an O-ring 220 that is an airtight member. The lower end opening of the flange 209 is airtightly closed by a seal cap 219 as a lid through an O-ring 220. In the processing furnace 202, at least the processing tube 203, the flange 209, the O-ring 220, and the seal cap 219 constitute a processing container for processing the wafer 200, and a processing chamber 201 is formed therein.

  A boat 217 that can hold a plurality of wafers 200 is erected on the seal cap 219 via a boat support 218. The boat support 218 is a support that supports the boat 217, and the boat 217 is inserted into the processing chamber 201 while being supported by the boat support 218. A plurality of wafers 200 to be batch-processed are stacked on the boat 217 in a horizontal posture in multiple stages in the vertical direction in FIG.

  Two gas supply pipes 232 a and 232 b for supplying a plurality of types (two types in the first embodiment) of processing gases are connected to the processing chamber 201.

  The gas supply pipe 232a is provided with a liquid mass flow controller 240, a vaporizer 242 and a valve 243a in order from the upstream direction (base end).

  The tip of the gas supply pipe 232a is connected to the nozzle 233a. The nozzle 233 a is an arc-shaped space between the inner wall of the processing tube 203 constituting the processing chamber 201 and the wafer 200, and extends in the vertical direction along the inner wall of the processing tube 203. A number of gas supply holes 248a for supplying a processing gas are provided on the side surface of the nozzle 233a. The gas supply holes 248a have the same opening area from the lower part to the upper part, and are provided at the same opening pitch.

  A carrier gas supply pipe 234a for supplying a carrier gas is connected to the gas supply pipe 232a. The carrier gas supply pipe 234a is provided with a mass flow controller 241b and a valve 243c in order from the upstream direction.

  Further, a gas supply pipe 250 for supplying a cleaning gas is connected to the gas supply pipe 232a. The gas supply pipe 250 is provided with a mass flow controller 251 and a valve 252 in order from the upstream direction.

  On the other hand, the gas supply pipe 232b is provided with a mass flow controller 241a and a valve 243b in order from the upstream direction.

  The tip of the gas supply pipe 232b is connected to the nozzle 233b. Similarly to the nozzle 233a, the nozzle 233b is an arc-shaped space between the inner wall of the processing tube 203 constituting the processing chamber 201 and the wafer 200, and extends in the vertical direction along the inner wall of the processing tube 203. ing. A large number of gas supply holes 248b for supplying a processing gas are provided on the side surface of the nozzle 233b. Similarly to the gas supply holes 248a, the gas supply holes 248b have the same opening area from the lower part to the upper part, and are provided at the same opening pitch.

  A carrier gas supply pipe 234b for supplying a carrier gas is connected to the gas supply pipe 232b. The carrier gas supply pipe 234b is provided with a mass flow controller 241c and a valve 243d in order from the upstream direction.

  Further, a gas supply pipe 255 for supplying a cleaning gas is connected to the gas supply pipe 232b. The gas supply pipe 255 is provided with a mass flow controller 256 and a valve 257 in order from the upstream direction.

  As an example of the above configuration, the liquid source is introduced into the gas supply pipe 232a. When the liquid source flows into the gas supply pipe 232a with the valve 243a opened, the liquid source is used for liquid. While the flow rate is controlled by the mass flow controller 240, the vaporizer 242 is reached, vaporized by the vaporizer 242, and the vaporized gas is supplied into the processing chamber 201 as a processing gas via the nozzle 233a.

  On the other hand, a gas source is introduced into the gas supply pipe 232b as a processing gas, and when the gas source flows into the gas supply pipe 232b with the valve 243b open, the gas source flows into the mass flow controller 241a. The gas is circulated through the gas supply pipe 232b and finally supplied to the processing chamber 201 through the nozzle 233b.

  A gas exhaust pipe 231 for exhausting the atmosphere in the processing chamber 201 is connected to the processing chamber 201 through a valve 243e. A vacuum pump 246 is connected to the gas exhaust pipe 231 so that the inside of the processing chamber 201 can be evacuated by the operation of the vacuum pump 246. The valve 243e can start and stop the vacuum evacuation of the processing chamber 201 by opening and closing operations, and can also adjust the valve opening degree and adjust the pressure inside the processing chamber 201. This is an open / close valve.

  A refrigerant flow path 290 through which a refrigerant flows is formed inside the flange 209 disposed below the processing tube 203. The refrigerant flow path 290 is connected to the refrigerant pump unit 295. The refrigerant pump unit 295 performs heat exchange (cooling) of the medium and suction / delivery of the medium, and the refrigerant is circulated (circulated) in the refrigerant flow path 270 by the operation of the refrigerant pump unit 295, so that the processing chamber 201. The lower region C and the region D near the connecting portion between the flange 209 and the gas exhaust pipe 231 can be cooled.

  A heater 260 is provided on the outer periphery of the flange 209 so that the region C and the region D can be heated. In the first embodiment, the temperature of the region C and the region D can be adjusted by the operation of the refrigerant pump unit 295 and the operation of the heater 260.

  Heaters 262 and 264 are also provided on the outer periphery of the gas exhaust pipe 231 and in the vicinity of the valve 243e so that the gas exhaust pipe 231 and the valve 243e can be heated.

  A heat insulating cover 270 is provided on the outer periphery of the heaters 262 and 264 so that heat generated from the heaters 262 and 264 can be insulated. The heat insulating cover 270 is provided with a heat exhaust duct 275 so that the heat held by the heat insulating cover 270 can be radiated from the inside to the outside of the heat insulating cover 270 (the gas exhaust pipe 231 and the valve 243e are cooled). It has become. An openable / closable heat insulating plate 277 is provided between the heat insulating cover 270 and the exhaust heat duct 275, and heat insulation and heat dissipation of the heat held by the heat insulating cover 270 are performed by opening / closing the heat insulating plate 277. It can be switched. In the first embodiment, the temperature of the gas exhaust pipe 231 and the valve 243e can be adjusted by the operation of the heaters 262 and 264 and the opening / closing operation of the open / close type heat insulating plate 277.

  A boat 217 on which a plurality of wafers 200 are placed in multiple stages at the same interval is provided at the center in the processing tube 203. The boat 217 can be moved up and down (in and out) with respect to the processing tube 203 by a boat elevator 115 (see FIG. 1). A boat rotation mechanism 267 that rotates the boat 217 is provided at the lower end of the boat 217 in order to improve processing uniformity. By driving the boat rotation mechanism 267, the boat 217 supported by the boat support 218 can be rotated.

  The liquid mass flow controller 240, mass flow controllers 241a, 241b, 241c, 251, 256, valves 243a, 243b, 243c, 243d, 243e, 252, 257, refrigerant pump unit 295, heaters 207, 260, 262, 264, Members such as the openable / closable heat insulating plate 277, the vacuum pump 246, the boat rotation mechanism 267, and the boat elevator 115 are connected to the controller 280.

  The controller 280 adjusts the flow rate of the liquid mass flow controller 240, adjusts the flow rate of the mass flow controllers 241a, 241b, 241c, 251 and 256, opens and closes the valves 243a, 243b, 243c, 243d, 252 and 257, opens and closes the valve 243e, and adjusts the pressure. Operation, operation / stop of the refrigerant pump unit 295, temperature adjustment of the heaters 207, 260, 262, 264, opening / closing operation of the open / close type heat insulating plate 277, operation / stop of the vacuum pump 246, adjustment of the rotation speed of the boat rotation mechanism 267, boat The elevator 115 is controlled to move up and down.

  Subsequently, a film forming method (including a substrate processing apparatus cleaning method) according to the first embodiment will be described.

  As shown in FIG. 4, the film forming method according to the first embodiment mainly includes three steps: a film forming step X, a cleaning step Y, and an ATM (ATMosphere: atmospheric pressure) cycle purge step Z. In the film forming method, the cleaning step Y is periodically executed every time the film forming step X is repeated a predetermined number of times, and the ATM cycle purge step is periodically performed after the cleaning step Y is executed a predetermined number of times. The process of Z is executed.

  Hereinafter, each process of the film forming step X, the cleaning step Y, and the ATM cycle purge step Z will be described step by step.

[Film formation step X]
An example of forming a TiN film using TDMAT (tetrakisdimethylaminotitanium) and NH ₃ (ammonia), which is one of the manufacturing steps of a semiconductor device (semiconductor device), as an example of a film forming process using the ALD method. Based on the explanation.

  An ALD (Atomic Layer Deposition) method, which is one of CVD (Chemical Vapor Deposition) methods, uses 1 process gas as at least two kinds of raw materials used for film formation under certain film formation conditions (temperature, time, etc.). In this method, the materials are alternately supplied onto the substrate, adsorbed onto the substrate in units of one atom, and a film is formed using a surface reaction. At this time, the film thickness is controlled by the number of cycles for supplying the processing gas (for example, if the film forming speed is 1 kg / cycle, 20 cycles are performed when a 20 mm film is formed).

In the ALD method, for example, when a TiN film is formed, high quality film formation is possible at a low temperature of 150 ° C. using TDMAT and NH ₃ .

  First, as described above, the wafer 200 is loaded into the boat 217 and loaded into the processing chamber 201. When the boat 217 is carried into the processing chamber 201, the boat 217 and the wafer 200 held by the boat rotation mechanism 267 are rotated, and four steps described later are sequentially executed.

(Step 1)
In a state where the vacuum pump 246 is operated, TDMAT is caused to flow into the gas supply pipe 232a and carrier gas is caused to flow into the carrier gas supply pipe 234a and the carrier gas supply pipe 234b, respectively. An inert gas such as N ₂ (nitrogen) or Ar (argon) can be used as the carrier gas, and N ₂ is used as the carrier gas in the first embodiment.

  In this state, the valve 243a of the gas supply pipe 232a, the valve 243c of the carrier gas supply pipe 234a, the valve 243d of the carrier gas supply pipe 234b, and the valve 243e of the gas exhaust pipe 231 are opened.

  The liquid TDMAT flowing in from the gas supply pipe 232a is vaporized by the vaporizer 242 while the flow rate is adjusted by the mass flow controller 240, and reaches the connecting portion between the gas supply pipe 232a and the carrier gas supply pipe 234a.

  The carrier gas flowing in from the carrier gas supply pipe 234a flows through the carrier gas supply pipe 234a while the flow rate is adjusted by the mass flow controller 241b, and reaches the connecting portion between the gas supply pipe 232a and the carrier gas supply pipe 234a.

  The vaporized gas and the carrier gas of TDMAT merge at the connecting portion of the gas supply pipe 232a and the carrier gas supply pipe 234a, and then are mixed and supplied from the nozzle 233a to the processing chamber 201, and finally the gas exhaust Exhaust from the tube 231.

  The carrier gas flowing in from the carrier gas supply pipe 234b flows through the carrier gas supply pipe 234b and the gas supply pipe 232b while the flow rate is adjusted by the mass flow controller 241c, and is supplied from the nozzle 233b to the processing chamber 201, and finally gas exhaust. Exhaust from the tube 231.

  In step 1, the controller 280 controls the operation of the heater 207, the mass flow controller 240, the valve 243a, etc., the opening degree of the valve 243e, etc., and maintains the pressure in the processing chamber 201 at an optimum value within a certain range. The supply amount of TDMAT is set to 0.1 to 1 g / min, the time for exposing the vaporized gas of TDMAT to the wafer 200 is set to 5 to 20 seconds, and the temperature of the wafer 200 in the processing chamber 201 is set to 150 ° C.

  In the above-described step 1, as described above, the vaporized gas of TDMAT is supplied into the processing chamber 201 as a processing gas, so that the TDMAT reacts with the surface portion such as the base film on the wafer 200 (chemical adsorption).

(Step 2)
The supply of the vaporized gas of TDMAT is stopped by closing the valve 243a of the gas supply pipe 232a, and the supply of the carrier gas is also stopped by closing the valve 241c of the carrier gas supply pipe 234a and the valve 243d of the carrier gas supply pipe 234b.
At this time, the valve 243e of the gas exhaust pipe 231 is kept open, and the inside of the processing chamber 201 is exhausted to 20 Pa or less by the vacuum pump 246, and the TDMAT vaporized gas remaining in the processing chamber 201 and the like is discharged from the processing chamber 201. Exclude.

  In step 2, the carrier gas may continue to be supplied to the processing chamber 201 with both or one of the valve 243c of the carrier gas supply tube 234a and the valve 243d of the carrier gas supply tube 234b kept open. The effect of removing the vaporized gas of TDMAT remaining in 201 etc. from the processing chamber 201 is further enhanced.

(Step 3)
NH ₃ is allowed to flow into the gas supply pipe 232b and carrier gas is allowed to flow into the carrier gas supply pipe 234a and the carrier gas supply pipe 234b, respectively. In this state, the valve 243b of the gas supply pipe 232b, the valve 243c of the carrier gas supply pipe 234a, and the valve 243d of the carrier gas supply pipe 234b are opened.

The NH ₃ flowing from the gas supply pipe 232b flows through the gas supply pipe 232b while the flow rate is adjusted by the mass flow controller 241a, and reaches the connection portion between the gas supply pipe 232b and the carrier gas supply pipe 234b.

  The carrier gas flowing in from the carrier gas supply pipe 234b flows through the carrier gas supply pipe 234b while the flow rate is adjusted by the mass flow controller 241c, and reaches the connecting portion between the gas supply pipe 232b and the carrier gas supply pipe 234b.

NH ₃ and the carrier gas are merged at the connecting portion of the gas supply pipe 232b and the carrier gas supply pipe 234b, and then mixed and supplied from the nozzle 233b to the processing chamber 201, and finally the gas exhaust pipe 231. Exhausted from.

  The carrier gas flowing in from the carrier gas supply pipe 234a flows through the carrier gas supply pipe 234a and the gas supply pipe 232a while the flow rate is adjusted by the mass flow controller 241b, is supplied from the nozzle 233a to the processing chamber 201, and is finally exhausted from the gas. Exhaust from the tube 231.

In step 3, the controller 280 controls the operation of the heater 207, valve 243b, etc., the opening degree of the valve 243e, etc., and maintains the pressure in the processing chamber 201 at an optimum value within a certain range, so that NH ₃ is kept in the wafer. The exposure time to 200 is set to 10 to 20 seconds, and the temperature of the wafer 200 in the processing chamber 201 is set to 80 ° C. as in Step 1.

In step 3 described above, NH ₃ is supplied as a processing gas to the processing chamber 201 as described above, whereby TDMAT chemically adsorbed on the surface of the wafer 200 reacts with NH ₃ to form a TiN film on the wafer 200. To do.

(Step 4)
After film formation, the valve 243b of the gas supply pipe 232b is closed to stop the supply of NH ₃ , and the valve 243c of the carrier gas supply pipe 234a and the valve 243d of the carrier gas supply pipe 234b are closed to stop the supply of carrier gas. To do. At this time, the valve 243e of the gas exhaust pipe 231 is kept open, the inside of the processing chamber 201 is evacuated by the vacuum pump 246, and the NH ₃ remaining in the processing chamber 201 or the like and contributing to the film formation is removed. Exclude.

In Step 4, as in Step 2, the carrier gas may continue to be supplied to the processing chamber 201 with both or one of the valve 243c of the carrier gas supply pipe 234a and the valve 243d of the carrier gas supply pipe 234b kept open. In this case, the effect of eliminating the NH ₃ remaining in the processing chamber 201 and the like and contributing to the film formation from the processing chamber 201 is further enhanced.

  Thereafter, the TiN film having a predetermined thickness can be formed on the wafer 200 by repeating the process of the film forming step X a plurality of times with the above-described steps 1 to 4 as one cycle (film forming step X).

  Here, in the film forming step X, the refrigerant pump unit 295 is controlled by the controller 280, and the refrigerant is circulated inside the flange 209 so that the temperatures of the regions C and D are set to room temperature (about 30 ° C.). Further, the controller 280 controls the heaters 262 and 264 (without operating the heaters 262 and 264), and the temperatures of the gas exhaust pipe 231 and the valve 243e are also set to room temperature. As a result, it is possible to suppress the formation of a TiN film on the flange 209, the seal cap 219, the gas exhaust pipe 231 and the valve 243e. This temperature control is basically performed throughout steps 1 to 4.

[Cleaning step Y]
In a state where the vacuum pump 246 is operated, a cleaning gas is caused to flow into the gas supply pipe 250 and the gas supply pipe 255, and a carrier gas is caused to flow into the carrier gas supply pipe 234a and the carrier gas supply pipe 234b, respectively. . As the cleaning gas, NF ₃ (nitrogen trifluoride), ClF ₃ (chlorine trifluoride), or the like can be used. In the first embodiment, NF ₃ is used as the cleaning gas.

  In this state, the valve 252 of the gas supply pipe 250, the valve 257 of the gas supply pipe 255, the valve 243c of the carrier gas supply pipe 234a, the valve 243d of the carrier gas supply pipe 234b, and the valve 243e of the gas exhaust pipe 231 Open.

The NF ₃ flowing in from the gas supply pipe 250 flows through the gas supply pipe 250 while the flow rate is adjusted by the mass flow controller 251, and reaches the connecting portion between the gas supply pipe 250 and the carrier gas supply pipe 234a. After that, the NF ₃ is supplied to the processing chamber 201 from the nozzle 233a in a mixed state with the carrier gas in the same manner as the vaporized gas of TDMAT (see step 1 of the film forming step X), and finally the gas The exhaust pipe 231 is exhausted.

On the other hand, the NF ₃ flowing in from the gas supply pipe 255 flows through the gas supply pipe 255 while the flow rate is adjusted by the mass flow controller 256, and reaches the connecting portion between the gas supply pipe 255 and the carrier gas supply pipe 234b. After that, the NF ₃ is supplied to the processing chamber 201 from the nozzle 233b in a mixed state with the carrier gas in the same manner as NH ₃ (see step 3 of the film forming step X), and finally the gas exhaust pipe 231 is exhausted.

  At this time, the controller 280 controls the heaters 260, 262, and 264 to set the temperature of the region C and the region D and the gas exhaust pipe 231 to 150 ° C., the temperature of the valve 243e to 190 ° C. Have different temperatures.

  That is, in the film forming step X, the temperatures of the region C and the region D, the gas exhaust pipe 231 and the valve 243e are set to room temperature so as to suppress the formation of the TiN film. On the other hand, in the cleaning step Y, since it is not necessary to consider the formation of the TiN film, the temperature of the region C and the region D, the gas exhaust pipe 231 and the valve 243e is set to 150 ° C. or 190 ° C., and the TiN film can be easily removed. It is said.

  In addition, during the process of the film forming step X and the cleaning step Y, as a general rule, the openable and heat insulating plate 277 is closed (the openable and heat insulating plate 277 may be opened when it is desired to dissipate the heat inside the heat insulating cover 270). .), During the transition from the cleaning step Y to the film forming step X, the controller 280 opens the openable heat insulating plate 277 to dissipate the heat held in the heat insulating cover 270 from the exhaust heat duct 275, The exhaust pipe 231 and the valve 243e are cooled.

  As a result, heat loss of the gas exhaust pipe 231 and the valve 243e can be suppressed during the film forming step X and the cleaning step Y. On the other hand, during the transition from the cleaning step Y to the film forming step X, Can quickly switch the temperature of the gas exhaust pipe 231 and the valve 243e (switching the temperature from 150 ° C. or 190 ° C. to room temperature).

[ATM cycle purge step Z]
The controller 280 controls the valve 243e and the vacuum pump 246 to vary the pressure inside the gas exhaust pipe 231 and the valve 243e alternately between “atmospheric pressure” and “low vacuum pressure”, and the gas exhaust pipe 231 And the pressure inside the valve 243e is rapidly changed. In other words, this cycle is repeated a plurality of times, with one cycle starting from the atmospheric pressure to the low vacuum pressure and returning to the atmospheric pressure again. For example, the pressure fluctuation rate between the atmospheric pressure and the low vacuum pressure is set to 15 Torr / second, the time is set to 6 minutes per cycle, and this is executed for 120 cycles.

  In the first embodiment, since the temperatures of the region C and the region D, the gas exhaust pipe 231 and the valve 243e are controlled to a low temperature of room temperature in the film forming step X, the flange 209, the seal cap 219, the gas exhaust pipe 231, It is possible to prevent the TiN film from adhering to a member such as the valve 243e. That is, as shown in FIG. 5, when a TiN film is formed, the film thickness increases as the temperature increases from around room temperature to around 100 ° C. (FIG. 5 shows the process after film forming step X is performed about 100 times. When the temperature exceeds about 100 ° C., the film thickness remains almost constant regardless of the temperature rise. Therefore, if the temperatures of the region C and the region D, the gas exhaust pipe 231 and the valve 243e are maintained as low as room temperature as in the film forming step X, the flange 209, the seal cap 219, the gas exhaust pipe 231 and the valve 243e, etc. It is possible to suppress the TiN film from adhering to the member.

In contrast, in the cleaning step Y, the temperature of the region C and the region D and the gas exhaust pipe 231 is controlled to 150 ° C., and the temperature of the valve 243e is controlled to 190 ° C., so the flange 209, the seal cap 219, the gas exhaust The TiN film remaining on the members such as the tube 231 and the valve 243e can be quickly and easily removed. That is, as shown in FIG. 6, when the TiN film is removed (etched) with NF ₃ , the etching rate increases as the temperature rises. Therefore, as in the cleaning step Y, if the temperatures of the regions C and D, the gas exhaust pipe 231 and the valve 243e are maintained at a high temperature of 150 ° C. or 190 ° C., the flange 209, the seal cap 219, the gas exhaust pipe 231 and the valve The TiN film remaining on the member such as 243e can be quickly and easily removed (the temperatures of the region C and region D, the gas exhaust pipe 231 and the valve 243e in the cleaning step Y are higher than 150 ° C. and 190 ° C. Although the temperature is preferable for enhancing the cleaning action, the temperature is suppressed to such a temperature in the first embodiment because the heat resistance of members such as the O-ring 220 is taken into consideration.

Further, in the cleaning step Y, the temperature of the region C and the region D and the gas exhaust pipe 231 is controlled to 150 ° C., and the temperature of the valve 243e is controlled to 190 ° C., so that the processing gas (TDMAT, NH ₃ ) or cleaning gas is controlled. Even if a by-product (NH ₄ F or the like) due to (NF ₃ ) is newly generated, the by-product can be sublimated, and the by-product can be flange 209, seal cap 219, gas exhaust pipe 231. Adhering to members such as the valve 243e can be suppressed.

  As described above, in the first embodiment, the temperatures of the region C and the region D, the gas exhaust pipe 231, and the valve 243e are made different between the film forming step X and the cleaning step Y. Therefore, the flange 209, the seal cap 219, and the gas exhaust While suppressing the adhesion of the TiN film to the members such as the tube 231 and the valve 243e, the deposits can be removed quickly and easily, and new by-products resulting from the processing gas and the cleaning gas Can also be suppressed. As a result, generation of particles and clogging of the exhaust line can be suppressed and the number of maintenance can be reduced. As a result, stable operation of the substrate processing apparatus 101 and improvement of throughput (processing amount per unit time) can be achieved. And can be realized.

Further, in the first embodiment, the processing of the ATM cycle purge step Z is executed to apply a sudden pressure fluctuation to the gas exhaust pipe 231 and the valve 243e. Therefore, after the processing of the cleaning step Y, FIG. As shown, by-product 300 (NH ₄ F or the like) resulting from the processing gas (TDMAT, NH ₃ ) or the cleaning gas (NF ₃ ) may remain attached to the gas exhaust pipe 231 or the valve 243e. The by-product 300 can be peeled and discharged from the gas exhaust pipe 231 or the valve 243e. As a result, generation of particles and clogging of the exhaust line can be reliably suppressed.

  Regarding the temperatures of the region C and the region D, the gas exhaust pipe 231 and the valve 243e, the temperature of the film forming step X is lower than the temperature of the cleaning step Y (the temperature of the cleaning step Y is higher than the temperature of the film forming step X). There is no need to do this, and vice versa. Of course, the value of the temperature itself in the film forming step X, the value of the temperature itself in the cleaning step Y, and the like may be appropriately changed according to the type of the processing gas and the cleaning gas.

For example, when forming a Si ₃ N ₄ film, the temperature of the film forming step X is set higher than the temperature of the cleaning step Y, and the temperature values of the film forming step X and the cleaning step Y are also changed. In this case, preferably, in the film forming step X, the region C is 150 ° C., the region D is 120 ° C., the gas exhaust pipe 251 is 150 ° C., and the valve 243e is 190 ° C. On the other hand, in the cleaning step Y, the region C is set to 100 ° C., the region D is set to 120 ° C., the gas exhaust pipe 251 is set to 100 ° C., and the valve 243e is set to 80 ° C.

  The second embodiment is mainly different from the first embodiment in the following points, and is otherwise the same as the first embodiment.

In the second embodiment, instead of TDMAT and NH ₃ as processing gas materials, TEMAH (tetrakisethylmethylaminohafnium) and O ₃ (ozone) are used to form an HfO ₂ (hafnium oxide) film. Indicates.

When the HfO ₂ film is formed using TEMAH and O ₃ , for example, high-quality film formation is possible at a low temperature of 180 to 250 ° C.

  In step 1 of the film forming step X, TEMAH is caused to flow into the gas supply pipe 232a, and the vaporized gas of TEMAH is supplied into the processing chamber 201 as a processing gas. React (chemisorption).

  At this time, the pressure in the processing chamber 201 is maintained at an optimal value within a certain range, the supply amount of TEMAH is set to 0.01 to 0.1 g / min, and the time for exposing the vaporized gas of TEMAH to the wafer 200 is set to 30 to 30 minutes. The temperature of the wafer 200 in the processing chamber 201 is set to an optimum value within a range of 180 to 250 ° C. for 180 seconds.

On the other hand, in step 3 of the film forming step X, O ₃ is allowed to flow into the gas supply pipe 232b, O ₃ is supplied as a processing gas to the processing chamber 201, and TEMAH and O ₃ chemically adsorbed on the surface of the wafer 200 are supplied. By reacting, an HfO ₂ film is formed on the wafer 200.

At this time, the pressure in the processing chamber 201 is maintained at an optimum value within a certain range, the time during which O ₃ is exposed to the wafer 200 is set to 10 to 120 seconds, and the temperature of the wafer 200 in the processing chamber 201 is set to the TEMAH in Step 1. It is set to an optimum value within the range of 180 to 250 ° C. as in the case of supplying the vaporized gas.

Then, by repeating the process of the film forming step X a plurality of times, a HfO ₂ film having a predetermined thickness is formed on the wafer 200.

In the film forming step X and the cleaning step Y, the temperature of the film forming step X can suppress adhesion of the HfO ₂ film with respect to the temperature of the regions C and D, the gas exhaust pipe 231 and the valve 243e. The temperature of the cleaning step Y is different from the temperature of the film forming step X, and a temperature at which the HfO ₂ film can be removed quickly and easily (for example, 150 ° C.). And As a result, as in the first embodiment, the number of maintenance operations can be reduced by suppressing the generation of particles and the clogging of the exhaust line.

  As mentioned above, although the preferable Example of this invention was described, according to the preferable embodiment of this invention, while containing a board | substrate, the process gas for forming a desired thin film on the said board | substrate distribute | circulated, and the said board | substrate A processing container to be processed, a gas supply line for supplying the processing gas or a cleaning gas in the processing container into the processing container, and an exhaust line for exhausting the atmosphere of the processing container from a downstream region of the processing container; The first temperature adjusting means for adjusting the temperature of the downstream region of the processing vessel, the second temperature adjusting means for adjusting the temperature of the exhaust line, the first temperature adjusting means, and the second temperature adjusting means A control unit for controlling the means, and the control unit controls at least the first temperature control means and the second temperature control means to supply the processing gas into the processing container. The cleaning gas There at the time supplied, a substrate processing apparatus, characterized by varying the downstream region and the temperature of the exhaust line of the processing chamber is provided.

  Preferably, the reaction vessel includes a processing tube which forms a space for processing the substrate and has an opening at one end thereof, and the first temperature control unit adjusts the temperature on the opening side of the processing tube, and the control The control unit controls at least the first temperature control unit and the second temperature control unit so that the processing gas is supplied into the processing tube and the cleaning gas is supplied. The opening side of the pipe and the temperature of the exhaust line are made different.

  Preferably, the first temperature adjusting unit includes a heating unit that heats a downstream region of the processing container and a cooling unit that cools the downstream region of the processing container.

  Preferably, the second temperature adjusting means has a heating means for heating the exhaust line, and more preferably, the second temperature adjusting means is a heat insulating means for insulating heat from the heating means and the heating means. More preferably, the second temperature adjusting means includes the heating means, the heat insulating means, and a heat radiating means for radiating heat held by the heat insulating means.

1 is a perspective view illustrating a schematic configuration of a substrate processing apparatus according to a preferred embodiment (Example 1) of the present invention. It is a schematic block diagram of the vertical processing furnace used in the preferable Example of this invention, and the member accompanying it, and has shown the processing furnace part with the longitudinal cross-section especially. It is the sectional view on the AA line of FIG. 3 is a flowchart schematically showing a film forming method using a substrate processing apparatus according to a preferred embodiment of the present invention. 1 is a diagram illustrating a schematic relationship between a film thickness and a temperature of a film-formed product according to a preferred embodiment of the present invention. 1 is a diagram illustrating a schematic relationship between a film removal rate and a temperature according to a preferred embodiment of the present invention. 6 is a diagram for schematically illustrating removal of by-products from an exhaust line when an ATM cycle purge step according to a preferred embodiment of the present invention is performed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Substrate processing apparatus 105 Cassette shelf 107 Reserve cassette shelf 110 Cassette 111 Case 114 Cassette stage 115 Boat elevator 118 Cassette transfer device 118a Cassette elevator 118b Cassette transfer mechanism 123 Transfer shelf 125 Wafer transfer mechanism 125a Wafer transfer device 125b Wafer transfer Mounting device elevator 125c tweezer 128 arm 134a, 134b clean unit 147 furnace port shutter 200 wafer 202 processing furnace 203 processing pipe 207 heater 209 flange 217 boat 218 boat support 219 seal cap 220 O-ring 231 gas exhaust pipe 232a, 232b gas supply pipe 233a, 233b Nozzle 234a, 234b Carrier gas supply pipe 240 Mass flow controller for liquid 241a, 241b, 241c Mass flow controller 242 Vaporizer 243a, 243b, 243c, 243d, 243e Valve 246 Vacuum pump 248a, 248b Gas supply hole 267 Boat rotation mechanism 250, 255 Gas supply pipe 251, 256 Mass flow controller 252, 257 Valve 260, 262, 264 Heater 270 Heat insulation cover 275 Waste heat duct 277 Openable heat insulation plate 280 Controller 290 Refrigerant flow path 295 Refrigerant pump unit

Claims (3)

A processing container for accommodating the substrate and processing the substrate through a processing gas for forming a desired thin film on the substrate;
A gas supply line having a gas supply means for supplying the processing gas or a cleaning gas in the processing container into the processing container;
An exhaust line having exhaust means for exhausting the atmosphere of the processing container from a downstream region of the processing container;
First temperature adjusting means for adjusting the temperature of the downstream region of the processing vessel;
Second temperature adjusting means for adjusting the temperature of the exhaust line;
A controller for controlling the gas supply means, the exhaust means, the first temperature adjustment means, and the second temperature adjustment means;
With
The controller controls the downstream region of the processing container and the exhaust line when the processing gas is supplied into the processing container, and the downstream region of the processing container when the cleaning gas is supplied. The cleaning gas is supplied into the processing vessel and attached to the exhaust line while controlling at least the first temperature control means and the second temperature control means so as to be lower than the temperature of the exhaust line. In order to exhaust the by-product resulting from the processing gas or the cleaning gas, the atmospheric pressure and the vacuum pressure are alternately changed, and the pressure inside the exhaust line is changed several times. A substrate processing apparatus, wherein at least the gas supply means and the exhaust means are controlled to vary. First, a thin film is formed by supplying a processing gas to the substrate accommodated in the processing container in a state where the temperature of the downstream region of the processing container and the temperature of the exhaust line are set to a first temperature that suppresses the formation of the thin film. And the process of
A cleaning gas is supplied to the processing container in a state where the substrate is not accommodated and the temperature of the downstream region of the processing container and the temperature of the exhaust line is set to a second temperature higher than the first temperature, and the processing A second step of cleaning the interior of the container;
In the state where the substrate is not accommodated , the processing gas is changed by alternately changing the pressure inside the exhaust pipe that is connected to the processing container and exhausts the atmosphere in the processing container, and is changed a plurality of times. Or a third step of exhausting by-products resulting from the cleaning gas;
A method for manufacturing a semiconductor device, comprising: First, a thin film is formed by supplying a processing gas to the substrate accommodated in the processing container in a state where the temperature of the downstream region of the processing container and the temperature of the exhaust line are set to a first temperature that suppresses the formation of the thin film. And the process of
A cleaning gas is supplied to the processing container in a state where the substrate is not accommodated and the temperature of the downstream region of the processing container and the temperature of the exhaust line is set to a second temperature higher than the first temperature, and the processing A second step of cleaning the interior of the container;
In the state where the substrate is not accommodated , the processing gas is changed by alternately changing the pressure inside the exhaust pipe that is connected to the processing container and exhausts the atmosphere in the processing container, and is changed a plurality of times. Or a third step of exhausting by-products resulting from the cleaning gas;
A substrate processing method comprising:

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