JP2012134332A - Substrate processing method and substrate processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for reducing consumption of a material gas and a reaction gas.SOLUTION: A substrate processing method performs the following steps alternately several times: a film generation step S1 of forming a silicon-containing film with respect to a substrate in a processing chamber while supplying and exhausting a hydrogen-containing gas and a silicon-containing gas to and from the substrate and absorbing heat from the substrate; and a temperature re-raising step S2 of stopping supply of the hydrogen-containing gas and the silicon-containing gas and raising the temperature of the substrate. This enables suppression of a decrease in a growth rate of the silicon-containing film, thereby reducing the consumption of a material gas and a reaction gas.

Description

  The present invention relates to a substrate processing technique and a substrate processing apparatus, and more particularly to a substrate processing apparatus that supplies a gas into a processing chamber and forms a film on a substrate, and a technique that is effective when applied to the processing technique.

  In Japanese Patent Laid-Open No. 6-177705 (Patent Document 1), a compound source gas containing silicon as a main constituent element is thermally decomposed in a reaction vessel, and polycrystalline silicon (poly- A method for depositing a Si) layer is described. In Patent Document 1, by supplying atomic hydrogen in the course of depositing a polycrystalline silicon layer, bonded hydrogen contained in the layer can be desorbed without using a heating action.

  Japanese Patent Laid-Open No. 10-125603 (Patent Document 2) discloses that a silicon film is formed on a holding surface of a susceptor before a silicon thin film is formed on a semiconductor wafer by epitaxial growth. A method is described for removing this after absorption.

Japanese Patent Laying-Open No. 2008-277777 (Patent Document 3) describes a method of selectively growing an epitaxial film on a silicon surface of a substrate. In Patent Document 3, a step of forming a film by introducing SiH ₄ and H ₂ , a step of removing SiH ₄ from the processing chamber by H ₂ purge, an unnecessary nucleus on the insulating film by introducing Cl ₂ and H ₂ It is described that a required epitaxial film is selectively formed by repeating the steps of removing (etching) and removing Cl ₂ by purging with H ₂ .

Japanese Patent Laid-Open No. 6-177705 JP-A-10-125603 JP 2008-277777 A

  In a substrate processing process, a substrate processing apparatus that performs a film forming process on a substrate is widely used. In this substrate processing apparatus, a film is formed on a substrate by heating a substrate disposed in a processing chamber of the substrate processing apparatus and introducing a source gas into the processing chamber. For example, when a silicon-containing gas containing silicon element as a source gas and a hydrogen-containing gas containing hydrogen element as a reaction gas are supplied, silicon is deposited on the substrate by thermal decomposition of the silicon-containing gas or reaction of the silicon-containing gas and the hydrogen-containing gas. A containing film is formed.

  As a result of examining the substrate processing technique, the present inventor has found the following problems. First, there is a problem that the temperature of the substrate decreases during the film forming process. When a silicon-containing film is formed by thermal decomposition or reaction, the film formation rate can be maintained by keeping the temperature of the substrate in the processing chamber at a predetermined processing temperature. However, there is a problem that the temperature is lowered due to heat removal from the substrate due to heat exchange with the gas supplied onto the substrate or reaction of the gas. For example, the temperature of the substrate is likely to decrease over time due to the endothermic action of the source gas having a specific heat higher than that of the reaction gas. In addition, for example, when a product film is formed by utilizing a gas reaction, if an endothermic reaction occurs, there is a problem that the temperature of the substrate is reduced due to the heat of the substrate being taken away. Moreover, when forming a product film | membrane using reaction of gas, the quantity of the by-product produced | generated at the time of reaction increases with time, and there exists a problem which becomes an obstructive factor which reduces the film-forming speed | rate.

  As described above, when the film formation rate decreases, the utilization efficiency of the source gas and the reaction gas (the ratio contributing to the formation of the generated film) decreases. As a result, the consumption amount of the source gas and the reaction gas (the total amount supplied when forming the generated film) increases.

  This invention is made | formed in view of the said subject, The objective is to provide the technique which reduces the consumption of raw material gas and a reactive gas.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

  That is, the substrate processing apparatus according to the present invention supplies a hydrogen-containing gas and a silicon-containing gas to a substrate in the processing chamber, discharges it, and forms a silicon-containing film on the substrate while absorbing heat from the substrate. And the step of stopping the supply of the hydrogen-containing gas and the silicon-containing gas and raising the temperature of the substrate are alternately performed a plurality of times.

  The effects obtained by typical ones of the inventions disclosed in the present application will be briefly described as follows.

  That is, it is possible to suppress the product generated by thermal decomposition or gas reaction from adhering to the periphery of the processing chamber.

It is a figure which shows schematic structure of the substrate processing apparatus in one embodiment of this invention. It is a top view which shows the state which has loaded the wafer into the susceptor. It is sectional drawing cut | disconnected by the AA line of FIG. It is sectional drawing which shows a mode that a wafer is removed from a susceptor. It is a side view which shows the whole structure of a boat. It is a top view which shows a mode that the susceptor with which the wafer was mounted in the boat is loaded. It is an expanded sectional view along the BB line of FIG. It is a longitudinal cross-sectional view which shows schematic structure of the processing furnace of a substrate processing apparatus shown in FIG. 1, and a processing furnace periphery. It is a cross-sectional view which shows the schematic block diagram of the processing furnace shown in FIG. It is explanatory drawing which shows the sequence of the process process of the board | substrate in one embodiment of this invention. FIG. 11 is an explanatory diagram illustrating a relationship among a flow rate of a processing gas, a wafer temperature, and a growth rate of a silicon-containing film in the H ₂ purge process, the temperature raising process, and the film forming process illustrated in FIG. It is explanatory drawing which shows the modification with respect to FIG. It is a longitudinal cross-sectional view which shows the modification with respect to FIG. It is explanatory drawing which shows the modification with respect to FIG. It is explanatory drawing which shows the modification with respect to FIG. It is explanatory drawing which shows the modification with respect to FIG. It is explanatory drawing which shows the modification with respect to FIG. It is explanatory drawing which shows the modification with respect to FIG. It is a longitudinal cross-sectional view which shows the modification with respect to FIG. It is explanatory drawing which shows the modification with respect to FIG. It is explanatory drawing which shows the comparative example with respect to FIG.

  In the following embodiments, when it is necessary for the sake of convenience, the description will be divided into a plurality of sections or embodiments. However, unless otherwise specified, they are not irrelevant to each other. There are some or all of the modifications, details, supplementary explanations, and the like.

  Further, in the following embodiments, when referring to the number of elements (including the number, numerical value, quantity, range, etc.), especially when clearly indicated and when clearly limited to a specific number in principle, etc. Except, it is not limited to the specific number, and may be more or less than the specific number.

  Further, in the following embodiments, the constituent elements (including element steps and the like) are not necessarily indispensable unless otherwise specified and apparently essential in principle. Needless to say.

  Similarly, in the following embodiments, when referring to the shape, positional relationship, etc., of components, etc., unless otherwise specified, and in principle, it is considered that this is not clearly the case, it is substantially the same. Including those that are approximate or similar to the shape. The same applies to the above numerical values and ranges.

  In all the drawings for explaining the embodiments, the same members are denoted by the same reference symbols in principle, and the repeated explanation thereof is omitted. In order to make the drawings easy to understand, even a plan view may be hatched.

(Embodiment 1)
In an embodiment for carrying out the present invention, a substrate processing apparatus is configured as a semiconductor manufacturing apparatus that performs various processing steps included in a manufacturing method of a semiconductor device (IC or the like) as an example. In the following description, the present invention is applied to a vertical substrate processing apparatus for performing film formation processing by an epitaxial growth method, film formation processing by a CVD (Chemical Vapor Deposition) method, or oxidation processing or diffusion processing on a semiconductor substrate (semiconductor wafer). The case where the technical idea of is applied will be described. In particular, in this embodiment, a batch-type substrate processing apparatus that processes a plurality of substrates at once will be described.

<Configuration of substrate processing apparatus>
First, the substrate processing apparatus in the first embodiment will be described with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of the substrate processing apparatus according to the first embodiment. As shown in FIG. 1, the substrate processing apparatus 101 according to the first embodiment is configured to use a cassette 110 as a wafer carrier containing a plurality of wafers (semiconductor substrates) 200 made of silicon or the like. A housing 111 is provided. The casing 111 has, for example, a substantially rectangular parallelepiped shape. Hereinafter, although each member which comprises a substrate processing apparatus is demonstrated, the side surface in which the carrying in / out port of the cassette 110 is arrange | positioned among the side surfaces of the housing | casing 111 is demonstrated as a front. The position of each member in the housing 111 will be described with the direction toward the front as the front and the direction away from the front as the rear. A front maintenance port 103 serving as an opening provided for maintenance is opened below the front wall 111 a of the housing 111, and a front maintenance door 104 that opens and closes the front maintenance port 103 is a front wall of the housing 111. 111a.

  A cassette loading / unloading port (substrate container loading / unloading port) 112 is opened at the front maintenance door 104 so as to communicate between the inside and the outside of the casing 111. The cassette loading / unloading port 112 has a front shutter (substrate container loading / unloading port). It is opened and closed by an exit opening / closing mechanism 113. A cassette stage (substrate container delivery table) 114 is installed inside the casing 111 of the cassette loading / unloading port 112. The cassette 110 is loaded onto the cassette stage 114 by an in-process transfer device (not shown) and unloaded from the cassette stage 114. The cassette stage 114 is configured such that the wafer 200 in the cassette 110 is placed in a vertical posture and the wafer loading / unloading port of the cassette 110 faces upward by the in-process transfer device.

  A cassette shelf (substrate container mounting shelf) 105 is installed at a substantially central lower portion in the front-rear direction in the housing 111, and the cassette shelf 105 stores a plurality of cassettes 110 in a plurality of rows and a plurality of rows. The wafers 200 in the cassette 110 are arranged so that they can be taken in and out. The cassette shelf 105 is installed on a slide stage (horizontal movement mechanism) 106 so that it can traverse. Further, a buffer shelf (substrate container storage shelf) 107 is installed above the cassette shelf 105, and the cassette 110 is also stored in the buffer shelf 107.

  A cassette carrying device (substrate container carrying device) 118 is installed between the cassette stage 114 and the cassette shelf 105. The cassette transport device 118 includes a cassette elevator (substrate container lifting mechanism) 118a that can be moved up and down while holding the cassette 110, and a cassette transport mechanism (substrate container transport mechanism) 118b as a transport mechanism. The cassette 110 can be transported between the cassette stage 114, the cassette shelf 105, and the buffer shelf 107 by the continuous operation of the cassette elevator 118a and the cassette transport mechanism 118b.

  A wafer transfer mechanism (substrate transfer mechanism) 125 is installed behind the cassette shelf 105. The wafer transfer mechanism 125 includes a wafer transfer device (substrate transfer device) 125a capable of rotating or linearly moving the wafer 200 in the horizontal direction and a wafer transfer device elevator (substrate transfer device) for raising and lowering the wafer transfer device 125a. Mounting device lifting mechanism) 125b. As schematically shown in FIG. 1, the wafer transfer device elevator 125 b is installed at the left end of the housing 111. Through the continuous operation of the wafer transfer device elevator 125b and the wafer transfer device 125a, a tweezer (substrate holder) 125c in the wafer transfer device 125a is a susceptor that functions as a mounting portion for the wafer 200, and The wafer 200 is loaded (charged) and removed (discharged) from a susceptor in a susceptor holding mechanism (not shown).

  In addition to the susceptor holding mechanism, the substrate processing apparatus 101 according to the first embodiment also includes a susceptor moving mechanism (not shown). The susceptor moving mechanism is configured to load (charge) and unload (discharge) the susceptor 218 between the susceptor holding mechanism and the boat 217 (substrate holder).

  Next, in order to supply clean air, which is a cleaned atmosphere, into the substrate processing apparatus 101, a clean unit 134a configured by a supply fan and a dustproof filter is provided behind the buffer shelf 107. The clean unit 134 a is configured to circulate clean air inside the housing 111. In addition, a clean unit (not shown) including a supply fan and a dustproof filter is installed at the right end, which is opposite to the wafer transfer apparatus elevator 125b, so as to supply clean air. The clean air blown out from the clean unit flows through the wafer transfer device 125a and is then sucked into an exhaust device (not shown) and exhausted to the outside of the casing 111.

  On the rear side of the wafer transfer device (substrate transfer device) 125a, a pressure-resistant casing 140 having a confidential performance capable of maintaining a pressure lower than atmospheric pressure (hereinafter referred to as negative pressure) is installed. . The pressure-resistant housing 140 forms a load lock chamber (transfer chamber) 141 that is a load lock type standby chamber having a capacity capable of accommodating the boat 217.

  A wafer loading / unloading port (substrate loading / unloading port) 142 is opened on the front wall 140a of the pressure-resistant housing 140, and the wafer loading / unloading port 142 is opened and closed by a gate valve (substrate loading / unloading port opening / closing mechanism) 143. It has become. A gas supply pipe 144 for supplying an inert gas such as nitrogen gas to the load lock chamber 141 and a gas exhaust pipe (for exhausting the load lock chamber 141 to a negative pressure) on a pair of side walls of the pressure-resistant housing 140 (Not shown) are connected to each other.

  A processing furnace (reaction furnace) 202 is provided above the load lock chamber 141. The lower end of the processing furnace 202 is configured to be opened and closed by a furnace port shutter (furnace port gate valve) (furnace port opening / closing mechanism) 147.

  As schematically shown in FIG. 1, a boat elevator (supporting body lifting mechanism) 115 for lifting and lowering the boat 217 is installed in the load lock chamber 141. A seal cap 219 as a lid is horizontally installed on an arm (not shown) as a connecting tool connected to the boat elevator 115, and the seal cap 219 supports the boat 217 vertically. It is comprised so that a lower end part can be obstruct | occluded.

  The boat 217 includes a plurality of support columns (holding members), and a plurality of (for example, about 50 to 100) susceptors 218 are horizontally held in a state where their centers are aligned in the vertical direction. It is configured to be able to. Each unit configuring the substrate processing apparatus 101 is electrically connected to the controller 240, and the controller 240 is configured to control the operation of each unit configuring the substrate processing apparatus 101.

<Operation of substrate processing apparatus>
The substrate processing apparatus 101 according to the first embodiment is schematically configured as described above, and the operation thereof will be described below. In the following description, the operation of each unit constituting the substrate processing apparatus 101 is controlled by the controller 240.

  As shown in FIG. 1, the cassette loading / unloading port 112 is opened by the front shutter 113 before the cassette 110 is supplied to the cassette stage 114. Thereafter, the cassette 110 is loaded from the cassette loading / unloading port 112 and placed on the cassette stage 114. At this time, the wafer 200 placed on the cassette stage 114 is in a vertical posture, and is placed so that the wafer loading / unloading port of the cassette 110 faces upward.

  Next, the cassette 110 is picked up from the cassette stage 114 by the cassette carrying device 118, the wafer 200 in the cassette 110 is in a horizontal posture, and the wafer loading / unloading port of the cassette 110 facing the upper side of the housing 111 is a housing. It is rotated 90 ° so as to face the back of the body 111. Subsequently, the cassette 110 is automatically transported to the designated position on the cassette shelf 105 or the buffer shelf 107 by the cassette transport device 118 and delivered. That is, after the cassette 110 is temporarily stored in the buffer shelf 107, it is transferred to the cassette shelf 105 by the cassette conveying device 118 or directly conveyed to the cassette shelf 105.

  Thereafter, the slide stage 106 horizontally moves the cassette shelf 105 and positions the cassette 110 to be transferred so as to face the wafer transfer device 125a. 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. Then, the wafer 200 is mounted on the susceptor 218 in the susceptor holding mechanism.

  Hereinafter, in the susceptor holding mechanism, a state where the wafer 200 is loaded on the susceptor and a state where the wafer 200 is detached are shown. 2 is a top view showing a state in which the wafer 200 is loaded on the susceptor 218, and FIG. 3 is a cross-sectional view taken along the line AA in FIG. FIG. 4 is a cross-sectional view showing how the wafer 200 is detached from the susceptor 218.

  First, as shown in FIG. 2, the susceptor 218 has a disc shape, and has a concentric peripheral portion 218 a and a circular central portion 218 b. The disc-shaped wafer 200 is mounted on the central portion 218b of the susceptor 218. That is, the susceptor 218 has a disk shape larger than the wafer 200, and the wafer 200 is included in the central portion 218 b of the susceptor 218. Further, as shown in FIG. 3, the peripheral portion 218a of the susceptor 218 is higher than the central portion 218b of the susceptor 218, and the susceptor 218 has a boundary region between the peripheral portion 218a and the central portion 218b. A stepped portion 218c is formed. That is, the susceptor 218 has a shape in which the central portion 218b is recessed from the peripheral portion 218a, and the wafer 200 is mounted in the recessed central portion 218b. In other words, it can be said that the thickness of the central portion 218b of the susceptor 218 is smaller than the thickness of the peripheral portion 218a of the susceptor 218. As shown in FIGS. 2 and 3, a central portion 218 b of the susceptor 218 is provided with a plurality of pin holes PH, and a member MT is embedded in the pin holes PH. The susceptor 218 configured as described above is made of a conductive material (carbon or carbon graphite) whose surface is coated with silicon carbide (SiC). Preferably, the susceptor 218 may coat the surface of the conductive material with a coating material such as silicon carbide (SiC). Thereby, it can suppress that an impurity discharge | releases from an electroconductive material.

  Note that the susceptor 218 is preferably formed in a disk shape because it is easy to uniformly heat the wafer 200 in the circumferential direction, but the susceptor 218 may be formed in a plate shape in which the main surface of the susceptor 218 is formed in an ellipse. The main surface may be formed in a polygonal shape.

  In the susceptor holding mechanism, the push pin PN (see FIG. 4) is raised by the push pin lifting mechanism UDU (see FIG. 4). Subsequently, the wafer 200 is placed on the push-up pins PN by the wafer transfer device 125a. Then, the push-up pins elevating mechanism UDU lowers the push-up pins PN on which the wafer 200 is placed, so that the wafer 200 is mounted on the susceptor 218 as shown in FIG. Thereafter, the wafer transfer device 125a returns to the cassette 110 and loads the next wafer 200 into the susceptor holding mechanism.

  Next, an example in which the wafer 200 is detached from the susceptor 218 in the susceptor holding mechanism will be described. The wafer 200 is detached from the susceptor 218 after the wafer 200 is processed in the processing furnace 202, but the operation of loading and unloading the wafer 200 will be described.

  As shown in FIG. 4, the susceptor holding mechanism is provided with a push-up pin PN for pushing up the wafer 200 and a push-up pin elevating mechanism UDU for raising and lowering the push-up pin PN. First, after positioning the push-up pin PN so as to contact the member MT embedded in the pin hole PH formed in the susceptor 218 by the susceptor holding mechanism, the push-up pin PN is moved by the push-up pin lifting mechanism UDU. Raise. Then, as shown in FIG. 4, the wafer 200 is separated from the susceptor 218 together with the member MT embedded in the pin hole PH. In this way, the wafer 200 is detached from the susceptor 218. Thus, the wafer 200 can be loaded and unloaded between the tweezer (substrate holder) 125c (see FIG. 1) in the wafer transfer device 125a (see FIG. 1) and the susceptor 218. Further, from the viewpoint of reducing damage to the wafer 200 when the wafer 200 is pushed up, it is preferable to increase the area of the upper surface of the member MT that is brought into contact with the tip of the push-up pin PN. On the other hand, from the viewpoint of suppressing heat dissipation from the pin hole PH, it is preferable to reduce the opening area of the lower surface side of the susceptor 218 of the pin hole PH. Therefore, as shown in FIGS. 3 and 4, it is desirable that the member MT is formed in a flange shape and embedded in the pin hole PH.

  Next, when the wafer loading / unloading port 142 of the load lock chamber 141 whose interior is previously set at atmospheric pressure is opened by the operation of the gate valve 143, the wafer 200 is placed from the susceptor holding mechanism by the susceptor moving mechanism. The susceptor 218 (see FIG. 3) is removed. The detached susceptor 218 (see FIG. 3) is loaded into the load lock chamber 141 through the wafer loading / unloading port 142 by the susceptor moving mechanism, and the susceptor 218 is loaded into the boat 217.

  Here, a configuration in which the susceptor 218 having the wafer 200 mounted on the boat 217 is loaded will be described. FIG. 5 is a side view showing the overall structure of the boat 217. FIG. 6 is a plan view showing a state where a susceptor 218 on which a wafer 200 is mounted is loaded on a boat 217.

  First, as shown in FIG. 5, the boat 217 functions as a holding body that holds the susceptor 218. The boat 217 includes a disc-shaped bottom plate 217a, a disc-shaped top plate 217b, a bottom plate 217a, and a top plate 217b. It consists of three or four struts PR made of connected quartz. As shown in FIG. 6, each of the plurality of pillars PR is formed with a holding portion HU1 that holds a susceptor 218 as a support on which the wafer 200 is mounted. The holding portion HU1 is formed so as to protrude from each of the columns PR toward the central axis of the boat 217.

  Next, a configuration in which the susceptor 218 on which the wafer 200 is mounted is loaded from the side of the boat 217 will be described. FIG. 7 is an enlarged cross-sectional view taken along line BB in FIG. As shown in FIG. 7, the boat 217 has a plurality of columns PR extending in the extending direction of the boat 217 (vertical direction in FIG. 7), and the plurality of columns PR are equally spaced in the extending direction. Has a plurality of holding portions HU1. And this holding | maintenance part HU1 is provided in the mutually same height by the some support | pillar PR, and hold | maintains the three edge parts of the susceptor 218 by the three holding | maintenance part HU1 provided in the mutually same height, for example. Yes. Therefore, the susceptor 218 held by the three holding units HU1 is arranged to maintain a horizontal state. Specifically, as shown in FIG. 7, a susceptor 218 is mounted on each of the holding portions HU <b> 1 arranged at a predetermined interval in the extending direction on the boat 217. Therefore, a plurality of susceptors 218 are stacked on the boat 217 at predetermined intervals in the extending direction of the boat 217. As described above, the susceptor 218 is provided independently of the support column PR, and is configured so that the susceptor 218 can be loaded into the boat 217 and can be detached from the boat 217.

  After filling the susceptor 218 into the boat 217, the susceptor moving mechanism returns to the susceptor holding mechanism, and loads the susceptor 218 (see FIG. 3) on which the next wafer 200 is placed into the boat 217.

  When a predetermined number of susceptors 218 (see FIG. 3) are loaded into the boat 217, the wafer loading / unloading port 142 is closed by the gate valve 143. Thereafter, the lower end portion of the processing furnace 202 is opened by the furnace port shutter (furnace port gate valve 147). Subsequently, the seal cap 219 is raised by the boat elevator 115, and the boat 217 supported by the seal cap 219 is loaded into the processing furnace 202.

  After loading, arbitrary processing is performed on the wafer 200 in the processing furnace 202. After the wafer 200 is processed, the boat 217 is pulled out by the boat elevator 115. Further, the gate valve 143 is opened. Thereafter, the processed wafer 200 and the cassette 110 are paid out to the outside of the casing 111 by an operation generally reverse to the operation described above. As described above, the substrate processing apparatus 101 according to the first embodiment operates.

<Processing furnace configuration>
Next, the processing furnace 202 of the substrate processing apparatus 101 according to the first embodiment will be described with reference to the drawings. FIG. 8 is a schematic configuration diagram of the processing furnace 202 and the periphery of the processing furnace 202 of the substrate processing apparatus 101 in the present embodiment, and is shown as a longitudinal sectional view. FIG. 9 is a schematic configuration diagram of the processing furnace shown in FIG. 8 and is shown as a cross-sectional view.

  As shown in FIG. 8, the processing furnace 202 has an induction heating device 206 for heating by applying a high-frequency current. The induction heating device 206 is formed in a cylindrical shape, and includes an RF coil 2061 as an induction heating unit, a wall body 2062, and a cooling wall 2063. The RF coil 2061 is connected to a high frequency power source (not shown), and a high frequency current flows through the RF coil 2061 by the high frequency power source.

  The wall body 2062 is made of a metal such as a stainless material. The wall body 2062 has a cylindrical shape, and an RF coil 2061 is provided on the inner wall side. The RF coil 2061 is supported by a coil support portion (not shown). The coil support portion is supported by the wall body 2062 with a predetermined gap in the radial direction between the RF coil 2061 and the wall body 2062.

  On the outer wall side of the wall body 2062, a cooling wall 2063 is provided concentrically with the wall body 2062. An opening 2066 is formed at the center of the upper end of the wall body 2062. A duct is connected to the downstream side of the opening 2066, and a radiator 2064 as a cooling device and a blower 2065 as an exhaust device are connected to the downstream side of the duct.

  In the cooling wall 2063, for example, a cooling medium flow path is formed in almost the entire area of the cooling wall 2063 so that, for example, cooling water can flow as a cooling medium. The cooling wall 2063 is connected to a cooling medium supply unit that supplies a cooling medium (not shown) and a cooling medium discharge unit that discharges the cooling medium. By supplying the cooling medium from the cooling medium supply unit to the cooling medium flow path and discharging from the cooling medium discharge unit, the cooling wall 2063 is cooled, and the walls 2062 and 2062 are cooled by heat conduction. .

Inside the RF coil 2061, a reaction tube 205 constituting a reaction vessel concentrically with the induction heating device 206 is provided. The reaction tube 205 is made of quartz (SiO ₂ ) material as a heat-resistant material, and has a cylindrical shape (bell shape) with the upper end closed and the lower end opened. The reaction tube 205 forms a processing chamber 201. In other words, the processing chamber 201 is formed inside the reaction tube 205.

A manifold 209 is disposed below the reaction tube 205 concentrically with the reaction tube 205. The manifold 209 is made of, for example, quartz (SiO ₂ ) or stainless steel and has a cylindrical shape with an upper end and a lower end opened. The manifold 209 is provided to support the reaction tube 205. Note that an O-ring 309 as a seal member is provided between the manifold 209 and the reaction tube 205. The manifold 209 is supported by a holding body (not shown), so that the reaction tube 205 is installed vertically. In this way, a reaction vessel is formed by the reaction tube 205 and the manifold 209. Here, the manifold 209 is not particularly limited to the case where the manifold 209 is provided separately from the reaction tube 205, and the manifold 209 may not be provided individually as an integral part of the reaction tube 205.

  Inside the reaction tube 205, that is, in the processing chamber 201, wafers 200 as semiconductor substrates are aligned in multiple stages along the longitudinal direction of the inner tube in a vertical position in a horizontal posture by a boat 217 and a susceptor 218 as a derivative. It is stored in a state.

A gas supply nozzle 2321 formed of quartz (SiO ₂ ) material is provided between the reaction tube 205 and the wafer 200 in order to supply gas from the side to each wafer 200 disposed in the processing chamber 201. Has been placed. Further, below the reaction tube 205, a gas exhaust port as an exhaust unit formed of a quartz (SiO ₂ ) material that exhausts the gas that has passed through each wafer 200 disposed in the processing chamber 201 from the side. 2311 is formed.

  The gas supply nozzle 2321 is closed at the upper end, and a gas supply port 2322 as a blow-out port for blowing gas toward the wafer 200 is provided on the side wall. The gas supply port 2322 is formed toward the center of the wafer 200 disposed in the processing chamber 201. That is, as shown in FIG. 9, in this embodiment, a side blow system is used in which gas is supplied from the gas supply port 2322 arranged on the side surface side of the wafer 200 toward the wafer 200. In addition, as shown in FIG. 8, a plurality of stages of wafers 200 are placed on the boat 217. Therefore, a plurality of gas supply ports 2322 are formed in the gas supply nozzle 2321 so that the gas can be uniformly supplied to each of the plurality of wafers 200. In addition, the plurality of gas supply ports 2322 are preferably arranged at height positions between the wafers 200 in each stage.

  Outside the side wall below the reaction tube 205, there are provided a gas exhaust tube 231 as an exhaust unit communicating with the gas exhaust port 2311 and a gas supply tube 232 communicating with the gas supply nozzle 2321. The gas supply pipe 232 is a gas supply unit that supplies gas to the gas supply nozzle 2321. Note that the gas exhaust port 2311 and the gas exhaust pipe 231 may be provided not on the side wall below the reaction tube 205 but on the side wall of the manifold 209, for example. However, from the viewpoint of avoiding that hot exhaust gas circulates in the vicinity of the drive unit such as the rotation mechanism 254, it is preferable to provide the exhaust gas on the side wall below the reaction tube 205 as in the present embodiment. Further, the communication part between the gas supply nozzle 2321 and the gas supply pipe 232 may be provided not on the side wall below the reaction pipe 205 but on the side wall of the manifold 209, for example.

  The gas supply pipe 232 is divided into, for example, three on the upstream side, and a first gas supply is provided via valves 177, 178, 179 and MFCs (Mass Flow Controllers) 183, 184, 185 as gas flow rate control devices. A source 180, a second gas supply source 181, and a third gas supply source 182 are connected to the source 180, the second gas supply source 181, and the third gas supply source 182, respectively. A gas flow rate control unit 235 is electrically connected to the MFCs 183, 184, 185 and valves 177, 178, 179, and the gas flow rate control unit 235 allows the flow rate of the supplied gas to be a desired flow rate. It is controlled at the timing. The gas supply pipe 232 is further branched on the upstream side, and is connected to an inert gas supply source (not shown) via a valve (not shown) and an MFC as an inert gas flow control device.

  A vacuum exhaust device 246 such as a vacuum pump is connected to the downstream side of the gas exhaust pipe 231 via a pressure sensor (not shown) as a pressure detector and an APC (Automatic Pressure Control) valve 242 as a pressure regulator. Has been. A pressure control unit 236 is electrically connected to the pressure sensor and the APC valve 242, and the pressure control unit 236 adjusts the opening degree of the APC valve 242 based on the pressure detected by the pressure sensor. Control is performed at a desired timing so that the pressure in the processing chamber 201 becomes a desired pressure.

  A seal cap 219 is provided below the manifold 209 as a furnace port lid for hermetically closing the lower end opening of the manifold 209. The seal cap 219 is made of, for example, a metal such as stainless steel and is formed in a disk shape. On the upper surface of the seal cap 219, an O-ring 301 is provided as a seal member that contacts the lower end of the manifold 209.

  The seal cap 219 is provided with a rotation mechanism 254. A rotation shaft 255 of the rotation mechanism 254 passes through the seal cap 219 and is connected to the boat 217, and is configured to rotate the wafer 200 by rotating the boat 217.

  The seal cap 219 is configured to be moved up and down in the vertical direction by an elevating motor 248 as an elevating mechanism provided outside the processing furnace 202, so that the boat 217 can be carried into and out of the processing chamber 201. It is possible.

A cylindrical heat insulating cylinder 216 made of, for example, quartz (SiO ₂ ) as a heat resistant material is disposed at the lower part of the boat 217, and is generated by induction heating by the induction heating device 206 by the heat insulating cylinder 216. Therefore, the heat is not easily transmitted to the manifold 209 side. The heat insulating cylinder 216 may be provided integrally with the boat 217 without being provided separately from the boat 217. Further, instead of the heat insulating cylinder 216 or in addition to the heat insulating cylinder 216, a plurality of heat insulating plates may be provided in the lower part of the boat 217 or the lower part of the heat insulating cylinder 216.

  The boat 217 is preferably made of a high-purity material that does not emit contaminants in order to suppress the entry of impurities into the film during the film-forming process on the wafer 200 in the processing chamber 201. Further, when a material having a high thermal conductivity is used as the material of the boat 217, the heat insulating cylinder 216 made of quartz at the lower portion of the boat 217 is thermally deteriorated. Therefore, the material having a low thermal conductivity is desirable. . In addition, since it is better to suppress the thermal influence from the boat 217 on the wafers 200 placed on the susceptor 218, it is desirable that the material is not induction heated by the induction heating device 206. Quartz material is used as the material of the boat 217 so as to satisfy these conditions.

  A drive control unit 237 is electrically connected to the rotation mechanism 254 and the lifting motor 248, and the drive control unit 237 is controlled at a desired timing so that the rotation mechanism 254 and the lifting motor 248 perform a desired operation. It is supposed to be.

  The induction heating device 206 is provided with a spirally formed RF coil 2061 divided into a plurality of upper and lower regions (zones). For example, as shown in FIG. 8, the lower zone is divided into five zones such as an RF coil L, an RF coil CL, an RF coil C, an RF coil CU, and an RF coil U. The RF coils divided into these five zones are controlled independently.

  In the vicinity of the induction heating device 206, radiation thermometers 263 as temperature detectors for detecting the temperature in the processing chamber 201 are installed, for example, at four locations. At least one radiation thermometer 263 may be installed, but temperature controllability can be improved by installing a plurality of radiation thermometers 263.

  A temperature control unit 238 is electrically connected to the induction heating device 206 and the radiation thermometer 263, and an energization state to the induction heating device 206 is adjusted based on temperature information detected by the radiation thermometer 263. Be able to. Then, the temperature control unit 238 controls the temperature in the processing chamber 201 at a desired timing so as to obtain a desired temperature distribution.

  The blower 2065 is electrically connected to the temperature control unit 238. The temperature control unit 238 is configured to control the operation of the blower 2065 in accordance with a preset operation recipe. By operating the blower 2065, the atmosphere in the gap between the wall body 2062 and the reaction tube 205 is discharged from the opening 2066. After the atmosphere is discharged from the opening 2066, it is cooled through the radiator 2064 and discharged to the equipment downstream of the blower 2065. That is, the induction heating device 206 and the reaction tube 205 can be cooled by operating the blower 2065 based on the control by the temperature control unit 238.

  The cooling medium supply unit and the cooling medium exhaust unit connected to the cooling wall 2063 are controlled by the controller 240 at a predetermined timing so that the flow rate of the cooling medium to the cooling wall 2063 becomes a desired cooling condition. It is configured. Note that it is more desirable to provide the cooling wall 2063 because it is easier to suppress heat radiation to the outside of the processing furnace 202 and the reaction tube 205 is more easily cooled. However, the cooling condition by cooling the blower 2065 is desired. The cooling wall 2063 may not be provided as long as the cooling state can be controlled.

  In addition to the opening 2066, an explosion discharge opening and an explosion discharge opening opening / closing device 2067 that opens and closes the explosion discharge opening are provided at the upper end of the wall body 2062. When hydrogen gas and oxygen gas are mixed in the wall body 2062 and an explosion occurs, a predetermined large pressure is applied to the wall body 2062. For this reason, a part with comparatively weak intensity | strength, for example, the volt | bolt, screw, panel, etc. which form the wall body 2062, will be destroyed or scattered, and damage will increase. In order to minimize this damage, the explosion vent opening / closing device 2067 is configured to open the explosion vent and release the internal pressure above a predetermined pressure when an explosion occurs in the wall body 2062. Yes.

<Configuration around the processing furnace>
Next, the configuration around the processing furnace 202 in the first embodiment will be described with reference to FIG. A lower substrate 245 is provided on the outer surface of the load lock chamber 141 as a spare chamber. The lower substrate 245 is provided with a guide shaft 264 that fits with the lifting platform 249 and a ball screw 244 that screws with the lifting platform 249. An upper substrate 247 is provided on the upper ends of the guide shaft 264 and the ball screw 244 erected on the lower substrate 245. The ball screw 244 is rotated by an elevating motor 248 provided on the upper substrate 247. The lifting platform 249 is configured to move up and down as the ball screw 244 rotates.

  A hollow elevating shaft 250 is installed on the elevating table 249 in the vertical direction, and the connection between the elevating table 249 and the elevating shaft 250 is airtight. The elevating shaft 250 moves up and down together with the elevating table 249. The elevating shaft 250 passes through the top plate 251 of the load lock chamber 141. The through hole of the top plate 251 through which the elevating shaft 250 passes has a sufficient margin so as not to contact the elevating shaft 250. Between the load lock chamber 141 and the lifting platform 249, a bellows 265 as a stretchable hollow elastic body is provided so as to cover the periphery of the lifting shaft 250 in order to keep the load lock chamber 141 airtight. The bellows 265 has a sufficient amount of expansion and contraction that can accommodate the amount of elevation of the lifting platform 249, and the inner diameter of the bellows 265 is sufficiently larger than the outer shape of the lifting shaft 250, so that it does not come into contact with the expansion and contraction of the bellows 265. ing.

  A lifting substrate 252 is fixed horizontally to the lower end of the lifting shaft 250. A drive unit cover 253 is attached to the lower surface of the elevating substrate 252 through a seal member such as an O-ring in an airtight state. The elevating board 252 and the drive unit cover 253 constitute a drive unit storage case 256. With this configuration, the inside of the drive unit storage case 256 is isolated from the atmosphere in the load lock chamber 141.

  In addition, a rotation mechanism 254 of the boat 217 is provided inside the drive unit storage case 256, and the periphery of the rotation mechanism 254 is cooled by the cooling mechanism 257. The power supply cable 258 is led from the upper end of the lifting shaft 250 through the hollow portion of the lifting shaft 250 to the rotating mechanism 254 and connected thereto. A cooling channel 259 is formed in the cooling mechanism 257 and the seal cap 219, and a cooling water pipe 260 for supplying cooling water is connected to the cooling channel 259. It passes through the hollow part.

  By driving the elevating motor 248 and rotating the ball screw 244, the drive unit storage case 256 is raised and lowered via the elevating platform 249 and the elevating shaft 250.

  As the drive unit storage case 256 rises, the seal cap 219 provided in an airtight manner on the elevating substrate 252 closes the furnace port 161, which is an opening of the process furnace 202, and enables wafer processing. When the drive unit storage case 256 is lowered, the boat 217 is lowered together with the seal cap 219, so that the wafer 200 can be carried out to the outside.

  The gas flow rate control unit 235, the pressure control unit 236, the drive control unit 237, and the temperature control unit 238 constitute an operation unit and an input / output unit, and are electrically connected to the main control unit 239 that controls the entire substrate processing apparatus 101. It is connected. These gas flow rate control unit 235, pressure control unit 236, drive control unit 237, temperature control unit 238, and main control unit 239 are configured as a controller 240. As described above, the processing furnace 202 of the substrate processing apparatus 101 in the first embodiment and the structure around the processing furnace 202 are configured.

<Substrate processing process>
Next, substrate processing steps in the substrate manufacturing method using the substrate processing apparatus in the first embodiment will be described with reference to FIGS. In the first embodiment, as one step of a substrate processing step, a method for forming a silicon-containing film containing silicon (Si) on a substrate such as wafer 200 using an epitaxial growth method (a method for manufacturing a semiconductor device) ). In the first embodiment, a semiconductor device manufacturing method will be described as an example. However, the substrate manufacturing method disclosed in the first embodiment is not limited to the semiconductor device manufacturing method. . For example, silicon using a second conductivity type (for example, n-type) epitaxial growth method opposite to the first conductivity type on a substrate such as the wafer 200 which is a semiconductor substrate of the first conductivity type (for example, p-type). The present invention can also be applied to a method for manufacturing a solar cell in which a containing film is formed to form a pn junction.

  FIG. 10 is an explanatory diagram showing a sequence of substrate processing steps. The broken line in FIG. 10 indicates the temperature in the processing chamber 201, and the solid line in FIG. 10 indicates the pressure in the processing chamber 201. In the following description, the operation of each part constituting the substrate processing apparatus 101 according to the first embodiment is controlled by the controller 240.

  First, before the boat 217 is carried into the processing chamber 201 shown in FIG. 8, the processing chamber 201 is in a standby state (standby process in FIG. 10). The standby state refers to a state in which the boat 217 is disposed in the load lock chamber 141 immediately below the processing chamber 201 and a plurality of susceptors 218 on which the wafers 200 are mounted are loaded on the boat 217. .

  When the plurality of susceptors 218 on which the wafers 200 are placed are loaded into the boat 217, as shown in FIG. 8, the boat 217 holding the plurality of susceptors 218 includes The processing chamber 201 is loaded (boat loading) by the lifting and lowering operation of the lifting shaft 250 (boat loading step in FIG. 10). In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring. At this time, the pressure inside the processing chamber 201 is, for example, 760 Torr (= 760 × 133.3 Pa).

Subsequently, for example, N ₂ gas is supplied into the processing chamber 201 as an inert gas, and the inside of the processing furnace 202 including the processing chamber 201 is replaced with the inert gas (N ₂ purge 1 step in FIG. 10). Note that the inert gas is supplied from an inert gas supply source (not shown) connected to the gas supply pipe 232 through the plurality of gas supply ports 2322 of the gas supply nozzle 2321.

  Subsequently, the processing chamber 201 is evacuated by the evacuation device 246 so that the inside of the processing chamber 201 has a desired pressure, and the processing chamber 201 is depressurized (step 1 of evacuation in FIG. 10).

Subsequently, the pressure in the processing chamber 201 is measured by a pressure sensor, and the APC valve (pressure regulator) 242 is feedback-controlled based on the measured pressure (pressure control step in FIG. 10). At this time, as an inert gas, for example, N ₂ gas is supplied from an inert gas supply source (not shown) connected to the gas supply pipe 232 through a plurality of gas supply ports 2322 of the gas supply nozzle 2321. The By this pressure control step, the pressure inside the processing chamber 201 is adjusted to a constant pressure among the processing pressures selected from 16000 Pa to 93310 Pa. For example, 200 Torr to 700 Torr (200 × 133.3 Pa to 700 × 133.3 Pa).

Subsequently, before the film formation step (see FIG. 10), H ₂ gas as a purge gas is supplied from the gas supply nozzle 2321 into the processing chamber 201, and the gas in the processing chamber 201 is converted into the purge gas (H ₂ gas). Replace (H ₂ purge step in FIG. 10).

  Subsequently, the blower 2065 is operated, and gas or air flows between the induction heating device 206 and the reaction tube 205, and the side wall of the reaction tube 205, the gas supply nozzle 2321, the gas supply port 2322, and the gas exhaust port 2311. Is cooled. Cooling water as a cooling medium flows through the radiator 2064 and the cooling wall 2063, and the inside of the induction heating device 206 is cooled through the wall body 2062.

  Further, a high frequency current is applied to the induction heating device 206 so that the wafer 200 has a desired temperature, and an induced current (eddy current) is generated in the susceptor 218. Specifically, a plurality of susceptors 218 held in at least the boat 217 in the processing furnace 202 are induction-heated by the induction heating device 206 to heat the wafers 200 accommodated in the susceptor 218 (a temperature raising step in FIG. 10). ). That is, when a high-frequency current is passed through the induction heating device 206, a high-frequency electromagnetic field is generated inside the processing furnace 202, and an eddy current is generated in the susceptor 218 that is a derivative by the high-frequency electromagnetic field. In the susceptor 218, induction heating occurs due to eddy current, and the susceptor 218 is heated. Specifically, the eddy current is generated at the peripheral portion of the susceptor 218 that is a derivative, and the peripheral portion of the susceptor 218 is mainly heated by induction heating by the induction heating device 206. In the susceptor 218 whose peripheral portion is heated, radiant heat is generated, and the wafer 200 mounted on the susceptor 218 is heated by the radiant heat. Further, in the susceptor 218 whose peripheral portion is heated, heat flows from the peripheral portion of the susceptor 218 to the central portion of the susceptor 218 by heat conduction, and the entire susceptor 218 (peripheral portion and central portion) is heated. For this reason, when the susceptor 218 is heated, heat is transferred to the wafer 200 mounted on the susceptor 218 by heat conduction, and the wafer 200 is heated.

  As described above, the substrate processing apparatus 101 according to the first embodiment employs a method of heating the wafer 200 by the induction heating method. At this time, the amount of heating is often insufficient even if the wafer 200 is directly induction heated by a high frequency electromagnetic field generated by flowing a high frequency current through the induction heating device 206. Therefore, in this induction heating method, the susceptor 218 which is a derivative is used so that it can be efficiently heated by induction heating. That is, the induction heating type substrate processing apparatus 101 uses the susceptor 218 so as to be efficiently heated by induction heating. Then, after the susceptor 218 is efficiently heat-treated by induction heating, the wafer 200 on the heated susceptor 218 is heated by heat conduction from the susceptor 218. Therefore, the susceptor 218 has a function of mounting the wafer 200 and, as an important function thereof, has a function as a heating source that is induction-heated by a high-frequency electromagnetic field and heats the wafer 200. .

At this time, the state of energization to the induction heating device 206 is feedback-controlled based on the temperature information detected by the radiation thermometer 263 so that the inside of the processing chamber 201 has a desired temperature distribution. At this time, the blower 2065 is controlled by a preset control amount such that the temperature of the outer wall of the reaction tube 205 is cooled to, for example, 600 ° C. or lower, which is much lower than the temperature at which the film is grown on the wafer 200. The wafer 200 is heated at a constant temperature among processing temperatures selected within a range of 700 ° C. to 1200 ° C. For example, the wafer 200 is heated to 1100 to 1200 ° C. Further, for example, when SiHCl ₃ (trichlorosilane) is used as the source gas and hydrogen (H ₂ ) is used as the carrier gas, the susceptor 218 is induction-heated to 1150 ° C. or higher. In addition, the wafer 200 is heated at a constant temperature among the processing temperatures selected in the range of 700 ° C. to 1200 ° C. At this time, the blower 2065 is provided on the outer wall of the reaction tube 205 at any processing temperature. The temperature is controlled by a preset control amount so that the temperature is much lower than the temperature at which the film is grown on the wafer 200, for example, 600 ° C. or lower. Subsequently, when the boat 217 is rotated by the rotation mechanism 254, the susceptor 218 and the wafer 200 mounted on the susceptor 218 are rotated.

When the temperature of the wafer 200 (the temperature in the processing chamber 201) is stabilized, the processing gas is supplied from the first gas supply source 180, the second gas supply source 181, and the third gas supply source 182, and the wafer 200 is heated. A silicon-containing film is formed on the surface by epitaxial growth (deposition process in FIG. 10). The first gas supply source 180, the second gas supply source 181, and the third gas supply source 182 include a source gas (processing gas), a reaction gas (processing gas), and a carrier gas for generating a silicon-containing film. (Processing gas) is enclosed. For example, the silicon-containing gas as the source gas includes SiH ₄ (silane), Si ₂ H ₆ (disilane), SiH ₂ Cl ₂ (dichlorosilane), SiHCl ₃ (trichlorosilane), SiCl ₄ (silicon tetrachloride), and the like. Can be illustrated. Examples of the H-containing gas as the reaction gas include H ₂ (hydrogen), NH ₃ (ammonia), and the like. In addition to H ₂ (hydrogen), an inert gas such as Ar (argon), He (helium), or Ne (neon) can also be used as the carrier gas. In the case of using H ₂ gas as the reaction gas can be used also a carrier gas and a reactive gas. In this case, for example, the source gas is sealed in the first gas supply source 180, the carrier gas and H ₂ gas as the reaction gas are sealed in the second gas supply source 181, and the purge gas is sealed in the third gas supply source 182. H ₂ gas, Ar gas, He gas, or Ne gas is sealed. When an inert gas such as Ar (argon), He (helium), or Ne (neon) is used as the purge gas, the H ₂ purge process shown in FIG. 10 is replaced with an Ar gas purge process, a He gas purge process, or Ne. It can be read as a gas purge process. In this case, the carrier gas and the purge gas may be different from each other. The above is an example in the case of generating a silicon film, and as a modification, a silicon-containing film in which an impurity element is doped in silicon can be formed. When producing a silicon-containing film containing an impurity element, a doping gas containing the impurity element can be supplied as a second source gas together with the silicon-containing gas. In this case, for example, the gas supply pipe 232 shown in FIG. 8 is divided into four on the upstream side, a valve (not shown), a gas flow rate controller (not shown), and a fourth gas supply source ( A doping gas can be supplied by connecting (not shown). Examples of the doping gas include B ₂ H ₆ (diborane), BCl ₃ (boron trichloride), PH ₃ (phosphine), and the like.

By the way, in order to produce a silicon-containing film, a reduction reaction by hydrogen is used, but it is included in the composition of the reaction gas in a reaction that produces an intermediate product or a reaction that forms a by-product to produce silicon atoms. Use hydrogen. Although it is considered that a complicated reaction actually occurs, main reactions are exemplified below. For example, when forming a silicon film using SiCl ₄ (silicon tetrachloride) as a source gas,
SiCl ₄ + H ₂ → SiCl ₂ + 2HCl
By this reaction, HCl as a by-product and SiCl ₂ as an intermediate product are generated and adsorbed on the surface of the wafer 200 as a substrate. And
SiCl ₂ + H ₂ → Si + 2HCl
By this reaction, HCl as a by-product and Si atoms are generated, and HCl as a by-product is desorbed from the substrate to form a silicon film.

For example, when a silicon film is formed using SiHCl ₃ (trichlorosilane) as a source gas, SiCl _{2 as} an intermediate product is generated by thermal decomposition and is adsorbed on the surface of the wafer 200 as a substrate. And
SiCl ₂ + H ₂ → Si + 2HCl
By this reaction, HCl as a by-product and Si atoms are generated, and HCl as a by-product is desorbed from the substrate to form a silicon film. As described above, since the silicon-containing film is generated by utilizing the reduction reaction by hydrogen, a hydrogen-containing gas such as H ₂ (hydrogen) or NH ₃ (ammonia) containing hydrogen in the composition is used as the reaction gas.

  Further, in the film forming process, the MFCs 183, 184, After the opening of 185 is adjusted, valves 177, 178, 179 are opened. Accordingly, each processing gas flows through the gas supply pipe 232 and flows into the gas supply nozzle 2321.

  Since the cross-sectional area of the gas supply nozzle 2321 is sufficiently larger than the opening area of the plurality of gas supply ports 2322, the internal pressure is higher than that of the processing chamber 201. Therefore, the gas ejected from each gas supply port 2322 is supplied to the processing chamber 201 at a substantially uniform flow rate and flow rate. The gas supplied to the processing chamber 201 undergoes thermal decomposition or reduction reaction by hydrogen on the surfaces of the plurality of wafers 200 arranged in the processing chamber 201, and a part thereof becomes a silicon-containing film. The remaining gas is discharged to the gas exhaust port 2311 together with the by-product gas generated when the silicon-containing film is generated, and then exhausted from the gas exhaust port 2311 to the gas exhaust pipe 231. That is, the processing gas is heated from the vertically adjacent susceptors 218 when passing through the gap between the susceptors 218, contacts the heated wafer 200, and contains silicon by epitaxial growth on the surface of the wafer 200. A film is formed.

When a preset time elapses, the temperature of the processing chamber 201 is decreased (temperature decrease in FIG. 10). Then, the inside of the processing chamber 201 is evacuated by the vacuum exhaust device 246 so as to have a desired pressure, and the inside of the processing chamber 201 is depressurized (step 2 of vacuum exhausting in FIG. 10). Subsequently, for example, N ₂ gas is supplied as an inert gas from an inert gas supply source (not shown), the inside of the processing chamber 201 is replaced with the inert gas, and the pressure in the processing chamber 201 is normally maintained. The pressure is restored (N ₂ purge 2 step in FIG. 10).

  After that, the seal cap 219 is lowered by the lifting motor 248 so that the lower end of the manifold 209 is opened, and the processed wafer 200 is carried out from the lower end of the manifold 209 to the outside of the reaction tube 205 while being held by the boat 217. (Boat unloading) is performed (boat unloading step in FIG. 10). Thereafter, the processed wafer 200 is taken out from the boat 217 (wafer discharge). As described above, the wafer 200 having the silicon-containing film formed on the surface is obtained.

<Details of film formation process>
Next, a technique for reducing the consumption of processing gas in the film forming process shown in FIG. 10 will be described. FIG. 11 is an explanatory diagram showing the relationship among the flow rate of the processing gas, the temperature of the wafer, and the growth rate of the silicon-containing film in the H ₂ purge process, the temperature raising process, and the film forming process shown in FIG. FIG. 21 is an explanatory diagram showing a comparative example with respect to FIG. The source gas corresponds to the aforementioned silicon-containing gas. As the carrier gas, H ₂ gas, Ar gas, He gas, or Ne gas is used. When H ₂ gas is used as the carrier gas, the reaction gas and the carrier gas commonly become a hydrogen-containing gas, but in the following description, the hydrogen-containing gas as the reaction gas and the hydrogen-containing gas as the carrier gas In order to distinguish gas, it demonstrates using the term of source gas, reaction gas, and carrier gas.

  From the viewpoint of reducing the consumption of the processing gas, particularly the raw material gas, it is preferable to keep the growth rate (film formation rate) substantially constant in the film formation step shown in FIG. This is because by keeping the growth rate substantially constant, the utilization efficiency of the processing gas is improved and the consumption of the processing gas, particularly the raw material gas, can be reduced.

However, according to the study of the present inventor, as shown in FIG. 21, when the raw material gas and the reaction gas at a constant flow rate are continuously supplied, the growth is performed in the film generation step (ie, the step of growing the silicon-containing film). It was found that the speed decreased. For example, in FIG. 8, the processing temperature (set temperature in the processing chamber 201 in the film generation process) is 1100 ° C., the pressure in the gas supply nozzle 2321 is 80 kPa, SiHCl ₃ is the source gas, H ₂ gas is the reaction gas, and the carrier gas A case where a silicon film is formed will be described. When the partial pressure of SiHCl ₃ gas is 4 kPa, the film thickness of the silicon film is 2 μm at the time when 2 minutes have elapsed from the start of the film generation process, and at the time when 15 minutes have elapsed from the start of the film generation process. The film thickness of the silicon film was 13 μm. That is, the average growth rate for 2 minutes after the start of the film generation process is 1.00 μm / min, the average growth rate for 15 minutes after the start of the film generation process is 0.87 μm / min, and the growth rate decreases with time. You can see that

  At this time, as shown in FIG. 21, the wafer temperature also decreased with the passage of time, and it was found that the decrease in the wafer temperature is one of the factors that decrease the growth rate. In the film forming process, before reaching the wafer 200 (see FIG. 8), from the viewpoint of suppressing generation of substances generated by thermal decomposition or gas reaction around the processing chamber 201 (FIG. 8), It is preferable that the temperature be lower than the temperature of the wafer 200. However, if the raw material gas having a temperature lower than that of the wafer 200 is continuously supplied toward the wafer 200, the heat of the wafer 200 is taken and the temperature is lowered. The reduction reaction using hydrogen is an endothermic reaction, and as a result of absorbing the heat of the wafer 200 as reaction heat when forming an intermediate product or forming a silicon-containing film, the wafer The temperature of 200 decreases. The temperature drop of the wafer 200 may be detected by a temperature sensor (for example, a radiation thermometer 263 shown in FIG. 8) and immediately compensated by a heating source (for example, the RF coil 2061 and the susceptor 218 shown in FIG. 8). Until the temperature of the wafer 200 is raised again, the utilization efficiency of the processing gas is lowered. In particular, when the susceptor 218 that is an induction heating body is heated by an induction heating method as in the present embodiment, for example, the temperature control response is higher than the Joule heating method in which the wafer 200 is heated by the Joule heat of the heater. Since the speed becomes slow, the utilization efficiency of the processing gas tends to decrease.

  Therefore, in the film forming process of this embodiment (see FIG. 10), as shown in FIG. 11, the source gas and the reactive gas are supplied and discharged, and silicon is applied to the wafer 200 (see FIG. 8) which is a substrate. The film generation step S1 for forming the containing film and the re-temperature increase step S2 for stopping the supply of the source gas and the reaction gas and increasing the temperature of the wafer 200 as the substrate alternately after the film generation step S1 are alternately performed a plurality of times. carry out. That is, in the reheating step S2 shown in FIG. 11, for example, as shown in FIG. 8, the valve 177 connected to the first gas supply source 180 in which the silicon-containing gas as the source gas is sealed, and the reactive gas The temperature of the wafer 200 is raised while the valve 178 connected to the second gas supply source 181 in which the hydrogen-containing gas is sealed is closed. Thus, in the reheating step S2, by stopping the supply of the source gas and the reactive gas, the temperature of the wafer 200 whose temperature has been lowered can be increased again. Then, after the temperature of the wafer 200 has risen, the film generation step S1 is started again, so that a decrease in the growth rate can be suppressed. In the reheating step S2, the supply of the raw material gas and the reactive gas is stopped, so that the raw material gas and the reactive gas are not consumed during this time. That is, it is possible to improve the utilization efficiency of the raw material gas and the reactive gas and reduce the consumption.

  Moreover, the following effects are acquired by raising the temperature of the wafer 200 again. That is, as another problem that becomes an inhibiting factor for reducing the growth rate, there is a problem that the amount of adsorption of by-products generated during the reaction to the substrate (wafer 200) increases. For example, in the above reduction reaction using hydrogen, a by-product such as HCl is generated and adsorbed on the wafer 200 as a substrate. When the amount of such a by-product adsorbed increases, the growth rate decreases. On the other hand, in this embodiment, since the temperature of the wafer 200 is raised again in the reheating step S2, the by-product adsorbed on the wafer 200 is easily desorbed. For this reason, the fall of the growth rate resulting from adsorption | suction of a by-product can be suppressed.

  Further, in the present embodiment, as shown in FIG. 11, in the reheating step S2, the supply of the source gas and the reactive gas is stopped. At this time, the carrier gas is supplied to the wafer 200 (see FIG. 8). Supply continuously. In the reheating step S2, it is conceivable as a modified example to stop all the processing gases supplied into the processing chamber 201 from the gas supply nozzle 2321 shown in FIG. In this case, the processing gas (raw material gas, reaction gas, and carrier gas) stays in the gas supply nozzle 2321 during the reheating step S2. Since the gas supply nozzle 2321 is disposed in the processing chamber 201, the temperature of the processing gas staying in the gas supply nozzle 2321 increases. In this case, the raw material gas is thermally decomposed or reacted in the gas supply nozzle 2321, and there is a concern that the product adheres to the gas supply nozzle 2321. For this reason, it is preferable that the carrier gas is continuously supplied to the wafer 200 in the re-heating step S2. As a result, it is possible to prevent the processing gas (raw material gas, reactive gas, and carrier gas) from staying in the gas supply nozzle 2321, so that thermal decomposition or reaction of the raw material gas occurs in the gas supply nozzle 2321, and the product Can be prevented from adhering in the gas supply nozzle 2321. Thus, if the thermal decomposition of the source gas and the occurrence of reaction in the gas supply nozzle 2321 are suppressed, the amount of the processing gas that does not contribute to the formation of the silicon-containing film can be reduced. In other words, since the use efficiency of the processing gas can be improved, the consumption amount of the source gas and the reaction gas (the total amount supplied when forming the generated film) can be reduced. Further, when a product adheres to the gas supply nozzle 2321, there is a concern that the pressure balance in the gas supply nozzle 2321 is lost and the flow rate of the processing gas supplied to the wafer 200 becomes unstable. According to this, this can be suppressed.

  Further, if the carrier gas is continuously supplied to the wafer 200 in the reheating step S2, the growth rate of the source gas and the silicon-containing film causing the temperature decrease of the wafer 200 around the wafer 200 is reduced. It can suppress that the by-product which becomes a factor retains. The by-product is exhausted from the gas exhaust pipe 231 shown in FIG. 8 together with the carrier gas. For this reason, the temperature raising time of the wafer 200 in the re-temperature raising step S2 can be shortened. Further, from the viewpoint of shortening the heating time of the wafer 200, the carrier gas is preferably a gas having a specific heat smaller than that of the silicon-containing gas that is the source gas.

In the profile of the present embodiment shown in FIG. 11, an example of the result confirmed experimentally by the present inventor will be described. For example, in FIG. 8, the processing temperature (set temperature in the processing chamber 201 in the film generation process) is 1100 ° C., the pressure in the gas supply nozzle 2321 is 80 kPa, SiHCl ₃ is the source gas, H ₂ gas is the reaction gas, and the carrier gas As a result, when the film generation step S1 and the reheating step S2 shown in FIG. 11 were repeated for 2 minutes each, the total number of hours of the film generation step S1 until the film thickness of the silicon film reached 13 μm was evaluated. As a result of the experiment, the film generation step S1 was performed about 6.5 times, that is, for about 13 minutes, and thereby the film thickness of the silicon film was grown to 13 μm. Therefore, the consumption of the source gas and the reaction gas can be reduced by about 15% with respect to the result of the comparative example shown in FIG.

<Typical effects of the present embodiment>
As described above, according to the technical idea described in the present embodiment, at least one of the plurality of effects described below is produced.

  (1) According to the present embodiment, it is possible to suppress a decrease in the growth rate of the silicon-containing film by repeating the film generation step S1 and the reheating step S2 a plurality of times during the film formation step.

  (2) Further, according to the present embodiment, since the temperature of the substrate is raised again in the reheating step S2, the by-product adsorbed on the substrate is easily desorbed. For this reason, the fall of the growth rate resulting from adsorption | suction of a by-product can be suppressed.

  (3) Further, according to the present embodiment, in the reheating step S2, the supply of the raw material gas and the reactive gas is stopped by stopping the supply of the silicon-containing gas as the raw material gas and the hydrogen-containing gas as the reactive gas. Efficiency can be improved and consumption of raw material gas and reaction gas (total amount supplied when forming a production | generation film | membrane) can be reduced.

  (4) In particular, when a susceptor that is an induction heating body is heated by an induction heating method, for example, the substrate is heated by the Joule heat of the heater. Although the gas utilization efficiency tends to decrease, according to the first embodiment, the utilization efficiency of the processing gas can be improved.

  (5) Further, according to the present embodiment, since the carrier gas is continuously supplied to the substrate in the reheating step S2, the processing gas (silicon-containing gas, hydrogen-containing gas) is supplied into the gas supply nozzle 2321. ) Can be suppressed. For this reason, thermal decomposition or reaction of the silicon-containing gas occurs in the gas supply nozzle 2321, and the product can be prevented from adhering to the gas supply nozzle 2321.

  (6) Moreover, if the thermal decomposition of the silicon-containing gas in the gas supply nozzle 2321 and the occurrence of reaction can be suppressed, the utilization efficiency of the processing gas can be improved, so that the consumption of the silicon-containing gas and the hydrogen-containing gas is increased. (Total amount supplied when forming the formed film) can be reduced.

  (7) If the product adheres to the gas supply nozzle 2321, the pressure balance in the gas supply nozzle 2321 may be lost, and the flow rate of the processing gas supplied to the substrate may become unstable. According to the form 1, this can be suppressed.

  (8) If the carrier gas is continuously supplied to the substrate in the reheating step S2, the growth rate of the silicon-containing gas or the silicon-containing film that causes the temperature of the substrate to decrease around the substrate It can suppress that the by-product used as a fall factor retains. For this reason, the temperature raising time of the substrate in the reheating temperature step S2 can be shortened.

  (9) In particular, by supplying a gas having a specific heat smaller than that of the silicon-containing gas as the carrier gas, it is possible to shorten the temperature raising time of the substrate in the reheating temperature step S2.

(Embodiment 2)
In the present embodiment, an embodiment in which the heated purge gas is supplied into the processing chamber 201 in the re-heating step S2 described in the first embodiment will be described. 12 is an explanatory view showing a modification to FIG. 11, and FIG. 13 is a longitudinal sectional view showing a modification to FIG. In FIG. 13, in order to easily understand the difference from FIG. 8, the processing chamber 201 and the piping path connected to the processing chamber 201 are schematically illustrated, and the peripheral portion of the processing chamber 201 common to FIG. 8 is illustrated. Is omitted.

As shown in FIG. 12, in the present embodiment, the reheating step S2 further includes a step of supplying a heated purge gas to the wafer 200 (see FIG. 13) that is a substrate. As the purge gas, in addition to H ₂ (hydrogen), an inert gas such as Ar (argon), He (helium), Ne (neon), or the like can be used in the same manner as the carrier gas. In the reheating step S2, the heated purge gas is supplied to the wafer 200 in the processing chamber 201, so that the temperature of the wafer 200 once lowered in the film generation step S1 can be quickly raised again. For this reason, compared with the aspect shown in FIG. 11, the time of the reheating step S2 can be shortened. Alternatively, after the temperature of the wafer 200 is raised to a predetermined processing temperature in the re-heating step S2, the next film generation step S1 can be performed. Further, by supplying a purge gas in the reheating step S2, a source gas that causes a decrease in the temperature of the wafer 200 and a by-product that causes a decrease in the growth rate of the silicon-containing film from the periphery of the wafer 200 together with the purge gas. The gas can be discharged outside the processing chamber 201 through the gas exhaust pipe 231. For this reason, a decrease in the growth rate of the silicon-containing film can be more reliably suppressed. Further, from the viewpoint of positively heating the wafer 200, the purge gas flow rate is preferably larger than the raw material gas flow rate, the reactive gas flow rate, and the carrier gas flow rate, as shown in FIG. Increasing the flow rate of the purge gas can increase the rate of temperature increase of the wafer 200.

  The purge gas heating method is, for example, a method in which a purge gas heating unit such as a heater (not shown) is arranged in the purge gas supply path, or a purge gas in the processing chamber 201 as in the purge gas supply nozzle 2331 shown in FIG. The method of making the supply path longer than the supply path of the source gas and the reaction gas (gas supply nozzle 2321) can be used. In FIG. 13, a valve 188 and an MFC 187 connected to a purge gas supply source 186 filled with purge gas are provided, and these are connected to a purge gas supply nozzle 2331 which is a purge gas supply path. The MFC 187 is electrically connected to the purge gas flow rate control unit 235a of the controller 240, and the purge gas flow rate is controlled. The purge gas supply nozzle 2331 is formed separately from the gas supply nozzle 2321 that supplies a silicon-containing gas that is a raw material gas and a hydrogen-containing gas that is a reactive gas. The purge gas supply nozzle 2331 is closed at the upper end, and a purge gas supply port 2332 serving as a blow-out port for blowing gas toward the wafer 200 is provided on the side wall. The purge gas supply port 2332 is formed toward the center of the wafer 200 disposed in the processing chamber 201. In the processing chamber 201, the purge gas supply nozzle 2331 is longer than the gas supply nozzle 2321. Thus, by making the purge gas supply nozzle 2331 longer than the gas supply nozzle 2321, the purge gas is heated by, for example, radiant heat from the susceptor 218 in the supply path. Thereby, the heated purge gas can be supplied to the periphery of the wafer 200.

  Incidentally, there is a method of supplying the purge gas from the gas supply nozzle 2321 as a modification to FIG. In this case, the valve 188 and the MFC 187 connected to the purge gas supply source 186 are connected to the gas supply nozzle 2321, and a purge gas heating unit such as a heater (not shown) is disposed in the supply path to the gas supply nozzle 2321. In this case, since the purge gas flows through the gas supply nozzle 2321 in the reheating step S2, the supply of the carrier gas can be stopped. However, from the viewpoint of preventing the heated purge gas from passing through the gas supply nozzle 2321 and thereby heating the silicon-containing gas and the hydrogen-containing gas to prevent the product from adhering to the gas supply nozzle 2321, as shown in FIG. As described above, a configuration including the purge gas supply nozzle 2331 separately from the gas supply nozzle 2321 is preferable. In this case, since the purge gas can be sufficiently heated, the temperature of the wafer 200 once lowered in the film generation step S1 can be rapidly raised again.

  Further, as shown in FIG. 12, it is preferable not to supply the purge gas in the film generation step S1, but to supply the purge gas in the reheating step S2. Thereby, the consumption of purge gas can be reduced. In the film generation step S1, it is possible to prevent the silicon-containing gas that is the source gas from being diluted and the growth rate of the silicon-containing film from being lowered.

  FIG. 12 shows an example in which the carrier gas is continuously supplied in the film generation step S1 and the reheating step S2. However, as a modification, the supply of the carrier gas is stopped in the reheating step S2. You can also. In this case, a part of the raw material gas and the reactive gas stays in the gas supply nozzle 2321. However, according to the present embodiment, the time of the re-heating step S2 can be shortened, The product can be prevented from adhering in the gas supply nozzle 2321. In this case, the consumption of carrier gas can be reduced.

  Since it is the same as that of the embodiment demonstrated using FIGS. 1-11 except the said difference, the overlapping description is abbreviate | omitted.

<Typical effects of the present embodiment>
As described above, according to the technical idea described in the present embodiment, in addition to the effects described in the first embodiment, at least one of the plurality of effects described below is achieved.

  (1) According to the present embodiment, by supplying the purge gas heated to the substrate in the re-temperature raising step, the temperature of the substrate once lowered in the film generation step can be quickly raised.

  (2) In the reheating step, by supplying a purge gas, a source gas that causes a decrease in the temperature of the substrate and a by-product that causes a decrease in the growth rate of the silicon-containing film are removed from the periphery of the substrate together with the purge gas. Can do.

  (3) The purge gas consumption can be reduced by supplying the purge gas in the reheating step without supplying the purge gas in the film generation step. Further, in the film generation process, it is possible to prevent the silicon-containing gas that is the source gas from being diluted and the growth rate of the silicon-containing film from being lowered.

  (4) By providing a supply path for the purge gas separately from the supply path for the silicon-containing gas that is the source gas and the hydrogen-containing gas that is the reaction gas, the product is prevented from adhering to the source gas supply path. Can do. In addition, since the purge gas can be sufficiently heated, the temperature of the substrate once lowered in the film generation process can be rapidly raised again.

(Embodiment 3)
In the present embodiment, an embodiment will be described in which the temperature in the wafer 200 is raised by increasing the pressure in the processing chamber 201 in the re-heating step S2 described in the first embodiment. FIG. 14 is an explanatory view showing a modification to FIG. FIG. 15 is an explanatory view showing a modification to FIG. In the present embodiment, a first step of supplying a hydrogen-containing gas and a silicon-containing gas, a second step of supplying a purge gas, and a third step of containing a purge gas with a reduced exhaust amount from the processing chamber, By repeating alternately, a silicon-containing film is formed on the substrate.

  In the modification shown in FIG. 14, in the re-heating step S2, the opening of the exhaust valve is made smaller than that in the film generation step S1, and the opening of the exhaust valve is increased before the next film generation step S1. And a process of performing. In other words, the re-temperature raising step S2 of the present embodiment includes a step of discharging the gas in the processing chamber 201 from the processing chamber 201 with the first discharge amount, and the gas in the processing chamber 201 from the processing chamber 201. And a step of discharging with a second discharge amount smaller than the first discharge amount. The exhaust valve is a valve that adjusts the flow rate of the gas exhaust path in the processing chamber 201 shown in FIGS. 8 and 13, and corresponds to the APC valve 242 shown in FIGS. 8 and 13. Specifically, when the reheating step S2 is performed, the set pressure of the APC valve 242 is set higher than the set value in the film generation step S1. Then, the set pressure of the APC valve 242 is returned to the original state before the subsequent film generation step S1. Thereby, the opening degree of the exhaust valve can be adjusted, and the exhaust amount of the gas exhausted from the processing chamber 201 can be adjusted.

  As described above, in the re-heating step S2, the pressure in the processing chamber 201 (furnace pressure) increases as shown in FIG. 14 by reducing the displacement. As a result, the temperature of the wafer 200 disposed in the processing chamber 201 and once lowered in the film generation step S1 can be quickly raised again. If the exhaust amount is increased before the subsequent film generation step S1, the temperature in the processing chamber 201 can be prevented from rising excessively. For this reason, in the film production | generation process S1, the temperature of the wafer 200 can be hold | maintained substantially constant. FIG. 14 shows an example in which the exhaust valve is not closed and the exhaust is continuously performed with an exhaust amount smaller than that in the film generation step S1, but as a modified example, as shown in FIG. In addition, the exhaust valve can be closed in the reheating step S2.

  As shown in FIG. 14, in this embodiment, the purge gas is supplied to the wafer 200 after switching from the film generation step S <b> 1 to the reheating step S <b> 2. Thus, the pressure in the processing chamber 201 can be increased in a short time by reducing the amount of gas exhausted from the processing chamber 201 and supplying the purge gas in the reheating step S2. Further, from the viewpoint of efficiently increasing the pressure in the processing chamber 201, it is preferable to supply the purge gas before reducing the amount of gas exhausted from the processing chamber 201 as shown in FIG. In addition, as described with reference to FIGS. 12 and 13, the heating rate of the wafer 200 can be further increased by supplying the heated purge gas. Further, by supplying the purge gas, a silicon-containing gas having a specific heat larger than that of the purge gas can be pushed out from the periphery of the wafer 200.

  FIG. 14 shows an example in which the carrier gas is continuously supplied in the film generation step S1 and the reheating step S2. However, as a modification, the supply of the carrier gas is stopped in the reheating step S2. You can also. In this case, a part of the source gas and the reaction gas stays in the gas supply nozzle 2321 (see FIG. 8 or FIG. 13), but according to the present embodiment, the time of the reheating step S2 Therefore, it is possible to suppress the product from adhering to the gas supply nozzle 2321. In this case, the consumption of carrier gas can be reduced.

  Since it is the same as that of the embodiment demonstrated using FIGS. 1-13 except the said difference, the overlapping description is abbreviate | omitted.

<Typical effects of the present embodiment>
As described above, according to the technical idea described in the present embodiment, in addition to the effects described in the embodiment, at least one of the plurality of effects described below is achieved.

  (1) According to the present embodiment, in the reheating step, the amount of gas discharged from the processing chamber from the processing chamber is made smaller than that in the film generation step, thereby increasing the pressure in the processing chamber and The temperature can be raised quickly.

  (2) By supplying the purge gas in the reheating step, the pressure in the processing chamber can be increased in a short time.

(Embodiment 4)
In the present embodiment, another embodiment in which the temperature in the processing chamber 201 is increased to raise the temperature of the wafer 200 in the re-heating step S2 described in the first embodiment will be described. FIG. 16 is an explanatory view showing a modification to FIG. In the present embodiment, when supplying the hydrogen-containing gas and the silicon-containing gas, a first step of stopping the supply of the silicon-containing gas first, and a third step of reducing the amount of gas exhausted from the processing chamber of the processing chamber. Steps are alternately repeated to form a silicon-containing film on the substrate.

  The modification shown in FIG. 16 is different from FIG. 14 in that the supply of the reaction gas is stopped and the purge gas is not supplied in the reheating step S2. Specifically, in FIG. 16, the supply of the silicon-containing gas that is the source gas is stopped when the film generation process S1 is switched to the re-heating process S2. On the other hand, the hydrogen-containing gas that is a reactive gas is stopped after the source gas is stopped. That is, the supply time of the reaction gas is longer than the supply time of the source gas, and is stopped in the middle of the reheating step S2.

  That is, in this embodiment, the pressure in the processing chamber 201 can be increased in a short time by supplying the reaction gas at least halfway through the re-heating step S2. Further, by supplying the reaction gas, a silicon-containing gas having a specific heat larger than that of the reaction gas can be pushed out from the periphery of the wafer 200.

  Further, since the reaction gas is supplied from the same supply path as the source gas, that is, the gas supply nozzle 2321 shown in FIG. 8, as shown in FIG. 16, even if the supply of the carrier gas is stopped in the reheating step S2. Part of the source gas can be prevented from staying in the gas supply nozzle 2321. For this reason, it can suppress that a product adheres in the gas supply nozzle 2321. In addition, the timing which stops carrier gas is not limited to the aspect shown in FIG. 16, For example, it can also be set as the aspect stopped simultaneously with reaction gas. Further, as a modification of the present embodiment, the exhaust valve can be closed in the reheating step S2 as described with reference to FIG.

  Other than the above differences, the embodiment is the same as that described with reference to FIG. 14 or FIG.

<Typical effects of the present embodiment>
As described above, according to the technical idea described in the present embodiment, in addition to the effects described in the embodiment, at least one of the plurality of effects described below is achieved.

  (1) According to the present embodiment, by supplying a hydrogen-containing gas that is a reactive gas at least halfway through the re-temperature raising step, the pressure in the processing chamber is raised to quickly raise the temperature of the substrate. Can do.

  (2) Since the hydrogen-containing gas supplied at least halfway through the re-temperature raising step is supplied from the same supply path as the silicon-containing gas that is the source gas, the silicon-containing gas is contained even if the carrier gas supply is stopped in the re-temperature raising step. It can suppress that a product adheres in the supply path of gas.

(Embodiment 5)
In this embodiment, an embodiment in which the gas in the processing chamber 201 is exhausted in the reheating step S2 described in the above embodiment will be described. FIG. 17 is an explanatory view showing a modification to FIG. In the present embodiment, the first step of supplying the hydrogen-containing gas and the silicon-containing gas and the second step of stopping the supply of the hydrogen-containing gas and the silicon-containing gas and evacuating are alternately repeated to form silicon on the substrate. A containing film is formed.

  In the modification shown in FIG. 17, the gas in the processing chamber 201 is discharged in the reheating step S2. The gas discharged in the reheating step S2 includes at least the carrier gas in the processing chamber. Further, when a by-product gas is generated in the processing chamber 201 in the film generation step S1, this by-product gas is also included in the gas discharged in the re-temperature raising step S2. Further, when there are the raw material gas and the reactive gas remaining in the processing chamber 201 without being thermally decomposed or reacted in the film generation step S1, these are also included in the gas discharged in the reheating step S2. In the reheating step S2, the supply of the reaction gas and the raw material gas is stopped as shown in FIG. 17, and therefore, by exhausting the gas in the processing chamber 201 in the reheating step S2, in the periphery of the wafer 200, It is possible to suppress the retention of the source gas that causes the temperature of the wafer 200 to decrease. For this reason, the temperature of the wafer 200 can be raised faster than the embodiment shown in FIG.

  By the way, as shown in FIG. 17, in the re-heating step S2, when the carrier gas is also stopped and the purge gas is not supplied, the pressure in the processing chamber 201 may decrease. If the film generation step S1 is performed in this state, the temperature of the wafer 200 is likely to decrease. Therefore, it is preferable to increase the pressure in the processing chamber 201 and restore the temperature before starting the film generation step S1. Therefore, if the discharge from the processing chamber 201 is stopped before switching from the reheating step S2 to the film generation step S1, as the temperature inside the processing chamber 201 rises, as shown in FIG. The pressure can be raised and restored. That is, the modification shown in FIG. 17 further includes a step of discharging the gas in the processing chamber 201 from the processing chamber 201 and a step of stopping the discharging from the processing chamber 201. At this time, as a modification to FIG. 17, when the discharge from the processing chamber 201 is stopped, either or both of the carrier gas and the heated purge gas are supplied into the processing chamber 201. The internal pressure can be restored faster. As described above, when the discharge from the processing chamber 201 is temporarily stopped, in the film generation step S1, the exhausting is started again so that the pressure in the processing chamber 201 is controlled to be constant.

<Typical effects of the present embodiment>
As described above, according to the technical idea described in the present embodiment, in addition to the effects described in the embodiment, at least one of the plurality of effects described below is achieved.

  (1) According to the present embodiment, in the re-heating step, by exhausting the gas in the processing chamber, the pressure in the processing chamber can be increased and the temperature of the substrate can be increased rapidly.

  (2) Since the discharge from the processing chamber is temporarily stopped before shifting to the film generation step, the pressure in the processing chamber can be increased to restore the predetermined pressure.

(Embodiment 6)
In this embodiment, an embodiment in which a chlorine-containing gas is supplied to a substrate together with a silicon-containing gas and a hydrogen-containing gas in the film generation step S1 described in the above-described embodiment will be described. FIG. 18 is an explanatory view showing a modification to FIG. FIG. 19 is a longitudinal sectional view showing a modification to FIG.

In the modification shown in FIG. 18, a chlorine-containing gas is supplied together with the source gas and the reaction gas in the film generation step S1. In the reheating step S2, the supply of the source gas, the reaction gas, and the chlorine-containing gas is stopped. For example, as shown in FIG. 19, the chlorine-containing gas is sealed in a gas supply source 189 connected to a gas supply pipe 232. The flow rate is controlled by the MFC 190 and the valve 191 connected to the gas supply source 189, and the gas is supplied to the wafer 200 through the gas supply nozzle 2321 together with the silicon-containing gas as the source gas and the hydrogen-containing gas as the reaction gas. . As described above, when the chlorine-containing gas is supplied together with the source gas and the reaction gas in the film generation step S <b> 1, it is possible to suppress the generation material from adhering in the gas supply nozzle 2321. For this reason, the temperature of the gas supplied to the gas supply nozzle 2321 can be made higher than in the embodiment described with reference to FIGS. That is, according to the present embodiment, the temperature of the raw material gas when reaching the wafer 200 is increased, so that a decrease in the temperature of the wafer 200 can be suppressed. Therefore, a decrease in the growth rate of the silicon-containing film due to a decrease in the temperature of the wafer 200 can be suppressed. As described above, examples of the chlorine-containing gas that can prevent the generated substance from adhering to the gas supply nozzle 2321 include HCl gas (hydrochloric acid gas) and Cl ₂ gas (chlorine gas). If it is HCl gas (hydrochloric acid gas) or Cl ₂ gas (chlorine gas), as shown in FIG. 18, it is possible to suppress the product substance from adhering in the gas supply nozzle 2321 at a flow rate lower than that of the source gas. For this reason, it is possible to suppress the chlorine-containing gas from inhibiting the growth of the silicon-containing film around the wafer 200.

  However, when the chlorine-containing gas adheres to the wafer 200, there is a concern that the growth of the silicon-containing film is hindered. For this reason, as shown in FIG. 18, it is preferable to supply purge gas and remove chlorine-containing gas from the periphery of the wafer 200 (push it toward the gas exhaust pipe 231) in the reheating step S2. By supplying the purge gas, in addition to the chlorine-containing gas supplied from the gas supply source 189, the chlorine-containing gas as a by-product generated in the film generation step S1 can be removed. In the present embodiment, as described above, the gas supplied into the gas supply nozzle 2321 can be heated. Therefore, as shown in FIG. 19, the purge gas supply source 186, the valve 188 and the MFC 187 can be connected to the gas supply pipe 232 and the purge gas can be supplied from the gas supply nozzle 2321. As a modification, as shown in FIG. 13, a purge gas supply path may be provided independently.

<Typical effects of the present embodiment>
As described above, according to the technical idea described in the present embodiment, in addition to the effects described in the embodiment, at least one of the plurality of effects described below is achieved.

  (1) According to the present embodiment, by supplying the chlorine-containing gas together with the raw material gas and the reaction gas in the film generation step, it is possible to suppress the generated substance from adhering to the gas supply path. For this reason, since the temperature of the raw material gas when reaching the substrate is increased by increasing the temperature of the gas to be supplied, a decrease in the temperature of the substrate can be suppressed.

  (2) In the reheating step, the supply of the source gas, the reaction gas, and the chlorine-containing gas is stopped, and the purge gas is supplied, so that the chlorine-containing gas can be prevented from adhering to the substrate.

(Embodiment 7)
In this embodiment mode, an embodiment in which a reheating step having a different processing time is performed in the middle of the film forming step described in the above embodiment mode will be described. FIG. 20 is an explanatory view showing a modification to FIG.

  In the modification shown in FIG. 20, after repeating the film generation step S1 and the re-temperature increase step S2 a plurality of times, a re-temperature increase step S3 having a longer time than the re-temperature increase step S2 is provided, and then the film generation step S1 and The re-heating step S2 is repeated a plurality of times. When the film generation step S1 and the reheating step S2 are repeated a plurality of times, the temperature of the wafer 200 may be reduced within the period of the reheating step S2, depending on the degree of the temperature drop of the wafer 200 and the heating rate in the reheating step S2. There may be a case where the temperature does not rise to the initial processing temperature. In this case, the difference between the initial processing temperature and the temperature of the wafer 200 after the re-heating step S2 is cumulatively increased for each cycle in which the film generation step S1 and the re-heating step S2 are repeated.

  Therefore, as shown in FIG. 20, after the film generation step S1 and the reheating step S2 are repeated a plurality of times, the reheating step S3 for a longer time than the reheating step S2 is performed. That is, the temperature difference from the initial processing temperature that has become cumulatively increased is reduced by the reheating step S3. Thereby, it is possible to suppress a decrease in the growth rate of the silicon-containing film due to the temperature decrease of the wafer 200. In FIG. 20, a modification example with respect to FIG. 11 is exemplarily shown, but the present invention can be applied in combination with any one or more modification examples of FIGS. 12 and 14 to 18.

<Typical effects of the present embodiment>
As described above, according to the technical idea described in the present embodiment, in addition to the effects described in the embodiment, at least one of the plurality of effects described below is achieved.

  (1) According to the present embodiment, after the film generation step S1 and the re-temperature increase step S2 are repeated a plurality of times, the re-temperature increase step S3 having a longer time than the re-temperature increase step S2 is provided. By repeating the step S1 and the reheating step S2 a plurality of times, it is possible to suppress a decrease in the growth rate of the silicon-containing film due to a decrease in the substrate temperature.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  For example, in the above-described embodiment, the processing apparatus that heats the substrate by the induction heating method has been described as an example. However, the substrate heating method is not only the induction heating method but also the Joule heat of a heater or the like. It can also be applied to a heating method. In the above-described embodiment, a batch type processing apparatus that processes a plurality of substrates at once has been described. However, the present invention can also be applied to a single wafer processing apparatus that processes substrates one by one.

  Moreover, it can also be set as the following structures as a modification of the embodiment demonstrated by each said embodiment. For example, a first step of supplying a hydrogen-containing gas and a silicon-containing gas, a second step of supplying a purge gas, and a third step of supplying a hydrogen-containing gas are alternately repeated to form a silicon-containing film on the substrate. Can be formed. In addition, a silicon-containing film may be formed by alternately repeating a first step of supplying a hydrogen-containing gas, a second step of supplying a hydrogen-containing gas and a silicon-containing gas, and a third step of supplying a purge gas. it can. Also, a first step for supplying a hydrogen-containing gas and a silicon-containing gas, a second step for supplying a purge gas, a third step for supplying a hydrogen-containing gas and a silicon-containing gas, and a fourth step for supplying a hydrogen-containing gas. The silicon-containing film can be formed by alternately repeating the steps.

  The present invention includes at least the following embodiments.

[Appendix 1]
Supplying and discharging a hydrogen-containing gas and a silicon-containing gas to a substrate in a processing chamber, and forming a silicon-containing film on the substrate while absorbing heat from the substrate;
Stopping the supply of the hydrogen-containing gas and the silicon-containing gas and raising the temperature of the substrate;
The substrate processing method which implements alternately several times.

[Appendix 2]
The substrate processing method according to appendix 1, further comprising a step of supplying a heated purge gas to the substrate in the step of raising the temperature of the substrate.

[Appendix 3]
In the step of raising the temperature of the substrate, a step of discharging a gas in the processing chamber from the processing chamber with a first discharge amount, and a second step of discharging the gas in the processing chamber from the processing chamber to a second discharge amount smaller than the first discharge amount. The substrate processing method according to appendix 1, further comprising a step of discharging with a discharge amount.

[Appendix 4]
The substrate processing method according to supplementary note 1, wherein the step of raising the temperature of the substrate further includes a step of discharging the hydrogen-containing gas and the silicon-containing gas from the processing chamber.

[Appendix 5]
The substrate processing method according to appendix 1, further comprising a step of exhausting the gas in the processing chamber from the processing chamber and a step of stopping the exhausting from the processing chamber in the step of raising the temperature of the substrate.

[Appendix 6]
In the step of raising the temperature of the substrate, a step of supplying and discharging a heated purge gas to the substrate, a step of supplying a heated purge gas to the substrate and increasing the pressure in the processing chamber, The substrate processing method according to appendix 1, further comprising:

[Appendix 7]
Supplying and discharging a hydrogen-containing gas and a silicon-containing gas to a substrate in a processing chamber, and forming a silicon-containing film on the substrate while absorbing heat from the substrate;
A second step of stopping the supply of the hydrogen-containing gas and the silicon-containing gas and raising the temperature of the substrate;
A substrate processing method for alternately performing a plurality of times,
The substrate processing method implemented so that the temperature increase in at least 1st 2nd process of the 2nd process implemented after the 2nd time may become higher than the temperature increase in the 2nd process implemented at least 1st time.

[Appendix 8]
The substrate processing method according to appendix 7, wherein the temperature raising time in at least one second step among the second steps carried out after the second time is longer than the temperature raising time in the second step carried out for the first time.

[Appendix 9]
The temperature raising step further includes a step of supplying a heated purge gas to the substrate,
The substrate processing method according to appendix 7, wherein the temperature of the purge gas in at least one second step among the second steps performed after the second time is higher than the temperature of the purge gas in the second step performed in the first time. .

[Appendix 10]
A processing chamber for processing the substrate;
A gas supply unit for supplying a hydrogen-containing gas and a silicon-containing gas to the substrate;
A heating unit for heating at least the substrate;
Supplying and discharging the hydrogen-containing gas and the silicon-containing gas to the substrate in the processing chamber, and forming a silicon-containing film on the substrate while absorbing heat from the substrate; A control unit for controlling the gas supply unit and the heating unit so as to perform a plurality of steps of stopping the supply of the gas and the silicon-containing gas and raising the temperature of the substrate;
A substrate processing apparatus.

  The present invention can be widely used in manufacturing industries for manufacturing semiconductor devices and solar cells.

DESCRIPTION OF SYMBOLS 101 ... Substrate processing apparatus, 103 ... Front maintenance port, 104 ... Front maintenance door 105 ... Cassette shelf, 106 ... Slide stage, 107 ... Buffer shelf, 110 ... Cassette, 111 ... Housing, 111a ... Front wall, 112 ... Cassette loading Unloading port, 113 ... front shutter, 114 ... cassette stage, 115 ... boat elevator, 118 ... cassette transfer device, 118a ... cassette elevator, 118b ... cassette transfer mechanism, 125 ... wafer transfer mechanism, 125a ... wafer transfer device, 125b ... Wafer transfer device elevator, 125c ... Tweezer, 134a ... Clean unit, 140 ... Pressure-resistant housing, 140a ... Front wall, 141 ... Load lock chamber, 142 ... Wafer loading / unloading port, 143 ... Gate valve, 144 ... Gas supply pipe 147 ... Furnace gate gate 161 ... Furnace port, 177, 178, 179, 188, 191 ... Valve, 180 ... First gas supply source, 181 ... Second gas supply source, 182 ... Third gas supply source, 183, 184, 185 187, 190 ... MFC (Mass Flow Controller), 186 ... Purge gas supply source, 200 ... Wafer, 201 ... Processing chamber, 202 ... Processing furnace, 205 ... Reaction tube, 205a ... Side wall, 205b ... Lid, 206 ... Induction heating 209 ... Manifold, 216 ... Heat insulation cylinder, 217 ... Boat, 217a ... Bottom plate, 217b ... Top plate, 218 ... Susceptor, 218a ... Peripheral part, 218b ... Center part, 218c ... Step part, 219 ... Seal cap, 231 ... Gas exhaust pipe, 232 ... Gas supply pipe, 233 ... Purge gas supply section, 235 ... Gas flow control section, 235a ... Purge gas flow control section, 236 ... Pressure Force control unit, 237 ... drive control unit, 238 ... temperature control unit, 239 ... main control unit, 240 ... controller, 242 ... APC valve, 244 ... ball screw, 245 ... lower substrate, 246 ... vacuum exhaust device, 247 ... up Substrate, 248 ... Elevating motor, 249 ... Elevating platform, 250 ... Elevating shaft, 251 ... Top plate, 252 ... Elevating substrate, 253 ... Driving unit cover, 254 ... Rotating mechanism, 255 ... Rotating shaft, 256 ... Driving unit storage case, 257 ... Cooling mechanism, 258 ... Power supply cable, 259 ... Cooling flow path, 260 ... Cooling water piping, 263 ... Radiation thermometer, 264 ... Guide shaft, 265 ... Bellows, 301, 309 ... O-ring, 2061 ... RF coil, 2062 ... Wall body, 2063 ... Cooling wall, 2064 ... Radiator, 2065 ... Blower, 2066 ... Opening, 2067 ... Explosion diffusion opening / closing 2311 ... Gas exhaust port, 2321 ... Gas supply nozzle, 2321a ... First region, 2321b ... Second region, 2322 ... Gas supply port, 2331 ... Purge gas supply nozzle, 2332 ... Purge gas supply port, C, CL, CU, L, U: RF coil, HU1: holding unit, MT: member, PF: purge gas supply unit, PH: pin hole, PN ... push-up pin, PR ... prop, UDU ... push-up pin lifting mechanism

Claims (5)

Supplying and discharging a hydrogen-containing gas and a silicon-containing gas to a substrate in a processing chamber, and forming a silicon-containing film on the substrate while absorbing heat from the substrate;
Stopping the supply of the hydrogen-containing gas and the silicon-containing gas and raising the temperature of the substrate;
The substrate processing method which implements alternately several times.   The substrate processing method according to claim 1, further comprising supplying a heated purge gas to the substrate in the step of raising the temperature of the substrate.   In the step of raising the temperature of the substrate, a step of discharging a gas in the processing chamber from the processing chamber with a first discharge amount, and a second step of discharging the gas in the processing chamber from the processing chamber to a second discharge amount smaller than the first discharge amount. The substrate processing method according to claim 1, further comprising a step of discharging with a discharge amount. Supplying and discharging a hydrogen-containing gas and a silicon-containing gas to a substrate in a processing chamber, and forming a silicon-containing film on the substrate while absorbing heat from the substrate;
A second step of stopping the supply of the hydrogen-containing gas and the silicon-containing gas and raising the temperature of the substrate;
A substrate processing method for alternately performing a plurality of times,
The substrate processing method implemented so that the temperature increase in at least 1st 2nd process of the 2nd process implemented after the 2nd time may become higher than the temperature increase in the 2nd process implemented at least 1st time. A processing chamber for processing the substrate;
A gas supply unit for supplying a hydrogen-containing gas and a silicon-containing gas to the substrate;
A heating unit for heating at least the substrate;
Supplying and discharging the hydrogen-containing gas and the silicon-containing gas to the substrate in the processing chamber, and forming a silicon-containing film on the substrate while absorbing heat from the substrate; A control unit for controlling the gas supply unit and the heating unit so as to perform a plurality of steps of stopping the supply of the gas and the silicon-containing gas and raising the temperature of the substrate;
A substrate processing apparatus.

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