JP2012067328A - Method for manufacturing semiconductor device, and substrate treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the partial pressure of a material gas supplied in a treatment chamber in a short time to increase a film formation speed of a thin film.SOLUTION: This method for manufacturing a semiconductor device includes processes of: filling a material gas in a second gas reservoir part formed in a gas supply pipe on the downstream side of a first gas reservoir part while filling an inert gas in the first gas reservoir part formed in a gas supply pipe connected to a treatment chamber; and pumping the material gas filled in the second gas reservoir part into the treatment chamber by the inert gas filled in the first gas reservoir part by respectively opening an on-off valve arranged in the gas supply pipe between the first gas reservoir part and the second gas reservoir part and an on-off valve arranged in the gas supply pipe between the second gas reservoir part and the treatment chamber.

Description

  The present invention relates to a semiconductor device manufacturing method and a substrate processing apparatus for forming a thin film on a substrate.

  As one step of manufacturing a semiconductor device such as a DRAM, a substrate processing step of forming a thin film such as a titanium nitride (TiN) film on a substrate such as a silicon wafer may be performed. In recent years, the ALD (Atomic Layer Deposition) method has come to be used as a method for forming a thin film. The ALD method is a method of forming a thin film with a desired film thickness on a substrate by alternately supplying a source gas and a reaction gas into a processing chamber in which the substrate is accommodated a predetermined number of times. When the ALD method is used, a good film quality can be obtained at a low temperature and high film thickness uniformity can be obtained as compared with the case where the CVD (Chemical Vapor Deposition) method is used.

  However, the ALD method tends to decrease the film formation rate as compared with the CVD method. In order to increase the deposition rate by the ALD method, it is effective to increase the partial pressure of the source gas supplied into the processing chamber in a short time. In order to increase the partial pressure of the raw material gas in a short time, a supply tank is provided in the gas supply pipe for supplying the raw material gas into the processing chamber, and the raw material gas is filled in the supply tank to be in a pressurized state and pressurized. It is effective to introduce the raw material gas in the supply tank into the processing chamber in a short time using the pressure difference between the supply tank and the reduced processing chamber.

  However, when the vapor pressure of the raw material gas is low, since the raw material gas may be liquefied by pressurization, it is difficult to sufficiently increase the pressure in the supply tank. It is possible to suppress liquefaction of the source gas by heating the inside of the supply tank. However, since the source gas may be thermally decomposed by heating, it has been difficult to sufficiently raise the temperature in the supply tank.

  A main object of the present invention is to provide a semiconductor device manufacturing method and a substrate processing apparatus capable of increasing a partial pressure of a source gas supplied into a processing chamber in a short time and increasing a film forming speed of a thin film. is there.

  According to one aspect of the present invention, the first gas reservoir provided in the gas supply pipe connected to the processing chamber is filled with an inert gas, and the downstream of the first gas reservoir is provided. A step of filling a source gas in a second gas reservoir provided in the gas supply pipe, and an opening / closing provided in the gas supply pipe between the first gas reservoir and the second gas reservoir. A valve and an on-off valve provided in the gas supply pipe between the second gas reservoir and the processing chamber, respectively, and an inert gas filled in the first gas reservoir, And a step of pumping the source gas filled in the second gas reservoir into the processing chamber.

According to another aspect of the present invention, the step of transporting the substrate into the processing chamber, the first on-off valve provided in the gas supply pipe connected to the processing chamber is opened and the second on-off valve is closed, The first gas reservoir provided in the gas supply pipe between the first on-off valve and the second on-off valve is filled with an inert gas, and is further downstream than the second on-off valve. The third on-off valve provided in the gas supply pipe is opened and the fourth on-off valve is closed, and provided on the gas supply pipe between the third on-off valve and the fourth on-off valve. The first on-off valve and the third on-off valve are closed with the first step of filling the second gas reservoir with the source gas, and the second on-off valve and the fourth on-off valve being closed, respectively. A second step of closing each of the valves, and each of the second on-off valve, the third on-off valve, and the fourth on-off valve. A third step of opening and feeding the source gas filled in the second gas reservoir into the processing chamber by the inert gas filled in the first gas reservoir; and the fourth on-off valve A fourth step of closing the third on-off valve in the opened state to remove residual gas in the second gas reservoir, and a step of transporting the substrate from the processing chamber, A method of manufacturing a semiconductor device is provided in which a thin film is formed on the substrate by performing the first to fourth steps a predetermined number of times.

  According to another aspect of the present invention, a processing chamber that accommodates a substrate, a gas supply system that supplies an inert gas and a source gas into the processing chamber, an exhaust system that exhausts an atmosphere in the processing chamber, and the gas A control unit that controls a supply system and the exhaust system, and the gas supply system includes a first gas supply pipe connected to the processing chamber, and the first gas supply pipe includes: In order from the upstream side, an inert gas supply source, a first on-off valve, a first gas reservoir, a second on-off valve, a third on-off valve, a second gas reservoir, and a fourth on-off valve are provided. A second gas supply pipe is connected to the first gas supply pipe between the second on-off valve and the third on-off valve, and an upstream is connected to the second gas supply pipe. A substrate processing apparatus provided with a source gas supply source and a fifth on-off valve in this order is provided.

  According to the method for manufacturing a semiconductor device and the substrate processing apparatus according to the present invention, it is possible to increase the partial pressure of the source gas supplied into the processing chamber in a short time and increase the deposition rate of the thin film.

1 is a perspective view showing a schematic configuration of a substrate processing apparatus suitably used in an embodiment of the present invention. It is a schematic block diagram of an example of the processing furnace suitably used in one embodiment of the present invention and the members accompanying it, and is a view showing the processing furnace part in particular in a longitudinal section. It is the sectional view on the AA line of the processing furnace shown in FIG. 2 used suitably in one Embodiment of this invention. It is a flowchart of the substrate processing process which concerns on one Embodiment of this invention. Titanium tetrachloride according to an embodiment of the present invention is a schematic diagram showing a valve opening and closing sequence of (TiCl ₄₎ gas supply step. It is a graph showing a vapor pressure curve of the TiCl ₄ gas as a source gas.

<One Embodiment of the Present Invention>
Hereinafter, a basic configuration of the substrate processing apparatus according to the present embodiment and a substrate processing process performed by the substrate processing apparatus will be described.

(1) Configuration of Substrate Processing Apparatus FIG. 1 is a schematic configuration diagram illustrating the overall configuration of a substrate processing apparatus 101 according to this embodiment. As shown in FIG. 1, the substrate processing apparatus 101 includes a housing 111. In order to transfer the wafer 200 as a substrate made of silicon or the like into or out of the casing 111, a cassette 110 as a wafer carrier (substrate transfer container) capable of storing a plurality of wafers 200 is used. A front maintenance port (not shown) is opened below the front wall 111a of the casing 111 as an opening that is opened so that the inside of the casing 111 can be maintained. A front maintenance door (not shown) for opening and closing the front maintenance port is provided on the front wall 111a of the housing 111. The maintenance door has a cassette loading / unloading port (substrate container loading / unloading port) 1
12 is established to communicate between the inside and outside of the casing 111. The cassette loading / unloading port 112 is opened and closed by a front shutter (substrate container loading / unloading 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 carried onto the cassette stage 114 by an in-process carrying device (not shown), and is carried out from the cassette stage 114.

  The cassette 110 is placed on the cassette stage 114 by an in-process transfer device (not shown) so that the wafers 200 in the cassette 110 are in a vertical posture and the wafer loading / unloading port of the cassette 110 faces upward. The cassette stage 114 rotates the cassette 110 90 degrees in the vertical direction toward the rear of the casing 111 to bring the wafer 200 in the cassette 110 into a horizontal posture, and the wafer loading / unloading port of the cassette 110 is placed behind the casing 111. It is configured to be able to face.

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

  A cassette 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) as a transport mechanism that can move horizontally while holding the cassette 110. 118b. The cassette 110 is transported between the cassette stage 114, the cassette shelf 105, and the spare cassette 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 that can rotate or linearly move the wafer 200 in the horizontal direction, and a wafer transfer device elevator (substrate transfer device) that moves the wafer transfer device 125a up and down. Elevating mechanism) 125b. The wafer transfer device 125a includes a tweezer (substrate transfer jig) 125c that holds the wafer 200 in a horizontal posture. Wafer transfer device elevator 125b is installed at the right end of casing 111 having pressure resistance. By continuous operation of the wafer transfer device 125a and the wafer transfer device elevator 125b, the wafer 200 is picked up from the cassette 110 on the transfer shelf 123 and loaded (charged) into a boat (substrate support member) 220 described later. Or the wafer 200 is detached from the boat 220 (discharged) and stored in the cassette 110 on the transfer shelf 123.

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

Below the processing furnace 202, a boat elevator (substrate holder lifting mechanism) 115 is provided as a lifting mechanism that lifts and lowers the boat 220 and conveys the boat 220 into and out of the processing furnace 202. The elevator 128 of the boat elevator 115 is provided with an arm 128 as a connecting tool. On the arm 128, there is a seal cap 219 which is a lid as a vacuum hermetic plate that supports the boat 220 vertically and hermetically closes the lower end of the processing furnace 202 when the boat 220 is raised by the boat elevator 115. It is provided horizontally.

  The boat 220 is configured to hold a plurality of (for example, about 10 to 150) wafers 200 in a horizontal posture and stacked in multiple stages at predetermined intervals. The configuration of the boat 220 will be described later.

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

  In addition, a clean unit 134b including a supply fan and a dustproof filter is installed at the left end of the casing 111 that is opposite to the wafer transfer device elevator 125b and the boat elevator 115 side. The clean air blown out from the clean unit 134 b flows around the wafer transfer device 125 a and the boat 220, and then is sucked into an exhaust device (not shown) and exhausted outside the housing 111.

  Next, the operation of the substrate processing apparatus 101 according to this embodiment will be described.

  The cassette loading / unloading port 112 is opened by the front shutter 113, and the cassette 110 is placed on the cassette stage 114. Thereafter, the cassette 110 is carried into the housing 111 from the cassette carry-in / out port 112. The cassette 110 is placed on the cassette stage 114 so that the wafer 200 is in a vertical posture and the wafer loading / unloading port of the cassette 110 faces upward. Thereafter, the cassette 110 is rotated 90 ° in the vertical direction toward the rear of the casing 111 by the cassette stage 114. As a result, the wafer 200 in the cassette 110 assumes a horizontal posture, and the wafer loading / unloading port of the cassette 110 faces rearward in the housing 111.

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

  When the cassette 110 is transferred to the transfer shelf 123, the wafer 200 is picked up from the cassette 110 through the wafer loading / unloading port by the tweezer 125c of the wafer transfer device 125a, and the wafer transfer device 125a and the wafer transfer device elevator 125b are picked up. Are loaded (charged) into the boat 220 provided behind the transfer chamber 124. The wafer transfer device 125 a that has transferred the wafer 200 to the boat 220 returns to the cassette 110 and loads the next wafer 200 into the boat 220.

  When a predetermined number of wafers 200 are loaded into the boat 220, the lower end of the processing furnace 202 closed by the furnace port shutter 147 is opened by the furnace port shutter 147. Subsequently, when the seal cap 219 is raised by the boat elevator 115, the boat 220 holding the group of wafers 200 is loaded into the processing furnace 202 (boat loading).

  After loading, arbitrary processing is performed on the wafer 200 in the processing furnace 202. Such processing will be described later. After the processing, the wafer 200 and the cassette 110 are discharged to the outside of the casing 111 by a procedure reverse to the above procedure in the reverse procedure.

(2) Configuration of Processing Furnace Next, the configuration of the processing furnace 202 according to one embodiment of the present invention will be described with reference to the drawings. FIG. 2 is a schematic configuration diagram of an example of a processing furnace 202 suitably used in the present embodiment and members accompanying the processing furnace 202. In particular, FIG. 2 is a view showing a portion of the processing furnace 202 in a longitudinal section. FIG. 3 is a cross-sectional view taken along line AA of the processing furnace 202 shown in FIG. 2 that is preferably used in the present embodiment.

(Processing room)
A processing furnace 202 according to an embodiment of the present invention includes a reaction tube 203 and a manifold 209. The reaction tube 203 is made of a heat-resistant non-metallic material such as quartz (SiO ₂ ) or silicon carbide (SiC), and has a cylindrical shape with the upper end closed and the lower end open. The manifold 209 is made of, for example, a metal material such as SUS, and is formed in a cylindrical shape having an open upper end and a lower end. The reaction tube 203 is supported vertically from the lower end side by the manifold 209. The reaction tube 203 and the manifold 209 are arranged concentrically. A sealing member 220 such as an O-ring is provided between the reaction tube 203 and the manifold 209. The lower end of the manifold 209 is configured to be hermetically sealed by a seal cap 219 when the above-described boat elevator 115 is raised. Between the lower end of the manifold 209 and the seal cap 219, a sealing member 220b such as an O-ring that hermetically seals the inside of the processing chamber 201 is provided.

  Inside the reaction tube 203 and the manifold 209, a processing chamber 201 for accommodating a wafer 200 as a substrate is formed. A boat 217 as a substrate holder is inserted into the processing chamber 201 from below. The inner diameters of the reaction tube 203 and the manifold 209 are configured to be larger than the maximum outer shape of the boat 217 loaded with the wafers 200.

  The boat 217 is configured to hold a plurality of (for example, 75 to 100) wafers 200 in multiple stages with a predetermined gap (substrate pitch interval) in a substantially horizontal state. The boat 217 is mounted on a heat insulating cap 218 that blocks heat conduction from the boat 217. The heat insulating cap 218 is supported from below by the rotating shaft 255. The rotation shaft 255 is provided so as to penetrate the center portion of the seal cap 219 while maintaining airtightness in the processing chamber 201. A rotation mechanism 267 that rotates the rotation shaft 255 is provided below the seal cap 219. By rotating the rotation shaft 255 by the rotation mechanism 267, the boat 217 on which the plurality of wafers 200 are mounted can be rotated while maintaining the airtightness in the processing chamber 201.

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

(Raw gas supply system)
On the side wall of the manifold 209, a source gas nozzle 400a is provided as a source gas introduction part. The source gas nozzle 400a is configured in an L shape having a vertical portion and a horizontal portion. The vertical portion of the source gas nozzle 400 a is arranged in the vertical direction along the inner wall of the reaction tube 203. A plurality of source gas supply holes 401a are provided in the vertical direction on the side surface of the vertical portion of the source gas nozzle 400a. The opening diameter of the source gas supply hole 401a may be the same from the lower part to the upper part, or may be gradually increased from the lower part to the upper part. The horizontal portion of the source gas nozzle 400 a is provided so as to penetrate the side wall of the manifold 209.

The downstream end of the first gas supply pipe 410a is connected to the upstream end of the source gas nozzle 400a protruding from the side wall of the manifold 209. The first gas supply pipe 410a includes, in order from the upstream side, an N ₂ gas tank 411a as an inert gas supply source for supplying nitrogen (N ₂ ) gas as an inert gas, a mass flow controller 412a as a flow control device, A first valve 413a as a first on-off valve, a first filling tank 414a as a first gas reservoir, a second valve 415a as a second on-off valve, a third valve 416a as a third on-off valve, A second filling tank 417a as a second gas reservoir and a fourth valve 418a as a fourth on-off valve are provided. The first filling tank 414a and the second filling tank 418a include heaters (not shown) that raise the temperature in the first filling tank 414a and the second filling tank 418a to a predetermined temperature, respectively. The first filling tank 414a and the second filling tank 418a are each provided with a pressure sensor (not shown) that measures the pressure in the first filling tank 414a and the second filling tank 418a.

The downstream end of the second gas supply pipe 410c is connected to the first gas supply pipe 410a between the second valve 413a and the third valve 415a. The second gas supply pipe 410c includes, in order from the upstream side, a liquid raw material tank 411c that supplies titanium tetrachloride (TiCl ₄ ) as a liquid raw material that is liquid at room temperature, a liquid mass flow controller 412c as a flow control device, A sixth valve 413c as a sixth on-off valve, a carburetor 414c, and a fifth valve 415c as a fifth on-off valve are provided.

The vaporizer 414c is connected to the downstream end of an inert gas supply pipe 410f that supplies an inert gas as a carrier gas for vaporizing the liquid TiCl ₄ supplied into the vaporizer 414c. The inert gas supply pipe 410f is provided with an Ar gas tank 411f for supplying Ar gas as an inert gas, a mass flow controller 412f, and a seventh valve 413f as a seventh on-off valve in order from the upstream side. The sixth valve 413c is opened, and the seventh valve 413f is opened while Ar gas whose flow rate is controlled by the mass flow controller 412f is vaporized while supplying the liquid TiCl ₄ whose flow rate is controlled by the liquid mass flow controller 412c into the vaporizer 414c. By supplying it into 414c, it is possible to generate TiCl ₄ gas as a source gas by bubbling.

  The upstream end of the vent gas pipe 410d is connected to the second gas supply pipe 410c between the vaporizer 414c and the fifth valve. The downstream end of the vent gas pipe 410d is connected to the downstream side of the APC valve 243c of the exhaust pipe 231 described later. The vent gas pipe 410d is provided with an eighth valve 411d as an eighth on-off valve.

  The raw material gas supply source according to this embodiment is mainly configured by the liquid raw material tank 411c, the liquid mass flow controller 412c, the vaporizer 414c, the inert gas supply pipe 410f, the Ar gas tank 411f, the mass flow controller 412f, and the seventh valve 413f. ing. The source gas supply source is not limited to the case of using a vaporizer that vaporizes the liquid source by bubbling as described above, and may be a case of using a vaporizer that raises the temperature of the liquid source and vaporizes, for example.

Further, mainly, the source gas nozzle 400a, the source gas supply hole 401a, the first gas supply pipe 410a, the N ₂ gas tank 411a, the mass flow controller 412a, the first valve 413a, the first filling tank 414a, the second valve 415a, and the third valve The source gas supply system according to this embodiment is configured by 416a, the second filling tank 417a, the fourth valve 418a, the second gas supply pipe 410c, the fifth valve 415c, and the source gas supply source described above.

(Reactive gas supply system)
A reaction gas nozzle 400b as a reaction gas introduction part is provided on the side wall of the manifold 209. Similar to the source gas nozzle 400a, the reactive gas nozzle 400b is configured in an L shape having a vertical portion and a horizontal portion. The vertical part of the reaction gas nozzle 400 b is arranged in the vertical direction so as to follow the inner wall of the reaction tube 203. A plurality of reaction gas supply holes 401b are provided in the vertical direction on the side surface of the vertical portion of the reaction gas nozzle 400b. The reaction gas supply holes 401b may have the same opening diameter from the lower part to the upper part, or may gradually increase from the lower part to the upper part. The horizontal part of the reactive gas nozzle 400 b is provided so as to penetrate the side wall of the manifold 209.

The downstream end of the third gas supply pipe 410b is connected to the upstream end of the reactive gas nozzle 400b protruding from the side wall of the manifold 209. In the third gas supply pipe 410b, in order from the upstream side, an NH ₃ gas tank 411b as a reaction gas supply source for supplying ammonia (NH ₃ ) gas, which is a nitriding gas as a reaction gas, a mass flow controller 412b, and a ninth A ninth valve 413b is provided as an on-off valve.

A downstream end of an inert gas supply pipe 410d for supplying an inert gas as a carrier gas or a purge gas is connected to the third gas supply pipe 410b on the downstream side of the ninth valve 413b. The inert gas supply pipe 410d has an N ₂ gas tank 411d as an inert gas supply source for supplying nitrogen (N ₂ ) gas as an inert gas, a mass flow controller 412d, and a tenth on-off valve in order from the upstream side. The tenth valve 413d is provided.

Mainly, the reactive gas nozzle 400b, the reactive gas supply hole 401b, the third gas supply pipe 410b, the NH ₃ gas tank 411b, the mass flow controller 412b, the ninth valve 413b, the inert gas supply pipe 410d, the N ₂ gas tank 411d, the mass flow controller 412d. In addition, the reactive gas supply system according to the present embodiment is configured by the tenth valve 413d.

(Exhaust system)
An upstream end of an exhaust pipe 231 that exhausts the atmosphere in the processing chamber 201 is connected to the side wall of the manifold 209. The exhaust pipe 231 is provided with a pressure sensor 245 as a pressure detector, an APC (Auto Pressure Controller) valve 243 as a pressure regulator, and a vacuum pump 246 as a vacuum exhaust device in order from the upstream side. The inside of the processing chamber 201 can be set to a desired pressure by adjusting the opening degree of the opening / closing valve of the APC valve 242 while operating the vacuum pump 246.

  The exhaust system according to this embodiment is mainly configured by the exhaust pipe 231, the pressure sensor 245, the APC valve 243, and the vacuum pump 246.

(Seal cap)
Below the manifold 209, a seal cap 219 is provided as a furnace port lid that can airtightly close the lower end opening of the manifold 209. The seal cap 219 is brought into contact with the lower end of the manifold 209 from the lower side in the vertical direction. The seal cap 219 is made of a metal such as stainless steel and has a disk shape. On the upper surface of the seal cap 219, an O-ring 220b is provided as a seal member that comes into contact with the lower end of the manifold 209. A rotation mechanism 267 that rotates the boat 217 is installed on the side of the seal cap 219 opposite to the processing chamber 201. A rotation shaft 255 of the rotation mechanism 267 passes through the seal cap 219 and supports the boat 217 from below, and is configured such that the wafer 200 can be rotated by operating the rotation mechanism 267. The seal cap 219 is configured to be lifted vertically by a boat elevator 115 as a lifting mechanism vertically disposed outside the reaction tube 203, thereby transporting the boat 217 into and out of the processing chamber 201. It is possible.

(controller)
A controller 280 as a control unit (control means) includes a heater 207 and an APC valve 243.
, Vacuum pump 246, rotation mechanism 267, boat elevator 115, first valve 413a, second valve 415a, third valve 416a, fourth valve 418a, fifth valve 415c, sixth valve 413c, seventh valve 413f, eighth The valve 410e, the ninth valve 413b, the tenth valve 413d, the liquid mass flow controller 412c, the mass flow controllers 412a, 412f, 412b, and 412d are connected. The controller 280 adjusts the temperature of the heater 207, opens / closes the APC valve 243 and adjusts the pressure, starts / stops the vacuum pump 246, adjusts the rotation speed of the rotating mechanism 267, raises / lowers the boat elevator 115, the first valve 413a, 2 valve 415a, 3rd valve 416a, 4th valve 418a, 5th valve 415c, 6th valve 413c, 7th valve 413f, 8th valve 410e, opening and closing operation of 9th valve 413b, liquid mass flow controller 412c, mass flow controller 412a , 412f, 412b, and 412d are controlled.

(3) Substrate Processing Step Next, the substrate processing step as one embodiment of the present invention will be described mainly with reference to FIGS. FIG. 4 is a flowchart of the substrate processing process according to the present embodiment. FIG. 5 is a schematic diagram showing a valve opening / closing sequence in the titanium tetrachloride (TiCl ₄ ) gas supply step according to the present embodiment.

  The present embodiment is a method of forming a titanium nitride (TiN) film on the surface of the wafer 200 by using an ALD method which is one of CVD (Chemical Vapor Deposition) methods, and a semiconductor device manufacturing process. It is implemented as one step. In the case of the CVD method, a plurality of types of gases including a plurality of elements constituting the film to be formed are simultaneously supplied. In the case of the ALD method, a plurality of types of gases including a plurality of elements constituting the film to be formed are alternately supplied. Supply. And a film | membrane is formed by controlling supply conditions, such as a gas supply flow rate at the time of gas supply, gas supply time, and plasma power. In these techniques, for example, when a TiN film is formed, the supply conditions are controlled for the purpose of setting the composition ratio of the film to be the stoichiometric composition N / Ti≈1.0. On the other hand, it is possible to control the supply conditions for the purpose of setting the composition ratio of the film to be formed to a predetermined composition ratio different from the stoichiometric composition. That is, it is also possible to control the supply conditions for the purpose of making at least one of the plurality of elements constituting the film to be formed more excessive than the other elements with respect to the stoichiometric composition. . In this manner, film formation can be performed while controlling the ratio of a plurality of elements constituting the film to be formed, that is, the composition ratio of the film. Hereinafter, a sequence example in which a plurality of types of gases including different types of elements are alternately supplied to form a film having a stoichiometric composition will be described. In the following description, the operation of each part constituting the substrate processing apparatus 101 is controlled by the controller 280.

(Wafer carry-in process (S10))
The wafer 200 to be processed is loaded into the boat 217 by the procedure described above. Subsequently, the boat elevator 115 is raised, the boat 217 loaded with the wafers 200 is carried into the processing chamber 201, and the inside of the processing chamber 201 is hermetically sealed with a seal cap 219. After the wafer 200 is loaded, the wafer 200 is rotated by the rotation mechanism.

In the wafer carry-in step (S10), the tenth valve 413d is opened with the fourth valve 418a and the ninth valve 413b closed, and N ₂ gas as the purge gas is supplied to the inert gas supply pipe 410d and the third gas. It is preferable to always flow into the processing chamber 201 through the gas supply pipe 410b and the reaction gas nozzle 400b. As a result, the oxygen (O ₂ ) concentration in the processing chamber 201 can be lowered, and adhesion of particles (foreign matter) and metal contaminants to the wafer 200 can be suppressed. Further, it is preferable that the temperature in the processing chamber 201 is raised in advance to, for example, 300 ° C.

(Decompression and temperature raising step (S20))
The inside of the processing chamber 201 is evacuated by closing the tenth valve 413d and opening the APC valve 243 with the vacuum pump 246 activated. At this time, by closing the third valve 416a and opening the fourth valve 418a, the inside of the second filling tank 417a is also exhausted. Then, the pressure in the processing chamber 201 is controlled to be a predetermined pressure by adjusting the opening degree of the APC valve 243. Further, by supplying electric power to the heater 207, the temperature in the processing chamber 201 is raised to a predetermined temperature.

Further, before starting a TiN film forming step (S30) described later, TiCl ₄ gas as a source gas is generated in advance. That is, the sixth valve 413c is opened, and the liquid TiCl ₄ whose flow rate is controlled by the liquid mass flow controller 412c is supplied into the vaporizer 414c, while the seventh valve 413f is opened and the Ar gas whose flow rate is controlled by the mass flow controller 412f is supplied. By supplying it into the vaporizer 414c, generation of TiCl ₄ gas as a raw material gas is started in advance. The generated TiCl ₄ gas is discharged to the exhaust pipe 231 through the vent gas pipe 410d without being supplied into the second filling tank 417a by opening the eighth valve 411e with the fifth valve 415c closed. The thereby produced a TiCl ₄ gas stably takes a predetermined time, before starting the TiN film formation step (S30) in advance produce a TiCl ₄ gas, the fifth valve 415c and the eighth valve 411e if so as to control the destination of the TiCl ₄ gas by switching, you can start the supply of the TiCl ₄ gas into the second filling tank 417a quickly.

In addition, before the TiN film forming step (S30) described later is started, the temperature inside the first filling tank 414a and the inside of the second filling tank 418a is raised to a predetermined temperature. By doing in this way, when the 1st process (S31a) mentioned below is carried out, gas pressure is reduced, preventing liquefaction of the gas with which it fills in the 1st filling tank 414a and the 2nd filling tank 418a. It can be raised sufficiently. The pressure in the first filling tank 414a and the second filling tank 417a needs to be a temperature at which the gas to be filled does not liquefy, that is, a pressure equal to or lower than the vapor pressure of the gas to be filled. By raising the temperature in the tank 418a from 293K (20 ° C.) to 333K (60 ° C.), the vapor pressure of the TiCl ₄ gas filled in the second filling tank 418a can be increased from 8 torr to 65 torr ( 6), the pressure in the second filling tank 418a can be further increased.

Note that the temperature in the second filling tank 418a is lower than the thermal decomposition temperature of the TiCl ₄ gas filled in the second filling tank 418a. As will be described later, since the N ₂ gas filled in the first filling tank 414a is mixed with the TiCl ₄ gas filled in the second filling tank 418a, the temperature in the first filling tank 414a is also The temperature is preferably lower than the thermal decomposition temperature of TiCl ₄ gas. Thereby, thermal decomposition of TiCl ₄ gas can be suppressed.

(TiN film forming step (S30))
Subsequently, a step of supplying TiCl ₄ gas as a raw material gas into the processing chamber 201 (S 31), a step of purging the processing chamber 201 (S 32), and supplying NH ₃ gas as a reactive gas into the processing chamber 201. The process (S33) and the process of purging the inside of the processing chamber 201 (S34) are defined as one cycle, and this cycle is performed a predetermined number of times (S35), thereby forming a TiN film on the wafer 200. Below, each process S31-S34 is demonstrated in order.

(Step of supplying TiCl ₄ gas (S31))
In the step of supplying TiCl ₄ gas (S31), the first step of filling TiCl ₄ gas into the second filling tank 418a while filling the first filling tank 414a with N ₂ gas (S3).
1a), a second step (S31b) for preparing pressure feeding of TiCl ₄ gas into the processing chamber 201, a third step (S31c) for pressure feeding TiCl ₄ gas into the processing chamber 201, and a second filling. A fourth step (S31d) for exhausting the inside of the tank 418a is sequentially performed.

[First Step (S31a)]
In the first step (S31a), the open / close state of each valve of the source gas supply system is set as shown in FIG. That is, the first valve 413a provided in the first gas supply pipe 410a is opened and the second valve 415a is closed, and the flow rate is adjusted by the mass flow controller 412a in the first filling tank 414a as the first gas reservoir. Fill with ₂ gases. At the same time, the third valve 416a and the fifth valve 415c are opened and the fourth valve 418a is closed, and the TiCl ₄ gas generated by the vaporizer 414c is filled into the second filling tank 417a as the second gas reservoir.

Note that the pressure in the first filling tank 414a and the second filling tank 417a needs to be a temperature at which the gas to be filled does not liquefy, that is, a pressure equal to or lower than the vapor pressure of the gas to be filled. FIG. 6 shows a vapor pressure curve of TiCl ₄ gas as the source gas. The horizontal axis of FIG. 6 shows the temperature (K) of TiCl ₄ gas, and the vertical axis represents the vapor pressure of the TiCl ₄ gas (torr). According to FIG. 6, the vapor pressure of TiCl ₄ gas heated to 333.15 K (60 ° C.) is 65 torr. Therefore, when the temperature in the second filling tank 417a is 60 ° C., the pressure in the second filling tank 414a needs to be 65 torr or less in order to prevent liquefaction of the TiCl ₄ gas. When the capacity of the second tank 418a is 300 cc, the temperature is 60 ° C., and the pressure is 65 torr, the amount of TiCl ₄ filled in the second filling tank 414a, that is, in the processing chamber 201 every cycle of ALD. The amount of TiCl ₄ supplied is 25.6 cc.

  When the predetermined time elapses and the gas is filled in the first filling tank 414a and the second filling tank 418a, and the pressures in the first filling tank 414a and the second filling tank 418a reach predetermined pressures, respectively, Step 2 (S31b) is performed.

[Second Step (S31b)]
In the second step (S31b), the open / close state of each valve of the source gas supply system is set as shown in FIG. That is, the first valve 413a, the third valve 416a, and the fifth valve 415c are closed while the second valve 415a and the fourth valve 418a are closed. Thereafter, the third step (S31c) is performed. Note that the first valve 413a, the third valve 416a, and the fifth valve 415c are not necessarily closed at the same time, and are each closed when the pressure of the filling tank reaches a predetermined pressure.

[Third step (S31c)]
In the third step (S31c), the open / close state of each valve of the source gas supply system is set as shown in FIG. That is, with the first valve 413a and the fifth valve 415c closed, the second valve 415a, the third valve 416a, and the fourth valve 418a are opened. As a result, the TiCl ₄ gas filled in the second filling tank 417a is pumped by the N ₂ gas filled in the first filling tank 414a, and the first gas supply pipe 410a, the source gas nozzle 400a, and the source gas supply It is introduced into the processing chamber 201 through the hole 401a in a very short time (flash introduction). The mixed gas of TiCl ₄ gas and N ₂ gas introduced into the processing chamber 201 flows between the wafers 200 held in the boat 217 in parallel with the main surface of the wafers 200 and then processed through the exhaust pipe 231. It is discharged from the chamber 201. As the TiCl ₄ gas flows between the wafers 200, TiCl ₄ gas molecules are adsorbed on the surface of the wafer 200, and an adsorption layer of TiCl ₄ gas molecules is formed on the wafer 200.

Note that TiCl ₄ gas can be supplied alone into the processing chamber 201 by opening only the fourth valve 418a while the second valve 415a and the third valve 416a are closed. When the TiCl ₄ gas is supplied alone in this way, the moving speed of the TiCl ₄ gas is determined by the differential pressure between the second filling tank 417a and the processing chamber 201. However, in order to prevent the liquefaction of the TiCl ₄ gas, the pressure in the second filling tank 417a needs to be a pressure equal to or lower than the vapor pressure of the TiCl ₄ gas. Therefore, when supplying TiCl ₄ gas alone, the moving speed of the TiCl ₄ gas will limited by the vapor pressure of the TiCl ₄ gas.

In contrast, when the to pump TiCl ₄ gas with the pressurized N ₂ gas as in this embodiment, the moving speed of the TiCl ₄ gas, largely as compared with the case of moving the TiCl ₄ gas alone It becomes possible to raise. That is, according to this embodiment, even when the pressure in the second filling tank 417a is limited to a pressure equal to or lower than the vapor pressure of the TiCl ₄ gas, the pressure of the pressurized N ₂ gas is used. The moving speed of the TiCl ₄ gas can be greatly increased. Then, by increasing the moving speed of the TiCl ₄ gas, it is possible to increase the partial pressure of TiCl ₄ gas in the processing chamber 201 in a shorter time, the formation of the adsorption layer of the TiCl ₄ gas molecules to the wafer 200 on It can be performed in a shorter time.

In the third step (S31c), when the second valve 415a, the third valve 416a, and the fourth valve 418a are opened, the first valve 413a and the fifth valve 415c are kept closed. Thus, it is possible to prevent the pressurized N ₂ gas will flow back into the second gas supply pipe 410c.

In the third step (S31c), the second valve 415a, the third valve 416a, and the fourth valve 418a are simultaneously opened, or the fourth valve 418a, the third valve 416a, and the second valve 415a are opened in this order. To. If the second valve 415a and the third valve 416a are opened before the fourth valve 418a is opened, the pressurized N ₂ gas is introduced into the second filling tank 417a, so that the inside of the second filling tank 417a is pressure exceeds the vapor pressure of temporarily TiCl ₄ gas, and there is a fear that inviting liquefaction of TiCl ₄ gas.

When the predetermined time has elapsed and the pressure feeding of the TiCl ₄ gas into the processing chamber 201 is completed, the fourth step (S31d) is performed.

[Fourth Step (S31d)]
In the fourth step (S31d), the open / close state of each valve of the source gas supply system is set as shown in FIG. That is, the second valve 415a, the third valve 416a, and the fifth valve 415c are closed while the fourth valve 418a is opened, and residual gases in the second filling tank 417a, that is, TiCl ₄ gas and N ₂ gas are removed. By removing residual gas (especially inert gas) in the second filling tank 417a, the TiCl ₄ gas into the second filling tank 417a when the first step (S31a) is performed in the next ALD cycle is performed. The filling amount can be increased.

  After a predetermined time has passed, the residual gas in the second filling tank 417a is removed, and when the pressure in the second filling tank 417a is reduced to the pressure in the processing chamber 201, the fourth valve 418a is closed and the inside of the processing chamber 201 is purged. Step (S32) is performed. The fourth step (S31d) may be performed in parallel with a step (S32) of purging the inside of the processing chamber 201 described later.

(Step of purging the inside of the processing chamber 201 (S32))
In the process of purging the inside of the processing chamber 201 (S32), the opening degree of the APC valve 243 is adjusted while the supply of TiCl ₄ gas into the processing chamber 201 is stopped, and the TiCl remaining in the processing chamber 201 is retained. Remove ₄ gases. At this time, the tenth valve 413d is opened, and N ₂ gas as a purge gas is supplied into the processing chamber 201 through the inert gas supply pipe 410d, the third gas supply pipe 410b, and the reaction gas nozzle 400b. The exhaust efficiency of TiCl ₄ gas from the inside of the processing chamber 201 can be increased. When the removal of the TiCl ₄ gas from the inside of the processing chamber 201 is completed, a step of supplying NH ₃ gas (S33) is performed.

(Step of supplying NH ₃ gas (S33))
In the step of supplying NH ₃ gas (S33), the ninth valve 413b is opened, and NH ₃ gas as the reaction gas whose flow rate is adjusted by the mass flow controller 412b is supplied to the second gas supply pipe 410b, the reaction gas nozzle 400b, and the reaction gas. The gas is supplied into the processing chamber 201 through the supply hole 401b. At this time, the tenth valve 413d is opened, and N ₂ gas as a carrier gas is supplied into the processing chamber 201 through the inert gas supply pipe 410d, the third gas supply pipe 410b, and the reaction gas nozzle 400b. For example, diffusion of NH ₃ gas into the processing chamber 201 can be promoted, and the concentration of NH ₃ gas supplied into the processing chamber 201 can be adjusted.

The NH ₃ gas or the mixed gas of NH ₃ gas and N ₂ gas supplied into the processing chamber 201 flows between the wafers 200 held in the boat 217 in parallel with the main surface of the wafers 200, and then the exhaust pipe It is discharged from the processing chamber 201 through the H.231. As the NH ₃ gas flows between the wafers 200, the adsorption layer of TiCl ₄ gas molecules formed on the wafer 200 reacts with the NH ₃ gas, and the wafer 200 has less than one atomic layer to several atomic layers. A titanium nitride (TiN) film is formed.

When the reaction between the adsorption layer of TiCl ₄ gas molecules and the NH ₃ gas is completed after a predetermined time has elapsed, the ninth valve 413 b is closed, the supply of the NH ₃ gas into the processing chamber 201 is stopped, and the inside of the processing chamber 201 is stopped. Is performed (S34).

(Purging process chamber 201 (S34))
In the process of purging the inside of the processing chamber 201 (S34), the opening degree of the APC valve 243 is adjusted while the supply of NH ₃ gas into the processing chamber 201 is stopped, and the NH remaining in the processing chamber 201 is retained. ₃ Gas and reaction products are removed. At this time, the tenth valve 413d is opened, and N ₂ gas as a purge gas is supplied into the processing chamber 201 through the inert gas supply pipe 410d, the third gas supply pipe 410b, and the reaction gas nozzle 400b. Further, the exhaust efficiency of NH ₃ gas and reaction products from the inside of the processing chamber 201 can be increased.

(Repeating step (S35))
Then, a step of supplying TiCl ₄ gas into the processing chamber 201 (S31), a step of purging the processing chamber 201 (S32), a step of supplying NH ₃ gas as a reaction gas into the processing chamber 201 (S33), The process of purging the inside of the processing chamber 201 (S34) is one cycle, and this cycle is performed a predetermined number of times to form a TiN film having a desired film thickness on the wafer 200, and the TiN film formation process (S30) is completed. To do. Note that the thickness of the TiN film to be formed can be adjusted by adjusting the number of cycle repetitions. For example, when the thickness of the TiN nitride film generated per cycle is 1 mm, a 20 mm thick TiN film is formed by repeating this cycle 20 times.

(Temperature lowering and atmospheric pressure recovery step (S40))
Then, the supply of power to the heater 207 is stopped, the energization to the heater 207 is stopped, and the temperature in the processing chamber 201 and the wafer 200 is lowered to a predetermined temperature (for example, about room temperature). Further, the APC valve 243 is opened while the tenth valve 413d is opened and N ₂ gas as a purge gas is supplied into the processing chamber 201 through the inert gas supply pipe 410d, the third gas supply pipe 410b, and the reaction gas nozzle 400b. Is adjusted so that the pressure in the processing chamber 201 becomes a predetermined pressure (for example, atmospheric pressure).

(Wafer unloading step (S50))
Subsequently, the seal cap 219 is lowered by the boat elevator 115 to open the lower end of the manifold 209, and the boat 217 holding the processed wafers 200 is lowered and pulled out from the processing chamber 201 (boat unloading). At this time, it is preferable that the tenth valve 413 d is kept open and N ₂ gas is always allowed to flow into the processing chamber 201. Then, the processed wafer 200 is taken out from the unloaded boat 217 (wafer discharge), and the substrate processing step according to the present embodiment is completed.

As processing conditions in the TiN film forming step (S30) according to the present embodiment,
Temperature in the processing chamber 201: 250 ° C. to 550 ° C., preferably 350 ° C. to 450 ° C., more preferably 400 ° C.
Pressure in the processing chamber 201: 0.1 to 10 Torr
Is exemplified.

In addition, as a condition for supplying N ₂ gas into the first filling tank 414a in the step of supplying TiCl ₄ gas (S31),
Capacity of the first filling tank 414a: 100 to 1000 cc,
Temperature in the first filling tank 414a: 20-60 ° C, preferably 60 ° C
Pressure in the first filling tank 414a: 1 to 300 torr (independent of temperature),
Supply flow rate of inert gas (N ₂ gas): 1-10 slm
Is exemplified.

In addition, as a condition for supplying TiCl ₄ gas into the second filling tank 417a in the step of supplying TiCl ₄ gas (S31),
Capacity of the second filling tank 417a: 1/2000 to 5/2000 of the volume of the chamber,
Temperature in second filling tank 417a: 20-60 ° C, preferably 60 ° C
Pressure in second filling tank 417a: 65 torr (when tank temperature is 60 ° C.),
8 torr (when tank temperature is 20 ° C),
Supply flow rate of source gas (TiCl ₄ gas): 100 to 500 sccm,
Bubbling carrier gas (Ar gas) supply flow rate: 100 to 1000 sccm,
Is exemplified.

In addition, as gas supply conditions in the step of supplying NH ₃ gas (S33),
Supply flow rate of reaction gas (NH ₃ gas): 1000-10000 sccm,
Carrier gas (N ₂ gas) supply flow rate: 500 to 5000 sccm,
Reaction gas and carrier gas supply time: 2 to 20 seconds,
Is exemplified.

In addition, as a gas supply condition in the process of purging the inside of the processing chamber 201 (S32, S34),
Supply flow rate of purge gas (N ₂ gas): 1000 to 10000 sccm,
Purge gas supply time: 2 to 10 seconds is exemplified. A TiN film is formed on the wafer 200 by keeping each processing condition constant at a certain value within each range.

(4) Effects according to the present embodiment According to the present embodiment, the following one or more effects are achieved.

(A) According to this embodiment, the TiCl ₄ gas filled in the second filling tank 417a is pumped by the N ₂ gas filled in the first filling tank 414a, and the first gas supply pipe 410a, It is introduced into the processing chamber 201 through the source gas nozzle 400a and the source gas supply hole 401a in a very short time (flash introduction). In this manner, so as to pump the TiCl ₄ gas with pressurized N ₂ gas, the moving speed of the TiCl ₄ gas, it is possible to increase considerably in comparison with the case of moving the TiCl ₄ gas alone . That is, according to this embodiment, even when the pressure in the second filling tank 417a is limited to a pressure equal to or lower than the vapor pressure of the TiCl ₄ gas, the pressure of the pressurized N ₂ gas is used. The moving speed of the TiCl ₄ gas can be greatly increased. Then, by increasing the moving speed of the TiCl ₄ gas, it is possible to increase the partial pressure of TiCl ₄ gas in the processing chamber 201 in a shorter time, the formation of the adsorption layer of the TiCl ₄ gas molecules to the wafer 200 on It can be performed in a shorter time.

(B) According to this embodiment, the temperature in the first filling tank 414a and the second filling tank 418a is raised to a predetermined temperature before starting the TiN film forming step (S30). In this way, when the first step (S31a) to be described later is performed, the gas pressure in the first filling tank 414a and the second filling tank 418a is prevented from being liquefied and the gas pressure is sufficiently increased. Can be increased.

Note that the thermal decomposition of the TiCl ₄ gas can be suppressed by setting the temperature in the second filling tank 418a to a temperature lower than the thermal decomposition temperature of the TiCl ₄ gas filled in the second filling tank 418a. . In addition, by setting the temperature in the first filling tank 414a to be lower than the thermal decomposition temperature of the TiCl ₄ gas, the N ₂ gas filled in the first filling tank 414a is mixed with the TiCl ₄ gas. Thermal decomposition of TiCl ₄ gas can be suppressed.

(C) According to the present embodiment, the second step (S31b) is performed between the first step (S31a) and the third step (S31c). That is, after the first step (S31a) is completed, the open / close states of the valves of the source gas supply system are all closed as shown in FIG. 5C, and then the third step (S31c). To implement. As a result, the TiCl ₄ gas filled in the second filling tank 417a can be reliably pumped by the N ₂ gas filled in the first filling tank 414a. That is, when the valve opening / closing timing is deviated, N ₂ gas flows backward from the first filling tank 414a into the second gas supply pipe 410b, or inside the second filling tank 417a or the second gas supply pipe. It is possible to prevent the TiCl ₄ gas from flowing back into the first filling tank 414a from within 410b.

(D) In the third step (S31c) according to the present embodiment, the first valve 413a and the fifth valve 415c remain closed when the second valve 415a, the third valve 416a, and the fourth valve 418a are opened. State. Thus, it is possible to prevent the pressurized N ₂ gas will flow back into the second gas supply pipe 410c.

(E) In the third step (S31c) according to the present embodiment, the second valve 415a, the third valve 416a, and the fourth valve 418a are simultaneously opened, or the fourth valve 418a, the third valve 416a, and the second valve Open in the order of 415a. This can prevent the pressure in the second filling tank 417a may exceed the vapor pressure of temporarily TiCl ₄ gas, it is possible to prevent the liquefaction of the TiCl ₄ gas.

(F) In the fourth step (S31d) according to the present embodiment, residual gases in the second filling tank 417a, that is, TiCl ₄ gas and N ₂ gas are removed. By removing residual gas (especially inert gas) in the second filling tank 417a, the first step (S3
It is possible to further increase the filling amount of the TiCl ₄ gas into the second filling tank 417a when performing 1a).

<Other Embodiments of the Present Invention>
As mentioned above, although embodiment of this invention was described concretely, this invention is not limited to the above-mentioned embodiment, It can change variously in the range which does not deviate from the summary.

  For example, in the above-described embodiment, the case where the present invention is applied to a vertical substrate processing apparatus that processes a plurality of substrates simultaneously has been described. However, the present invention is not limited to the embodiment. For example, the present invention can be suitably applied to a single-wafer type substrate processing apparatus that processes substrates one by one. In the single-wafer type substrate processing measure, since the number of substrates to be processed is small and the size of the processing chamber is small, the time required for one cycle is short. Therefore, the amount of gas supplied in one cycle is vertical. The amount is smaller than that of the substrate processing apparatus. On the other hand, a vertical substrate processing apparatus with a large number of processed sheets has a large processing chamber capacity, so that the amount of gas supplied in one cycle is relatively large. Therefore, the present invention is more effective when applied to a vertical substrate processing apparatus.

For example, in the above-described embodiment, the case where the TiCl ₄ gas is supplied as the source gas has been described, but the present invention is not limited to such a form. For example, as source gases, TDMAT (Ti [N (CH ₃ ) ₄ ]), TDMAH (Hf [N (CH ₃ ) ₄ ]), TMA ((CH ₃ ) ₃ Al), TEMAH (Hf [N (C _{2 H 5) CH 3] 4)} , TEMAZ (Zr [(C 2 H 5) CH 3] 4), 3DMAS (SiH [N (CH 3)] 3), PET (Ta (OC 2 H 5) 5)) The present invention can also be suitably applied to the case of using a gas having a relatively low vapor pressure obtained by vaporizing any of the above.

  In particular, the present invention can be suitably applied to the case where a gas having a vapor pressure of 100 torr or less when heated, for example, is used as the source gas.

  For example, in the above-described embodiment, the case where the TiN film is formed on the wafer 200 has been described, but the present invention is not limited to such a form. For example, a metal oxide film or metal nitride film containing a metal element such as hafnium (Hf), zirconium (Zr), aluminum (Al), tantalum (Ta), platinum (Pt), nickel (Ni) is formed on the wafer 200. It can also be applied to.

  Further, a capacitor electrode having a structure in which an oxide such as a zirconium oxide film (ZrO film), a hafnium oxide film (HfO film), an aluminum oxide film (AlO film), and a metal compound to which an element is mainly added are laminated. The present invention can also be applied to a modification process relating to a transistor gate structure. For example, it can be applied to a zirconium aluminum oxide film (ZrAlO film), a hafnium aluminum oxide film (HfAlO film), a zirconium silicate film (ZrSiO film), a hafnium silicate film (HfSiO film), or a laminated film of the above films. .

  In the above-described embodiment, the example of the laminated film in which the insulating film is located on the conductive film has been described. However, the present invention is not limited to the laminated film in the form of sandwiching the insulating film with the conductive film or the insulating film. The present invention can also be applied to a laminated film on which a conductive film is positioned.

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

(Appendix 1)
According to one aspect of the invention,
A first gas reservoir provided in a gas supply pipe connected to the processing chamber is filled with an inert gas, and a second gas provided in the gas supply pipe downstream of the first gas reservoir is provided. Filling the raw material gas into the gas reservoir of
An on-off valve provided in the gas supply pipe between the first gas reservoir and the second gas reservoir, and the gas supply pipe between the second gas reservoir and the processing chamber Opening the on-off valves provided in the first gas reservoir, and pumping the source gas filled in the second gas reservoir with the inert gas filled in the first gas reservoir, and A method of manufacturing a semiconductor device having the above is provided.

(Appendix 2)
Preferably,
After the source gas is pumped into the processing chamber, the second on-off valve provided in the gas supply pipe between the first gas reservoir and the second gas reservoir is closed. A step of removing residual gas in the gas reservoir.

(Appendix 3)
According to another aspect of the invention,
A step of transporting the substrate into the processing chamber;
The first on-off valve provided in the gas supply pipe connected to the processing chamber is opened and the second on-off valve is closed to supply the gas between the first on-off valve and the second on-off valve. While filling the first gas reservoir provided in the pipe with the inert gas, the third on-off valve provided in the gas supply pipe on the downstream side of the second on-off valve is opened and the fourth A first step of closing an on-off valve and filling a source gas into a second gas reservoir provided in the gas supply pipe between the third on-off valve and the fourth on-off valve;
A second step of closing each of the first on-off valve and the third on-off valve in a state in which the second on-off valve and the fourth on-off valve are closed; and
The second on-off valve, the third on-off valve, and the fourth on-off valve are opened, and the source gas filled in the second gas reservoir is filled in the first gas reservoir. A third step of pumping into the processing chamber with an inert gas;
A fourth step of closing the third on-off valve with the fourth on-off valve open to remove residual gas in the second gas reservoir;
Transporting the substrate from the processing chamber,
A method of manufacturing a semiconductor device is provided in which a thin film is formed on the substrate by performing the first to fourth steps a predetermined number of times.

(Appendix 4)
According to yet another aspect of the invention,
A step of transporting the substrate into the processing chamber;
Forming a thin film on the substrate by alternately performing a step of supplying a source gas into the processing chamber and a step of supplying a reaction gas into the processing chamber a predetermined number of times;
Transporting the substrate from the processing chamber,
The step of supplying the source gas into the processing chamber includes:
The first on-off valve provided in the gas supply pipe connected to the processing chamber is opened and the second on-off valve is closed to supply the gas between the first on-off valve and the second on-off valve. While filling the first gas reservoir provided in the pipe with the inert gas, the third on-off valve provided in the gas supply pipe on the downstream side of the second on-off valve is opened and the fourth A first step of closing an on-off valve and filling a source gas into a second gas reservoir provided in the gas supply pipe between the third on-off valve and the fourth on-off valve;
A second step of closing each of the first on-off valve and the third on-off valve in a state in which the second on-off valve and the fourth on-off valve are closed; and
The second on-off valve, the third on-off valve, and the fourth on-off valve are opened, and the source gas filled in the second gas reservoir is filled in the first gas reservoir. A third step of pumping into the processing chamber with an inert gas;
A fourth step of closing the third on-off valve with the fourth on-off valve open to remove residual gas in the second gas reservoir, and a method for manufacturing a semiconductor device. .

(Appendix 5)
Preferably,
The source gas is a gas obtained by vaporizing any of TiCl ₄ , TDMAT, TMA, TEMAH, TEMAZ, 3DMAS, and PET.

(Appendix 6)
Also preferably,
The source gas is a gas having a vapor pressure of 100 torr or less when heated.

(Appendix 7)
Also preferably,
The inside of the first gas reservoir and the inside of the second gas reservoir are heated.

(Appendix 8)
According to another aspect of the invention,
A processing chamber for accommodating the substrate;
A raw material gas supply system for supplying an inert gas and a raw material gas into the processing chamber;
An exhaust system for exhausting the atmosphere in the processing chamber;
A control unit for controlling the gas supply system and the exhaust system,
The gas supply system has a first gas supply pipe connected to the processing chamber,
The first gas supply pipe includes an inert gas supply source, a first on-off valve, a first gas reservoir, a second on-off valve, a third on-off valve, and a second gas in order from the upstream side. A reservoir and a fourth on-off valve are provided;
A second gas supply pipe is connected to the first gas supply pipe between the second on-off valve and the third on-off valve,
The second gas supply pipe is provided with a substrate processing apparatus provided with a source gas supply source and a fifth on-off valve in order from the upstream side.

(Appendix 9)
Also preferably,
The controller is
The first on-off valve is opened and the second on-off valve is closed, and the first on-off valve is opened while the third on-off valve and the fifth on-off valve are opened while the first gas reservoir is filled with an inert gas. 4 after closing the on-off valve and filling the source gas into the second gas reservoir,
The second on-off valve, the third on-off valve, and the fourth on-off valve are opened, and the second gas reservoir is filled with the inert gas filled in the first gas reservoir. The raw material gas supply system and the exhaust system are controlled so that the raw material gas is pumped into the processing chamber.

(Appendix 10)
Also preferably,
The controller is
After the filling of the inert gas into the first gas reservoir and the filling of the source gas into the second gas reservoir are completed, the first gas reservoir is started before the feed of the source gas by the inert gas is started. The source gas supply system and the exhaust system are controlled so that the on-off valve, the second on-off valve, the third on-off valve, the fourth on-off valve, and the fifth on-off valve are closed for a predetermined time. To do.

(Appendix 11)
Also preferably,
The controller is
After the feed of the source gas by the inert gas is completed, the third on-off valve and the fifth on-off valve are closed with the fourth on-off valve opened, and the residual gas in the second gas reservoir The source gas supply system and the exhaust system are controlled so as to remove the gas.

(Appendix 12)
Also preferably,
The processing chamber is configured to be transported in a state where a plurality of substrates are stacked.

101 substrate processing apparatus 200 wafer (substrate)
201 processing chamber 202 processing furnace

Claims (5)

A first gas reservoir provided in a gas supply pipe connected to the processing chamber is filled with an inert gas, and a second gas provided in the gas supply pipe downstream of the first gas reservoir is provided. Filling the raw material gas into the gas reservoir of
An on-off valve provided in the gas supply pipe between the first gas reservoir and the second gas reservoir, and the gas supply pipe between the second gas reservoir and the processing chamber Opening the on-off valves provided in the first gas reservoir, and pumping the source gas filled in the second gas reservoir with the inert gas filled in the first gas reservoir, and A method for manufacturing a semiconductor device, comprising: A step of transporting the substrate into the processing chamber;
The first on-off valve provided in the gas supply pipe connected to the processing chamber is opened and the second on-off valve is closed to supply the gas between the first on-off valve and the second on-off valve. While filling the first gas reservoir provided in the pipe with the inert gas, the third on-off valve provided in the gas supply pipe on the downstream side of the second on-off valve is opened and the fourth A first step of closing an on-off valve and filling a source gas into a second gas reservoir provided in the gas supply pipe between the third on-off valve and the fourth on-off valve;
A second step of closing each of the first on-off valve and the third on-off valve in a state in which the second on-off valve and the fourth on-off valve are closed; and
The second on-off valve, the third on-off valve, and the fourth on-off valve are opened, and the source gas filled in the second gas reservoir is filled in the first gas reservoir. A third step of pumping into the processing chamber with an inert gas;
A fourth step of closing the third on-off valve with the fourth on-off valve open to remove residual gas in the second gas reservoir;
Transporting the substrate from the processing chamber,
A method of manufacturing a semiconductor device, wherein a thin film is formed on the substrate by performing the first to fourth steps a predetermined number of times. 3. The method of manufacturing a semiconductor device according to claim 1, wherein the source gas is a gas obtained by vaporizing any one of TiCl ₄ , TDMAT, TMA, TEMAH, and TEMAZ. A processing chamber for accommodating the substrate;
A raw material gas supply system for supplying an inert gas and a raw material gas into the processing chamber;
An exhaust system for exhausting the atmosphere in the processing chamber;
A control unit for controlling the source gas supply system and the exhaust system,
The source gas supply system has a first gas supply pipe connected to the processing chamber,
The first gas supply pipe includes an inert gas supply source, a first on-off valve, a first gas reservoir, a second on-off valve, a third on-off valve, and a second gas in order from the upstream side. A reservoir and a fourth on-off valve are provided;
A second gas supply pipe is connected to the first gas supply pipe between the second on-off valve and the third on-off valve,
The substrate processing apparatus, wherein the second gas supply pipe is provided with a source gas supply source and a fifth on-off valve in order from the upstream side. The controller is
The first on-off valve is opened and the second on-off valve is closed, and the first on-off valve is opened while the third on-off valve and the fifth on-off valve are opened while the first gas reservoir is filled with an inert gas. 4 after closing the on-off valve and filling the source gas into the second gas reservoir,
The second on-off valve, the third on-off valve, and the fourth on-off valve are opened, and the second gas reservoir is filled with the inert gas filled in the first gas reservoir. 5. The substrate processing apparatus according to claim 4, wherein the gas supply system and the exhaust system are controlled so that the raw material gas is pumped into the processing chamber.

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