JP2011187485A - Substrate processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate processing apparatus which minimizes the replacement volume of a process gas supply pipeline, and to improve the speed of switching process gases supplied to a reaction chamber. <P>SOLUTION: The substrate processing apparatus includes a processing chamber 52, housing a substrate; a plurality of processing gas supply means which supply a plurality of process gases into the processing chamber; a carrier gas supply means which supplies a carrier gas into the processing chamber; an exhaust means which exhausts the processing chamber of an atmosphere gas; and a control means which controls the plurality of process gas supply means, carrier gas supply means and exhaust means. The plurality of process gas supply means have upstream-side valves 56 and 63, flow control means 57, 58, and 64, downstream-side first valves 59 and 65, and downstream-side second valves 62 and 67 that are provided in increasing order on process gas pipelines from their upstream side. The carrier gas supply means are each connected between the downstream-side second valves 62 and 67 and the processing chamber 52, on the downstream side of valves 79 and 83 are provided on carrier gas pipelines. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a substrate processing apparatus for manufacturing a semiconductor device by performing thin film formation, oxidation treatment, impurity diffusion, annealing treatment, etching and the like on a substrate such as a silicon wafer.

  One of chemical vapor deposition methods is an atomic layer deposition method (ALD method). In ALD (Atomic Layer Deposition) method, two or more kinds of processing gases are alternately flowed on the substrate surface one by one under the film forming conditions such as temperature and time, and reacted with atoms on the substrate surface to form a single layer. This is a method for depositing a film, and since it is possible to control each monoatomic layer, it is possible to form a uniform film thickness, and it is possible to grow the film very densely as the film quality.

  The outline of a conventional gas supply system will be described with reference to FIG.

  A gas supply BOX 2 that supplies gas to the reaction tube 1 is connected to a first gas supply source, a second gas supply source, and a carrier gas supply source (not shown), and the first gas supply tube 4 and the second gas supply source. A supply pipe 6 is connected. The first gas supply pipe 4 ejects a processing gas supplied from a first gas supply source and a carrier gas which is an inert gas such as N2 supplied from a carrier gas supply source into the reaction pipe 1. The second gas supply pipe 6 is connected to the first nozzle 3 for discharging the processing gas from the second gas supply source and the carrier gas from the carrier gas supply source into the reaction pipe 1. 2 nozzles 5 are connected.

  The first gas supply pipe 4 is divided into two branches in the gas supply BOX 2, one of which is connected to the first switching valve 7 and the other is connected to the third switching valve 8. The second gas supply pipe 6 is also divided into two branches in the gas supply BOX 2, one of which is connected to the second switching valve 9 and the other is connected to the fourth switching valve 11.

  The first switching valve 7 and the third switching valve 8 connected to the first gas supply pipe 4 are respectively connected to a first MFC 12 and a third MFC 14 which are flow controllers on the upstream side. ing. The first MFC 12 is connected to the carrier gas supply valve 16 on the upstream side, and the third MFC 14 is connected to the first gas supply valve 17 on the upstream side.

  The second switching valve 9 and the fourth switching valve 11 connected to the second gas supply pipe 6 are respectively connected to the second MFC 13 and the fourth MFC 15 which are flow controllers on the upstream side. ing. The second MFC 13 joins between the first MFC 12 and the carrier gas supply valve 16 on the upstream side, and the fourth MFC 15 is connected to the second gas supply valve 18 on the upstream side. ing.

  When depositing a film on the substrate by the ALD method using the gas supply BOX 2, as shown in the processing sequence of FIG. 7, the first gas supply valve 17 and the third switching valve 8 are opened, The second switching valve 9 is closed and the processing gas is ejected from the first nozzle 3 into the reaction tube 1. When a predetermined time has elapsed, the third switching valve 8 is closed and the carrier gas supply is performed. The valve 16 and the first switching valve 7 are opened to introduce the carrier gas into the first gas supply pipe 4, and the residual gas in the first gas supply pipe 4 and the first nozzle 3 is replaced.

  In parallel with the residual gas replacement process, the second gas supply valve 18 and the fourth switching valve 11 are opened, the second switching valve 9 is closed, and the second switching valve 9 is closed in the reaction tube 1. When a predetermined time elapses, the fourth switching valve 11 is closed, the second switching valve 9 is opened, and the carrier gas is introduced into the second gas supply pipe 6. Then, the residual gas in the second gas supply pipe 6 and the second nozzle 5 is replaced.

  Further, during the replacement process of the second gas supply pipe 6 and the second nozzle 5, a processing gas is jetted into the reaction pipe 1 from the first nozzle 3. By repeating the above process, films are alternately deposited on the substrate.

  However, when a film is deposited on the substrate by the ALD method, each gas is mixed on the processing substrate, and in the reaction tube 1, the nozzles 3 and 5, It is necessary to flow the carrier gas into the gas supply pipes 4 and 6 to replace the processing gas with an inert gas. Since the gas supply pipes 4 and 6 are long, it takes a long time to switch the processing gas, and CVD. There was a problem that the film formation rate was slow compared to the method.

JP 2009-49367 A

  In view of such circumstances, the present invention provides a substrate processing apparatus that minimizes the replacement of the gas supply pipe and improves the film forming speed by improving the switching speed of the gas supplied into the reaction chamber.

  The present invention includes a processing chamber that accommodates a substrate, a plurality of processing gas supply units that respectively supply a plurality of processing gases into the processing chamber, a carrier gas supply unit that supplies a carrier gas into the processing chamber, and the processing chamber And a control means for controlling the plurality of processing gas supply means, the carrier gas supply means and the exhaust means, each of the plurality of processing gas supply means supplying a processing gas. A processing gas supply source to be processed and a processing gas pipe connected to the processing chamber, an upstream valve, a flow rate control means, a downstream first valve, and a downstream provided in the processing gas piping in order from the upstream side of the processing gas The carrier gas supply means has a carrier gas pipe connected to the carrier gas supply source and the processing chamber, and a key provided in the carrier gas pipe. A rear gas valve, and the carrier gas piping section is connected between the second downstream valve and the processing chamber on the downstream side of the carrier gas valve, and when the processing gas is removed, the downstream side The processing gas supply means for closing the first valve and the second downstream valve and supplying the processing gas pipe with the carrier gas valve open and exhausting the atmosphere in the processing chamber, The present invention relates to a substrate processing apparatus for controlling carrier gas supply means and exhaust means.

  According to the present invention, a processing chamber for containing a substrate, a plurality of processing gas supply means for supplying a plurality of processing gases into the processing chamber, a carrier gas supply means for supplying a carrier gas into the processing chamber, Exhaust means for exhausting the atmosphere in the processing chamber; and control means for controlling the plurality of processing gas supply means, the carrier gas supply means, and the exhaust means, each of the plurality of processing gas supply means being a processing gas A processing gas supply source for supplying gas, a processing gas pipe connected to the processing chamber, an upstream valve, a flow rate control means, and a downstream first valve provided in the processing gas pipe in order from the upstream side of the processing gas And a downstream second valve, and the carrier gas supply means is provided in a carrier gas pipe connected to the carrier gas supply source and the processing chamber, and provided in the carrier gas pipe. A carrier gas valve, and the carrier gas pipe is connected between the second downstream valve and the processing chamber on the downstream side of the carrier gas valve, and when the processing gas is removed, The processing gas supply means for closing the first side valve and the second downstream valve and supplying the carrier gas to the processing gas piping section with the carrier gas valve open, and exhausting the atmosphere in the processing chamber; Since the carrier gas supply means and the exhaust means are controlled, the gas supplied into the processing chamber can be switched by switching the upstream valve and the downstream valve, and exhaust is required when switching the gas. Since the length of the piping section can be shortened, the sequence time in the film forming process can be shortened and the film forming speed can be improved. Exhibit.

1 is a schematic perspective view of a substrate processing apparatus in the present invention. It is a schematic longitudinal cross-sectional view of the processing furnace in this invention. It is an AA arrow line view of FIG. It is a schematic explanatory drawing which shows the gas supply system in this invention. It is a schematic explanatory drawing of the gas supply system which shows the other Example of this invention. It is a schematic explanatory drawing which shows the conventional gas supply system. It is explanatory drawing which shows the conventional process sequence.

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

  First, the substrate processing apparatus 21 in the present invention will be described with reference to FIG.

  As an example, the substrate processing apparatus 21 is configured as a semiconductor manufacturing apparatus that performs a processing step in a manufacturing method of a semiconductor device (IC). In the following description, a case where a vertical apparatus that performs oxidation, diffusion processing, CVD processing, or the like is applied to the substrate as the substrate processing apparatus will be described.

  The substrate processing apparatus 21 in which a cassette 23 as a wafer carrier containing a wafer (substrate) 22 made of silicon or the like is used includes a housing 24. Below the front wall 25 of the housing 24, a front maintenance port (not shown) as an opening provided for maintenance is opened, and a front maintenance door (not shown) that opens and closes the front maintenance port. Z) is built. The front maintenance door is provided with a cassette loading / unloading port (substrate container loading / unloading port) (not shown) so as to communicate with the inside and outside of the casing 24. The cassette loading / unloading port is not shown. It is configured to be opened and closed by a device loading / unloading opening / closing mechanism. A cassette stage (substrate container delivery table) 26 is installed inside the casing 24 at the cassette loading / unloading exit. The cassette 23 is loaded onto the cassette stage 26 by an in-process transfer device (not shown) and unloaded from the cassette stage 26.

  The cassette stage 26 is placed so that the wafer 22 in the cassette 23 is in a vertical posture by the in-process transfer device, and the wafer inlet / outlet of the cassette 23 faces upward. The cassette stage 26 rotates the cassette 23 in the clockwise and vertical directions 90 degrees toward the rear of the housing 24, the wafer 22 in the cassette 23 is in a horizontal posture, and the wafer inlet / outlet of the cassette 23 Operation is possible so as to face the rear of the casing 24.

  A cassette shelf (substrate container mounting shelf) 27 is installed in a substantially central portion of the casing 24 in the front-rear direction, and the cassette shelf 27 stores a plurality of cassettes 23 in a plurality of rows and a plurality of rows. It is configured like this. The cassette shelf 27 is provided with a transfer shelf 29 in which the cassette 23 to be transferred by a wafer transfer mechanism 35 described later is stored. Further, a preliminary cassette shelf 31 is provided above the cassette stage 26 so as to preliminarily store the cassette 23.

  A cassette carrying device (substrate container carrying device) 32 is installed between the cassette stage 26 and the cassette shelf 27. The cassette transport device 32 is composed of a cassette elevator (substrate container lifting mechanism) 33 that can be lifted and lowered while holding the cassette 23, and a cassette transport mechanism (substrate container transport mechanism) 34 as a transport mechanism. The cassette 23 is transported between the cassette stage 26, the cassette shelf 27, and the spare cassette shelf 31 by continuous operation of the cassette elevator 33 and the cassette transport mechanism 34.

  Behind the cassette shelf 27, the wafer transfer mechanism (substrate transfer mechanism) 35 is installed, and the wafer transfer mechanism 35 can rotate or linearly move the wafer 22 in the horizontal direction. (Substrate transfer device) 36 and a wafer transfer device elevator (substrate transfer device lifting mechanism) 28 for moving the wafer transfer device 36 up and down. By continuous operation of the wafer transfer device 36 and the wafer transfer device elevator 28, a tweezer (substrate holder) 37 of the wafer transfer device 36 is used as a placement portion of the wafer 22 to a boat (substrate holder) 38. On the other hand, the wafer 22 is configured to be charged (charging) and loaded (discharged).

  A processing furnace 39 is provided at the upper rear portion of the casing 24. The lower end portion of the processing furnace 39 is configured to be opened and closed by a furnace port shutter (furnace port opening / closing mechanism) 41.

  Below the processing furnace 39, a boat elevator (substrate holder lifting mechanism) 42 is provided as a lifting mechanism for lifting the boat 38 to the processing furnace 39, and is connected to a lifting platform of the boat elevator 42. A seal cap 44 as a lid is horizontally installed on the arm 43 as a tool, and the seal cap 44 is configured to support the boat 38 vertically and to close the lower end of the processing furnace 39. Has been.

  The boat 38 has a plurality of holding members, and a plurality of (for example, about 50 to 150) wafers 22 are horizontally held in a state where the wafers 22 are aligned in the vertical direction with the center thereof aligned. It is configured.

  Above the cassette shelf 27, a clean unit 45 composed of a supply fan and a dustproof filter is provided so as to supply clean air, which is a cleaned atmosphere, and clean air is placed inside the casing 24. It is configured to be distributed.

  In addition, a clean unit 46 constituted by a supply fan and a dustproof filter for supplying clean air to the left end of the housing 24 opposite to the wafer transfer device elevator 28 and the boat elevator 42 side. The clean air blown out from the clean unit 46 flows through the wafer transfer device 36 and the boat 38, and is then sucked into an exhaust device (not shown) and exhausted outside the housing 24. It has become like that.

  Next, the operation of the substrate processing apparatus 21 will be described.

  The cassette 23 is loaded from a cassette loading / unloading port (not shown), and is placed on the cassette stage 26 so that the wafer 22 is in a vertical posture and the wafer loading / unloading port of the cassette 23 faces upward. Thereafter, the cassette 23 is moved to the rear of the casing 24 so that the wafer 22 in the cassette 23 is placed in a horizontal posture by the cassette stage 26 and the wafer inlet / outlet of the cassette 23 faces the rear of the casing 24. It is rotated 90 ° clockwise.

  Next, the cassette 23 is automatically transported and delivered by the cassette transport device 32 to the designated shelf position of the cassette shelf 27 or the spare cassette shelf 31 and temporarily stored. The cassette shelf 27 or the spare cassette shelf 31 is transported to the transfer shelf 29 by the cassette transport device 32 or directly transported to the transfer shelf 29.

  When the cassette 23 is transferred to the transfer shelf 29, the wafer 22 is picked up from the cassette 23 through the wafer inlet / outlet by the tweezer 37 of the wafer transfer device 36, and behind the transfer shelf 29. The boat 38 is loaded. The wafer transfer device 36 that has transferred the wafer 22 to the boat 38 returns to the cassette 23 and loads the next wafer 22 into the boat 38.

  When a predetermined number of wafers 22 are loaded into the boat 38, the lower end portion of the processing furnace 39 closed by the furnace port shutter 41 is opened by the furnace port shutter 41. Subsequently, the boat 38 holding the group of wafers 22 is loaded into the processing furnace 39 when the seal cap 44 is lifted by the boat elevator 42.

  After loading, arbitrary processing is performed on the wafer 22 in the processing furnace 39. After the processing, the wafer 22 and the cassette 23 are dispensed to the outside of the casing 24 in the reverse procedure to the above.

  Next, the processing furnace 39 applied to the substrate processing apparatus 21 will be described with reference to FIGS.

  A reaction tube 48 as a reaction vessel for processing the wafer 22 as a substrate is provided inside a heater 47 which is a heating device (heating means), and a manifold 49 such as stainless steel is provided at the lower end of the reaction tube 48. The lower end opening of the manifold 49 is hermetically closed via the O-ring 51 by the seal cap 44 that is a lid, and is provided at least with the reaction tube 48, the air-tight member, and the O-ring 51. A processing chamber 52 is formed by the manifold 49 and the seal cap 44.

  The boat 38 as a substrate holding member (substrate holding means) is erected on the seal cap 44 via a boat support base 53, and the boat support base 53 serves as a holding body for holding the boat 38. . Further, a plurality of wafers 22 to be batch-processed are stacked in a multi-stage in the tube axis direction in a horizontal posture on the boat 38, and when the boat 38 is loaded into the processing chamber 52, the wafers are heated by the heater 47. 22 is heated to a predetermined temperature.

  Two gas supplies, that is, a first gas supply pipe 54 and a second gas supply pipe 55, which are piping sections, are used as supply paths for supplying a plurality of types of processing gases to the processing chamber 52, in this embodiment, two types of processing gases. A tube is provided.

  The first gas supply pipe 54 includes a first raw material supply valve 56 which is an upstream valve for supplying / stopping raw materials in order from the upstream direction, and a liquid mass flow controller (MFC) which is a flow control device (flow control means). ) 57, a carburetor 58, and a first switching valve 59 that is a downstream first valve, and a first carrier gas supply pipe 61 that supplies a carrier gas downstream of the first switching valve 59 is joined. In addition, a first final valve 62 that is a downstream second valve is provided on the downstream side of the junction with the first carrier gas supply pipe 61. Further, a first process gas supply means includes a liquid source supply source (not shown), the first source supply valve 56, the liquid MFC 57, the vaporizer 58, the first switching valve 59, and the first final valve 62. Is configured.

  In the second gas supply pipe 55, a second raw material supply valve 63 that is an upstream valve that sequentially supplies / stops the raw material from the upstream direction, a first MFC 64 that is a flow rate control device (flow rate control means), A second switching valve 65, which is a downstream first valve, is provided, and a second carrier gas supply pipe 66 that supplies a carrier gas downstream from the second switching valve 65 is joined, and the second switching valve 65 is joined. A second final valve 67, which is a downstream second valve, is provided on the downstream side of the junction with the carrier gas supply pipe 66. Further, a processing gas supply source (not shown), the second gas supply pipe 55, the second raw material supply valve 63, the first MFC 64, the second switching valve 65, and the second final valve 67 are included. A second processing gas supply means is configured.

  A carrier gas supply pipe 68 for supplying a carrier gas from a carrier gas supply source (not shown) is provided upstream of the first carrier gas supply pipe 61 and the second carrier gas supply pipe 66, and the carrier The gas supply pipe 68 is provided with a carrier gas supply valve 69 which is an upstream side valve for supplying / stopping carrier gas from a carrier gas supply source, and is divided into four forks on the downstream side. Branching into a supply pipe 61, the second carrier gas supply pipe 66, a third carrier gas supply pipe 71, and a fourth carrier gas supply pipe 72. Further, a carrier gas supply source (not shown), the carrier gas supply pipe 68, the first carrier gas supply pipe 61, the second carrier gas supply pipe 66, the third carrier gas supply pipe 71, the fourth carrier gas supply pipe 68, the first carrier gas supply pipe 61, the second carrier gas supply pipe 66, The carrier gas supply pipe 72, the second to fifth MFCs 73, 75, 77, 81, the third to sixth switching valves 74, 76, 78, 82, the third and fourth final valves 79, 83 are used as carriers. It constitutes a gas supply means.

  The first carrier gas supply pipe 61 is provided with a second MFC 73 and a third switching valve 74 which are flow rate control devices (flow rate control means) in order from the upstream direction, and the second carrier gas supply pipe 66 is provided. Are provided with a third MFC 75 and a fourth switching valve 76 which are flow rate control devices (flow rate control means) in order from the upstream side. The third carrier gas supply pipe 71 has a fourth MFC 77 as a flow rate control device (flow rate control means), a fifth switching valve 78 and a third final valve 79 as a carrier gas valve in order from the upstream direction. , And merges with the first gas supply pipe 54 on the downstream side of the third final valve 79. The fourth carrier gas supply pipe 72 has a fifth MFC 81 as a flow rate control device (flow rate control means), a sixth switching valve 82 and a fourth final valve 83 as a carrier gas valve in order from the upstream direction. And is joined to the second gas supply pipe 55 on the downstream side of the fourth final valve 83.

  The first raw material supply valve 56, the liquid MFC 57, the vaporizer 58, the first switching valve 59, the second raw material supply valve 63, the first MFC 64, and the second switching valve 65. The carrier gas supply valve 69, the second MFC 73, the third switching valve 74, the third MFC 75, the fourth switching valve 76, the fourth MFC 77, the fifth switching valve 78, The fifth MFC 81, the sixth switching valve 82, and the piping connected thereto constitute a gas supply BOX 80.

  A first nozzle 84 is provided at the distal end of the first gas supply pipe 54 on the downstream side. The first nozzle 84 is formed in a circular arc space between the inner wall of the reaction tube 48 constituting the processing chamber 52 and the wafer 22, and on the inner wall above the lower portion of the reaction tube 48. 22 along the stacking direction. A plurality of first gas supply holes 85, which are gas supply holes, are formed in the side surface of the first nozzle 84. The first gas supply holes 85 extend from the lower part to the upper part, respectively. They have the same opening area and are provided at the same opening pitch.

  A second nozzle 86 is provided at the distal end of the second gas supply pipe 55 on the downstream side. The second nozzle 86 is arranged in a circular arc space between the inner wall of the reaction tube 48 constituting the processing chamber 52 and the wafer 22, and on the inner wall above the lower portion of the reaction tube 48. 22 along the stacking direction. In addition, a plurality of second gas supply holes 87, which are gas supply holes, are formed in the side surface of the second nozzle 86, and each of the second gas supply holes 87 extends from the bottom to the top. They have the same opening area and are provided at the same opening pitch.

  For example, when the raw material supplied from the first gas supply pipe 54 is liquid, the first gas supply pipe 54 is connected to the first raw material supply valve 56, the liquid MFC 57, the vaporizer 58, and A processing gas is merged with the first carrier gas supply pipe 61 via the first switching valve 59 and further into the processing chamber 52 via the first final valve 62 and the first nozzle 84. Supplied. When the raw material supplied from the first gas supply pipe 54 is a gas, the liquid MFC 57 is replaced with a gas MFC, and the vaporizer 58 becomes unnecessary. Further, the second gas supply pipe 55 merges with the second carrier gas supply pipe 66 via the second raw material supply valve 63, the first MFC 64, and the second switching valve 65, Further, a processing gas is supplied into the processing chamber 52 through the second final valve 67 and the second nozzle 86.

  The processing chamber 52 is connected to a gas exhaust pipe 88 which is an exhaust pipe for exhausting gas, and the gas exhaust pipe 88 is connected to a vacuum pump 91 which is an exhaust device (exhaust means) through an exhaust valve 89. The gas in the processing chamber 52 is evacuated by the vacuum pump 91. The exhaust valve 89 is an open / close valve capable of opening / closing the valve to stop the evacuation / evacuation of the processing chamber 52 and further adjusting the valve opening to adjust the pressure of the processing chamber 52. .

  In the central portion of the reaction tube 48, the boat 38 for mounting a plurality of wafers 22 in multiple stages at the same interval is provided. The boat 38 is operated by the boat elevator 42 (see FIG. 1). The tube 48 can be entered and exited. Further, a boat rotation mechanism 92 for rotating the boat 38 is provided below the seal cap 44 so as to improve the uniformity of processing, and by driving the boat rotation mechanism 92, the boat support base The boat 38 supported by 53 rotates.

  The controller 93 which is a control unit (control means) includes the first and second raw material supply valves 56 and 63, the carrier gas supply valve 69, the liquid MFC 57, and the first to fifth MFCs 64, 73, 75, 77, 81, the first to sixth switching valves 59, 65, 74, 76, 78, 82 and the exhaust valve 89, the heater 47, the vacuum pump 91, the boat rotating mechanism 92, the boat elevator 42, It is connected to the.

  Further, the controller 93 opens and closes the first and second raw material supply valves 56 and 63 and the carrier gas supply valve 69, the liquid MFC 57 and the first to fifth MFCs 64, 73, 75, 77 and 81. The first to sixth switching valves 59, 65, 74, 76, 78, 82, opening / closing and pressure adjustment of the exhaust valve 89, temperature adjustment of the heater 47, the vacuum pump 91 Starting / stopping, adjusting the rotation speed of the boat rotating mechanism 92, and controlling the lifting / lowering operation of the boat elevator 42.

  Next, an example of a film forming process using the ALD method will be described with reference to FIG. 4 based on an example of forming an HfO 2 film using TEMAH and O 3 which is one of the semiconductor device manufacturing steps.

  In the ALD method, for example, in the case of forming an HfO2 film, a high quality film can be formed at a low temperature of 180 to 250 ° C. using TEMAH (Hf [NCH3 C2 H5] 4, tetrakismethylethylaminohafnium) and O3 (ozone). is there.

  First, the wafer 22 is loaded into the boat 38 and loaded into the processing chamber 52. After the boat 38 is loaded, the following four steps are sequentially executed.

(Step 1)
TEMAH is passed through the first gas supply pipe 54 and carrier gas (N2) is passed through the carrier gas supply pipe 68. Next, the first raw material supply valve 56, the first switching valve 59 and the first final valve 62 of the first gas supply pipe 54 are opened, and the carrier gas supply of the carrier gas supply pipe 68 is further opened. The valve 69, the third switching valve 74 of the first carrier gas supply pipe 61, and the exhaust valve 89 (see FIG. 2) of the gas exhaust pipe 88 are opened.

  The carrier gas flows from the first carrier gas supply pipe 61 and the flow rate is adjusted by the second MFC 73. Further, TEMAH flows from the first gas supply pipe 54, the flow rate is adjusted by the liquid MFC 57, the vaporized by the vaporizer 58, the carrier gas whose flow rate is adjusted is mixed, and the first final valve 62 is mixed. Then, the gas is exhausted from the gas exhaust pipe 88 while being supplied into the processing chamber 52 from the first gas supply hole 85 (see FIG. 3) of the first nozzle 84.

  At this time, the pressure in the processing chamber 52 is adjusted by appropriately adjusting the exhaust valve 89, and the pressure in the processing chamber 52 is maintained at 30 to 500 Pa, for example, 100 Pa. The supply amount of TEMAH controlled by the liquid MFC 57 is 0.01 to 0.1 g / min, and the time for exposing the wafer 22 to the TEMAH gas is 30 to 180 seconds. Further, at this time, the temperature of the heater 47 is set so that the temperature of the wafer 22 is in a range of 180 to 250 ° C., for example, 250 ° C., and TEMAH is supplied into the processing chamber 52, Surface reaction (chemical adsorption) with a surface portion such as a base film on the wafer 22 occurs.

(Step 2)
When replacing the first nozzle 84 and the processing chamber 52, the first switching valve 59 and the first final valve 62 are closed, and the supply of TEMAH into the processing chamber 52 is stopped. To do. At this time, the exhaust valve 89 of the gas exhaust pipe 88 is kept open, and the vacuum pump 91 (see FIG. 2) exhausts the processing chamber 52 to 20 Pa or less, and residual TEMAH gas is processed into the processing. Exclude from the chamber 52.

  At this time, by opening the fifth switching valve 78 and the third final valve 79 of the third carrier gas supply pipe 71, the carrier gas whose flow rate is adjusted by the fourth MFC 77 is changed to the first carrier gas supply pipe 71. The first nozzle 84 is supplied to the processing chamber 52 from the first gas supply hole 85 of the first nozzle 84 through the fifth switching valve 78 and the third final valve 79. The inside of the chamber 52 is replaced with the carrier gas (N2), and the effect of eliminating the residual TEMAH gas is enhanced.

(Step 3)
After the residual TEMAH gas is removed, the fifth switching valve 78 and the third final valve 79 are closed, and O 3 flows through the second gas supply pipe 55. Next, the second raw material supply valve 63, the second switching valve 65, and the second final valve 67 of the second gas supply pipe 55 are opened, and the second carrier gas supply pipe 66 is further opened. The fourth switching valve 76 is opened.

  The carrier gas flows from the second carrier gas supply pipe 66 and the flow rate is adjusted by the third MFC 75. Further, O3 flows from the second gas supply pipe 55, the flow rate of which is adjusted by the first MFC 64, the carrier gas whose flow rate is adjusted is mixed, and the second nozzle 67 is passed through the second final valve 67. The gas is exhausted from the gas exhaust pipe 88 while being supplied into the processing chamber 52 from the second gas supply hole 87 (see FIG. 3).

  At this time, the exhaust valve 89 is appropriately adjusted to maintain the pressure in the processing chamber 52 within a range of 30 to 500 Pa, for example, 130 Pa. Further, the time for exposing the wafer 22 to O3 is 10 to 120 seconds. At this time, the temperature of the wafer 22 is in the range of 180 to 250 ° C., for example, 250 ° C. The heater 47 is set so that By supplying O 3, TEMAH and O 3 chemically adsorbed on the surface of the wafer 22 react with each other to form an HfO 2 film on the wafer 22.

(Step 4)
When the second nozzle 86 and the processing chamber 52 are replaced after the HfO2 film is formed, the second switching valve 65 and the second final valve 67 are closed, and the inside of the processing chamber 52 is closed. The supply of O3 to is stopped. At this time, the exhaust valve 89 of the gas exhaust pipe 88 is kept open, the inside of the processing chamber 52 is evacuated by the vacuum pump 91, and the gas after contributing to the film formation of the remaining O3 is removed. .

  At this time, by opening the sixth switching valve 82 and the fourth final valve 83 of the fourth carrier gas supply pipe 72, the carrier gas whose flow rate is adjusted by the fifth MFC 81 is changed to the first carrier gas supply pipe 72. 6 is supplied into the processing chamber 52 from the second gas supply hole 87 of the second nozzle 86 through the switching valve 82 and the fourth final valve 83, and the second nozzle 86, the processing The inside of the chamber 52 is replaced with the carrier gas (N2), and the effect of removing the gas after contributing to the film formation of the remaining O3 is enhanced.

  In the first cycle, the above-described steps 1 to 4 are performed, and in the second and subsequent steps, a step of closing the sixth switching valve 82 and the fourth final valve 83 before step 1 is added. The processing from 'to step 4 is performed. The above step 1 (step 1 ') to step 4 are defined as one cycle, and a HfO2 film having a predetermined thickness can be formed on the wafer 22 by repeating the cycle a plurality of times.

  In the above description, the processing from step 1 to step 4 is sequentially performed. However, in order to shorten the sequence time, step 2 and step 3 or step 3 and step 4 may be overlapped. 4 partial processes may overlap. For example, as shown in FIG. 4, the fifth switching valve 78, the third final valve 79, the sixth switching valve 82, and the fourth final valve 83 are simultaneously open, that is, the One gas supply pipe 54, the first nozzle 84, the second gas supply pipe 55, and the second nozzle 86 may be simultaneously replaced with a carrier gas.

  As described above, in the present invention, the carrier gas supply pipe 68 is branched into four forks, and the first carrier gas supply pipe 61 that joins the first gas supply pipe 54 is located downstream of the joining point. The first final valve 62 is provided, the second carrier gas supply pipe 66 that joins the second gas supply pipe 55 is provided with the second final valve 67 on the downstream side of the joining point, The third final valve 79 is provided in the third carrier gas supply pipe 71 that joins the first gas supply pipe 54 and the downstream side of the first final valve 62, and the second gas supply pipe 55 Since the fourth final valve 83 is provided in the fourth carrier gas supply pipe 72 that merges on the downstream side of the second final valve 67, the gas supplied into the processing chamber 52 is switched, or Gas supply pipe and the nozzle can be carried out by a gas replacement process chamber switching of the first to fourth final valve 62,67,79,83. Accordingly, the portion to be replaced or purged is downstream of the first to fourth final valves 62, 67, 79, and 83. Therefore, the length of the gas supply pipe that needs to be replaced when switching the gas is increased. It can be shortened, the sequence time in the film forming process can be shortened, and the film forming speed can be improved.

  As another embodiment, as shown in FIG. 5, for example, the first gas supply pipe 54 is branched upstream of the first final valve 62, and the branched raw material exhaust pipe 94 is replaced with a gas exhaust pipe 88. And a fifth final valve 95 is provided in the middle of the raw material exhaust pipe 94.

  By providing the raw material exhaust pipe 94 and the fifth final valve 95, for example, a liquid raw material is used in the film forming process, and the liquid is reliquefied in the first gas supply pipe 54 or liquid is supplied at the time of resupply. When the control of the MFC 57 is difficult to stabilize, the raw material can be exhausted directly from the first gas supply pipe 54 without going through the first nozzle 84 or the processing chamber 52, and the replacement in the first gas supply pipe 54 can be further performed. Processing can be performed easily.

  In the present invention, the case where the HfO2 film is formed on the wafer 22 has been described. However, it goes without saying that the present invention is applicable not only to the HfO2 film but also to other film types. Absent.

21 substrate processing apparatus 22 wafer 39 processing furnace 48 reaction tube 52 processing chamber 54 first gas supply tube 55 second gas supply tube 56 first raw material supply valve 57 liquid MFC
59 First switching valve 62 First final valve 63 Second raw material supply valve 64 First MFC
65 Second switching valve 67 Second final valve 68 Carrier gas supply pipe 69 Carrier gas supply valve 73 Second MFC
74 Third switching valve 75 Third MFC
76 4th switching valve 77 4th MFC
78 Fifth switching valve 79 Third final valve 81 Fifth MFC
82 Sixth switching valve 83 Fourth final valve 91 Vacuum pump 93 Controller 94 Raw material exhaust pipe 95 Fifth final valve

Claims (1)

  A processing chamber for storing a substrate; a plurality of processing gas supply means for supplying a plurality of processing gases into the processing chamber; a carrier gas supplying means for supplying a carrier gas into the processing chamber; and an atmosphere in the processing chamber is evacuated. And a control means for controlling the plurality of processing gas supply means, the carrier gas supply means, and the exhaust means, wherein the plurality of processing gas supply means each supply a processing gas. A processing gas pipe connected to the source and the processing chamber, an upstream valve, a flow rate control means, a downstream first valve, and a downstream second valve provided in this processing gas piping from the upstream side of the processing gas. The carrier gas supply means includes a carrier gas supply source and a carrier gas pipe connected to the processing chamber, and a carrier gas provided in the carrier gas pipe And the carrier gas piping section is connected between the downstream second valve and the processing chamber on the downstream side of the carrier gas valve, respectively. The processing gas supply means, the carrier, and the carrier gas are supplied to the processing gas pipe section with the one valve and the second downstream valve closed and the carrier gas valve opened, and the atmosphere in the processing chamber is exhausted. A substrate processing apparatus for controlling a gas supply means and the exhaust means.

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