JP2004055880A - Substrate processing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate processing device that can shorten a temperature rise/fall time of a processing chamber. <P>SOLUTION: A CVD device 2 is equipped with a process tube 12 wherein the processing chamber 11 is formed to house a boat 22 holding a plurality of wafers 1, a heater 32 that is arranged around the process tube 12 and heats the processing chamber 11, and a heat insulating tank 34 arranged outside the heater 32. In such a structure, a reflection member 31 for reflecting a heat of the heater 32 to the process tube 12 is formed on the inner circumference of a bell jar 30 arranged between the heater 32 and the heat insulation tank 34, and a cooling air passage 36 is formed for distributing a cooling air 35 between the bell jar 30 and the tank 34. Thus, the heat of the heater is thoroughly supplied to the processing chamber through the reflection member, so that the temperature rise/fall time can be shortened, performance or throughput of the device can be improved, and the shallow joint of ICs can be realized. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a substrate processing apparatus for performing a thermal treatment on a substrate, for example, for performing a thermal treatment on a semiconductor wafer (hereinafter, referred to as a wafer) in which a semiconductor integrated circuit device (hereinafter, referred to as an IC) is formed. Regarding what is effective to use.
[0002]
[Prior art]
In a method of manufacturing an IC, for example, a batch-type vertical hot-wall type CVD apparatus (hereinafter, referred to as a "batch-type vertical wall type CVD apparatus") is used as one of substrate processing apparatuses for forming a thin film such as a CVD film, diffusing impurities, etching, etc. A CVD apparatus is used. The CVD apparatus includes a process tube that forms a processing chamber into which a wafer is loaded, a resistance heating member (hereinafter, referred to as a heater) that heats the inside of the process tube, and a heat insulating tank installed outside the heater. A plurality of wafers are loaded into the processing chamber from a furnace port at the lower end in a state of being stacked by a boat, and the processing chamber is heated by a heater, so that a CVD film is formed on the wafer by a thermal CVD reaction. Have been.
[0003]
[Problems to be solved by the invention]
However, in such a CVD apparatus, the following problems have been pointed out in recent years. Since the time for heating and cooling the wafer is prolonged, it has become difficult to manufacture a recent shallow junction IC. Since thermal energy from the heater cannot be efficiently supplied to the wafer, energy is wasted.
[0004]
Therefore, for example, with reference to JP-A-5-13674 and JP-A-2001-208478, a heater is provided by installing a reflecting member outside the heater and directing the heat energy of the heater all toward the wafer. A technique for efficiently supplying the thermal energy to the wafer can be proposed.
[0005]
However, in a CVD apparatus in which a reflecting member is provided outside the heater, the thermal energy from the heater can be efficiently supplied to the wafer, but the cooling time inside the heat insulating tank cannot be reduced.
[0006]
An object of the present invention is to provide a substrate processing apparatus capable of shortening a temperature rise / fall time.
[0007]
[Means for Solving the Problems]
A substrate processing apparatus according to the present invention includes a process tube having a processing chamber for accommodating a substrate, a resistance heating member installed to surround the process tube and heating the substrate, and a resistance heating member installed outside the resistance heating member. In a substrate processing apparatus comprising:
A reflecting member for reflecting the heat of the resistance heating member toward the process tube is provided between the resistance heating member and the heat insulation tank, and a cooling medium is provided between the reflection member and the heat insulation tank. It is characterized in that a cooling medium flow passage for circulation is formed.
[0008]
According to the above-described means, the heat of the resistance heating member can be efficiently supplied to the substrate by directing the heat of the resistance heating member to the process tube side by the reflection member, thereby shortening the time required for temperature rise. be able to. Further, by circulating the cooling medium through the cooling medium flow passage, the cooling time inside the heat insulating tank can be reduced.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0010]
In the present embodiment, as shown in FIG. 3, the substrate processing apparatus according to the present invention is a CVD apparatus (batch type vertical hot wall type CVD apparatus) 2 for forming a CVD film on a wafer in an IC manufacturing method. It is configured. Here, the outline of the CVD apparatus will be described.
[0011]
A cassette transfer unit 50 is provided on a front surface of the casing 10 of the CVD apparatus 2. A cassette shelf 51 is provided inside the housing 10 so as to face the cassette transfer unit 50, and a spare cassette shelf 52 is provided above the cassette transfer unit 50. A cassette transfer device 53 is provided between the cassette transfer unit 50 and the cassette shelf 51, and a wafer transfer device 54 is provided behind the cassette shelf 51. A boat elevator 55 is provided behind the wafer transfer machine 54, and a vertical reactor 56 is provided above the boat elevator 55.
[0012]
The cassette transfer unit 50 includes two sets of a cassette stage 58 on which two cassettes 57, which are wafer transfer containers (wafer carriers), can be placed, and a wafer attitude aligner 59 below the cassette stage 58. When the cassette 57 conveyed from the apparatus (not shown) is placed on the cassette stage 58 in a vertical posture (that is, when the wafer 1 stored in the cassette 57 is placed in a vertical posture, the wafer posture aligner 59 is moved to the cassette 57. The positions of the wafers (not shown) are aligned so that the notches and orientation flats of the wafers are located at the same position.
[0013]
The cassette stage 58 is rotated 90 degrees, and the cassette 57 is placed in a horizontal posture, and the cassette 57 can be transported by the cassette transporter 53.
[0014]
The cassette transfer device 53 includes a robot arm 60 that can move back and forth in the front-rear direction. The robot arm 60 is capable of traversing and moving up and down. The cassette 57 is transported to the shelf 51 or the spare cassette shelf 52.
[0015]
The arm 61 extending from the boat elevator 55 is provided with a seal cap 21, and the boat 22 as a wafer holder is placed on the seal cap 21. The boat 22 holds wafers in multiple stages in a horizontal posture, and is carried into and out of a vertical reaction furnace 56 by a boat elevator 55.
[0016]
The wafer transfer device 54 is provided rotatably and vertically movable, and includes a wafer holding portion 62 that can move forward and backward. The wafer holding portion 62 has a plurality of wafer holding plates 63, and a plurality of wafers are collectively or one by one. It can be held.
[0017]
The wafer transfer machine 54 transfers a plurality of wafers at once or one wafer at a time from the cassette 57 of the cassette shelf 51 to the boat 22 in a lowered state.
[0018]
When a predetermined number of wafers are transferred to the boat 22, the boat 22 is loaded into the vertical reaction furnace 56, and the wafers are processed.
[0019]
The processed wafer is transferred to the cassette 57 of the cassette shelf 51 by an operation reverse to the above-described operation, further transferred to the cassette transfer unit 50 by the cassette transfer device 53, and unloaded by an external transfer device (not shown).
[0020]
Next, the vertical reactor 56 will be described in detail with reference to FIG. The vertical reaction furnace 56 includes a process tube 12 in which a vertical processing chamber 11 is formed. The process tube 12 is made of quartz glass, is formed in a cylindrical shape with its upper end closed, and is vertically disposed so that its center line is vertical, and is fixedly supported. The lower end opening of the process tube 12 constitutes a furnace port 13 for taking in and out the wafer. As shown in FIG. 2, the outer peripheral surface of the process tube 12 is coated with a silicon carbide (SiC) film 14.
[0021]
A manifold 16 formed in a short cylindrical shape is coaxially disposed below the process tube 12, and the manifold 16 is supported by the casing 10 of the CVD apparatus 2. The process tube 12 is mounted on the manifold 16 with the seal ring 15 interposed therebetween and is supported by the housing 10 in a hermetically sealed state. A seal ring 15 is interposed. One end of an exhaust pipe 17 whose other end is connected to an exhaust device (not shown) is connected to a side wall of the manifold 16, and the exhaust pipe 17 exhausts the processing chamber 11. A gas introduction pipe 18 whose other end is connected to a source gas supply device, a carrier gas supply device, and a purge gas supply device (none of which is shown) is inserted through another portion of the side wall of the manifold 16. The outlet end of the gas introduction pipe 18 is arranged on the upper end side of the processing chamber 11. The gas introduced into the upper end of the processing chamber 11 by the gas introduction pipe 18 flows down the processing chamber 11 and is exhausted by the exhaust pipe 17. The lower end opening of the manifold 16 constitutes a boat loading / unloading port 19, and the seal cap 21 which is raised and lowered by the boat elevator 55 is abutted on the boat loading / unloading port 19 from below in the vertical direction with the seal ring 20 interposed therebetween. It has become so. The seal cap 21 is constructed in a disk shape having an outer diameter larger than the inner diameter of the boat loading / unloading port 19, and is moved up and down by a boat elevator 55 in a boat loading / unloading chamber formed by the casing 10 below the process tube 12. It has become so.
[0022]
A boat 22 is vertically supported on the seal cap 21. The boat 22 includes a pair of end plates 23 and 24 at the top and bottom, and three holding members 25 vertically disposed between the both end plates 23 and 24. Are provided with a plurality of holding grooves 26 arranged at equal intervals in the longitudinal direction and opened so as to face each other. The boat 22 is configured such that the wafers 1 are inserted between the holding grooves 26 of the three holding members 25 so that the plurality of wafers 1 are horizontally aligned and aligned with their centers aligned. . A heat insulating cap 27 is formed between the lower end plate 24 of the boat 22 and the seal cap 21.
[0023]
On the other hand, on the outside of the process tube 12, a cylindrical bell jar 30 made of stainless steel and having a diameter larger than that of the process tube 12 and closed at the upper end is concentrically covered. A plurality of reflecting members 31 formed of an annular concave mirror using stainless steel are stacked adjacently. In FIG. 1, the reflecting member 31 is provided on a portion of the boat 22 corresponding to the wafer mounting position. If necessary, a reflecting member may be provided on the ceiling wall of the bell jar 30. A resistance heating member (hereinafter, referred to as a heater) 32 is helically laid between the process tube 12 and the bell jar 30, and heat rays emitted outward in the radial direction of the heater 32 are reflected by the reflection member 31. It is directed radially inward. The heater 32 is divided into a plurality of heater units, and these heater units are configured to be sequenced independently and independently by a temperature controller (not shown). Outside the bell jar 30, a cylindrical heat insulating tank 34 whose upper end is closed is arranged concentrically, and the bell jar 30 and the heat insulating tank 34 are vertically supported by a gantry 33 constructed on the housing 10.
[0024]
A cooling air passage 36 for flowing a cooling air 35 such as nitrogen or air as a cooling medium is formed between the heat insulating tank 34 and the process tube 12 so as to entirely surround the process tube 12. . An air supply pipe 37 for supplying the cooling air 35 to the cooling air passage 36 is connected to a lower end portion of the heat insulating tank 34, and the cooling air 35 supplied to the air supply pipe 37 is diffused to the entire circumference of the cooling air passage 36. It has become. An exhaust port 38 for discharging the cooling air 35 from the cooling air passage 36 is opened at the center of the ceiling wall of the heat insulating tank 34, and an exhaust pipe (not shown) is connected to the exhaust port 38.
[0025]
A nitrogen gas supply pipe 40 for supplying a nitrogen gas 39 as an inert gas is inserted into the gantry 33 so as to supply the nitrogen gas 39 to a space between the bell jar 30 and the process tube 12. At another place, a nitrogen gas exhaust pipe 41 for exhausting the nitrogen gas 39 is inserted so as to exhaust the nitrogen gas 39 from the space between the bell jar 30 and the process tube 12.
[0026]
Next, the operation of the CVD apparatus having the above configuration will be described.
[0027]
Before the heater 32 is driven to heat, the nitrogen gas 39 is supplied to the space between the bell jar 30 and the process tube 12 from the nitrogen gas supply pipe 40 and exhausted from the nitrogen gas exhaust pipe 41, thereby allowing the nitrogen gas 39 to flow in advance. Is done. By maintaining the flow of the nitrogen gas 39, oxidation of the bell jar 30 and the reflection member 31 due to the heating of the heater 32 laid in the space between the bell jar 30 and the process tube 12 is prevented.
After the space between the bell jar 30 and the process tube 12 is filled with nitrogen gas, the supply and exhaust of nitrogen gas may be stopped as appropriate.
[0028]
As shown in FIG. 1, the boat 22 in which a plurality of wafers 1 are aligned and held is placed on the seal cap 21 in a state where the direction in which the wafers 1 are lined up is vertical, and is raised by the boat elevator 55. Then, it is carried into the processing chamber 11 from the boat loading / unloading port 19 (boat loading), and is left in the processing chamber 11 while being supported by the seal cap 21.
[0029]
Subsequently, the processing chamber 11 is evacuated to a predetermined pressure (0.1 to 100 Pa) by the exhaust pipe 17, and the processing chamber 11 is heated to a predetermined temperature (700 to 1000 ° C.) by the heater 32. At this time, among the heat rays emitted from the heater 32, the heat rays directed outward in the radial direction are reflected by the reflecting member 31 installed on the radially outer side and directed radially inward. Therefore, all the heat rays emitted from the heater 32 irradiate the process tube 12 to heat the processing chamber 11. Moreover, since the outer peripheral surface of the process tube 12 is coated with the silicon carbide film 14, the heat rays applied to the process tube 12 are efficiently absorbed by the process tube 12 and heat the processing chamber 11 effectively.
[0030]
Next, a processing gas is introduced into the upper end of the processing chamber 11 at a predetermined flow rate by the gas introduction pipe 18. The processing gas introduced into the upper end of the processing chamber 11 by the gas introduction pipe 18 flows down the processing chamber 11 and is exhausted from the exhaust pipe 17 to the outside of the processing chamber 11. The processing gas contacts the wafer 1 held by the boat 22 while flowing down the processing chamber 11 to form a CVD film on the wafer 1 by a thermal CVD reaction.
[0031]
After a predetermined film formation time has elapsed, after the introduction of the processing gas is stopped, a nitrogen gas as a purge gas is introduced into the processing chamber 11 from the gas introduction pipe 18, and the processing chamber 11 is exhausted by the exhaust pipe 17. . At this time, the cooling air 35 is supplied to the cooling air passage 36 between the bell jar 30 and the heat insulating tank 34, and is circulated by being supplied from the air supply pipe 37 and exhausted from the exhaust port 38. Since the cooling air 35 flowing through the cooling air passage 36 comes into contact with the outer surface of the bell jar 30 to remove the heat of the bell jar 30, the bell jar 30 is rapidly cooled. When the bell jar 30 is rapidly cooled, the temperature of the processing chamber 11 is rapidly lowered, so that the cooling time of the processing chamber 11 is reduced. At this time, the cooling air 35 flowing through the cooling air passage 36 directly contacts the outer surface of the bell jar 30, but does not contact the inner surface of the bell jar 30 and the outer surface of the reflection member 31 and the process tube 12 in which the processing chamber 11 is formed. . Therefore, even when the atmosphere is used for the cooling air 35, the oxidation of the inner surface of the bell jar 30 can be prevented. In addition, by flowing nitrogen through the space between the bell jar 30 and the process tube 12 together with the cooling by the flow of the cooling air 35, the cooling effect is further promoted.
[0032]
When the processing chamber 11 is purged with nitrogen gas and cooled to a predetermined temperature, the boat 22 supported by the seal cap 21 is lowered by the boat elevator 55 so that the processing chamber 11 Out of the boat (boat unloading).
[0033]
Thereafter, by repeating the above operation, the CVD apparatus 2 performs a batch process on the wafer 1 by the thermal CVD reaction.
[0034]
According to the embodiment, the following effects can be obtained.
[0035]
1) By installing a reflecting member for reflecting the heat of the heater to the process tube side on the inner surface of the bell jar outside the heater, the heat of the heater is all directed to the process tube side by the reflecting member, and the heat energy of the heater is efficiently used. Since it can be supplied to the processing chamber well, the time required to raise the temperature of the processing chamber can be shortened.
[0036]
2) By supplying cooling air from the air supply pipe to the cooling air passage between the bell jar and the heat insulating tank, exhausting the cooling air from the exhaust port, and circulating the cooling air, the inside of the bell jar can be rapidly cooled. The cooling time can be shortened.
[0037]
3) According to the above 1) and 2), the time for raising and lowering the temperature of the processing chamber can be shortened, so that the performance and throughput of the CVD apparatus can be increased, and the production of recent shallow junction ICs can be realized. .
[0038]
4) By connecting the nitrogen gas supply pipe and the nitrogen gas exhaust pipe to the space between the process tube and the bell jar, the nitrogen gas can flow through the space between the process tube and the belt. Can prevent oxidation of the bell jar and the reflection member laid in the space between the heater and the heater by heating, and the bell jar and the reflection member can be made of stainless steel.
[0039]
5) By coating the outer peripheral surface of the process tube with a silicon carbide film, the heat ray of the heater applied to the process tube can be efficiently absorbed by the process tube, so that the processing chamber can be heated more effectively. Can be.
[0040]
Note that the present invention is not limited to the above-described embodiment, and it goes without saying that various changes can be made without departing from the gist of the present invention.
[0041]
For example, the bell jar and the reflecting member are not limited to being made of stainless steel, but may be made of other materials. Further, the bell jar may be omitted and only the reflection member may be provided.
[0042]
The process tube is not limited to being formed using quartz glass, and may be formed using silicon carbide.
[0043]
The cooling medium is not limited to cooling air, but may be an inert gas such as nitrogen gas.
[0044]
Although the case of film formation has been described in the above embodiment, the present invention is used not only for oxidation treatment and diffusion treatment and diffusion but also for general heat treatment such as reflow and annealing treatment for carrier activation and planarization after ion implantation. Can be.
[0045]
The present invention can be applied not only to the batch type vertical hot wall type CVD apparatus but also to the whole substrate processing apparatus such as a batch type horizontal type CVD apparatus, a vertical type and a horizontal type hot wall type reduced pressure CVD apparatus, and other heat treatment apparatuses.
[0046]
【The invention's effect】
As described above, according to the present invention, the time for raising and lowering the temperature of the substrate processing apparatus can be reduced.
[Brief description of the drawings]
FIG.
1 is a front sectional view showing a vertical reactor of a CVD apparatus according to an embodiment of the present invention.
FIG. 2
FIG. 3 is an enlarged partial cross-sectional view showing a main part thereof.
FIG. 3
1 is a perspective view showing a CVD apparatus according to one embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Wafer (substrate), 2 ... CVD apparatus (substrate processing apparatus), 10 ... Housing, 11 ... Processing chamber, 12 ... Process tube, 13 ... Furnace port, 14 ... Silicon carbide film, 15 ... Seal ring, 16 ... Manifold, 17: exhaust pipe, 18: gas inlet pipe, 19: boat loading / unloading port, 20: seal ring, 21: seal cap, 22: boat, 23, 24: end plate, 25: holding member, 26: holding groove , 27 ... heat insulating cap part, 30 ... bell jar, 31 ... reflecting member, 32 ... heater (resistance heating member), 33 ... gantry, 34 ... heat insulating tank, 35 ... cooling air (cooling medium), 36 ... cooling air passage (cooling) Medium flow passage), 37 ... air supply pipe, 38 ... exhaust port, 39 ... nitrogen gas (inert gas), 40 ... nitrogen gas supply pipe, 41 ... nitrogen gas exhaust pipe, 50 ... cassette transfer unit, 51 ... cassette shelf, 52 ... Equipment cassette shelf, 53: cassette transporter, 54: wafer transfer machine, 55: boat elevator, 56: vertical reactor, 57: cassette, 58: cassette stage, 59: wafer attitude matching machine, 60: robot arm, 61: arm, 62: wafer holding part, 63: wafer holding plate.

Claims (1)

A process tube having a processing chamber for accommodating a substrate, a resistance heating member installed to surround the process tube and heating the substrate, and a heat insulating tank installed outside the resistance heating member are provided. In substrate processing equipment,
A reflection member for reflecting the heat of the resistance heating member to the process tube side is provided between the resistance heating member and the heat insulation tank, and a cooling medium is provided between the reflection member and the heat insulation tank. A substrate processing apparatus, wherein a cooling medium flow passage that circulates is formed.

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