JP2003100643A - High temperature cvd system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a high temperature CVD system in which a plurality of sheets of wafer can be heat treated simultaneously under a high temperature. SOLUTION: The high temperature CVD system comprises a reaction chamber 53, means for supplying cooling water to a double quartz tube forming the reaction chamber 53, a heating coil 56 disposed on the outer circumference of the reaction chamber, means 46 for evacuating the reaction chamber, means for supplying gas to the reaction chamber, and a susceptor 54 being induction heated by a heating coil, a jig 72 for fixing a plurality of susceptors to the reaction chamber 53 at a required interval in the vertical direction, a plurality of susceptors 54 for supporting a wafer fixed to the intermediate part of the susceptor fixing jig 72, one through a plurality of dummy susceptors 54a provided above and below the susceptors 54 for supporting a wafer 76, and a gas supply pipe 79 having a plurality of small holes 80 for supplying gas between respective susceptors.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to high temperature CVD for heating a susceptor in a reaction chamber to a high temperature by a high frequency induction heating method.
The present invention relates to a high temperature CVD (Chemical Vapor Dep
osition) device.

[0002]

2. Description of the Related Art As an example of the prior art of a high frequency induction heating apparatus for simultaneously heating a plurality of wafers at a high temperature in an inert gas atmosphere or in a vacuum, an apparatus as shown in FIG. 4 is known. In this conventional high-frequency induction heating device, a dome-shaped opaque quartz perger 2 is provided on a base 1 so that a reaction chamber 4 in a closed space is formed by using an O-ring 3 or the like. A spiral (mosquito coiling) high-frequency induction coil 5 is fixedly arranged in the. Further, a pipe-shaped shaft body 6 is provided from the base 1 through the central portion of the high-frequency induction coil 5, and a flange portion 7 is formed at an upper end portion of the pipe-shaped shaft body 6, and the flange portion is formed. A disk-shaped susceptor 8 having an insertion hole 9 in the center thereof is fixed to 7.

A pulley 10 is provided below the base 1 of the pipe-shaped shaft body 6, and the pulley 10 is connected by a belt 12 from a rotary shaft of a motor 11 provided on the lower surface of the base 1 so as to connect the motor 11 with the belt. Drive-controlled pipe 6
The susceptor 8 is rotated in the vicinity of the upper surface of the high frequency induction coil 5 together with the rotation. Further, the pipe-shaped shaft body 6 serves as a gas introduction portion from an inert gas storage portion (not shown) to the Pelger 2, and the SI wafer 13 mounted on the rotating susceptor 8 has a high temperature. The gas is made to act in the state. In addition,
Provided between the spiral high-frequency induction coil 5 and the susceptor 8 is a donut disk-shaped coil cover 15 in which a bent portion 14 is formed on the lower side. In addition, foundation 1
There is an exhaust hole 16 for exhausting gas or exhausting gas for vacuum suction. The gas is jetted upward from the pipe-shaped shaft body 6 and acts on the wafer 13 from above as shown by an arrow 17.

Another example of the prior art is an apparatus for placing a wafer on the surface of a graphite pyramid and heating it as shown in FIG. That is, a dome-shaped quartz perger 22 inverted from below is fixed to a base plate 21 provided on the upper surface by an O-ring 23 so that a reaction chamber 24 is formed. In the reaction chamber 24, a rotating shaft 26 for transmitting the rotation of a motor 25 installed on the upper surface of the substrate 21 is provided with 6 to 8
A susceptor 27 made of a graphite pyramid on the surface is rotatably provided. The SI wafer 28 is placed on each inclined surface of the graphite pyramidal susceptor 27, and the inert gas is supplied from the gas supply units 30 provided on the left and right sides of the lower surface of the base plate 21. SI wafer 28 is heated by a large number of infrared lamps 29 arranged on ~ 6 surfaces.
The gas is made to act on. In addition, the gas exhaust hole 3
1 is provided in the lower part of the Pellger 22.

[0005]

However, in the heating structure of the susceptor 8 or 27 shown in FIG. 4 or 5 described above, the spiral high-frequency induction coil 5 is arranged on the lower surface of the susceptor 8 and the susceptor 8 is heated. There are a planar heating type that heats the wafer 13 placed on the upper surface, and a barrel type that places the SI wafer 28 on the inclined surface of the graphite pyramidal susceptor 27 and heats it by the infrared lamp 29. Radiation loss is large and there is a problem in practical use, and the heating temperature is up to about 1300 ° C.
It is not suitable for a high temperature CVD apparatus that heats at ℃.

[0006]

High temperature CVD according to the present invention.
The apparatus comprises a double quartz tube forming a reaction chamber, cooling water supply means for supplying cooling water into the double quartz tube, and a heating coil spirally wound around the outer circumference of the double quartz tube. A high temperature CVD apparatus comprising: an evacuation means for bringing the reaction chamber into a vacuum state; a gas supply means for supplying a gas to the reaction chamber; and a susceptor provided in the reaction chamber which is induction-heated by the heating coil. A susceptor mounting jig that holds a plurality of the susceptors at predetermined intervals in the vertical direction in the reaction chamber, a plurality of wafer-supporting susceptors mounted in an intermediate portion of the susceptor mounting jig, and the susceptor mounting One or a plurality of dummy susceptors provided above and below a plurality of susceptors provided for supporting the wafer of the jig, and an outer peripheral side surface of the plurality of susceptors. Provided in a direction, it is characterized in that a gas supply pipe having a plurality of small holes for supplying gas to between the respective susceptor.

[0007]

FIG. 1 is a schematic configuration diagram of a high temperature CVD apparatus according to the present invention. A heating section 41 is provided on the upper left side, a wafer loading / unloading section 42 is provided below the heating section 41, and further below the heating section 41. The heating unit 41 is provided with a susceptor, which will be described later, and a drive unit 43 for raising or lowering the wafer. On the upper right side of the heating unit 41, a supporting column 4 for supporting the heating unit
4 is provided, and a connection part 45 to the vacuum exhaust device is provided below the connection part 4.
Further, a vacuum exhaust device 46 and a motor 47 for driving the drive unit 43 for controlling the raising and lowering of the susceptor and the like are provided in the lower portion thereof. The vacuum exhaust device 4
6 is communicated with the heating section 41 from the connecting section 45 through the sample loading / unloading section 42.

The above-mentioned heating unit 41 is a cooling water supply unit 48.
Cylindrical water-cooled double quartz tube 5 equipped with a cooling water drain 49
0, an upper flange 51 provided on the upper portion thereof, and a lower flange 52 provided on the lower portion thereof form a reaction chamber 53 which is a closed space inside the water-cooled double quartz tube 50. In the reaction chamber 53, a plurality of disk-shaped susceptors 54 made of thin graphite for mounting or supporting a wafer are placed.
Are provided in a stepwise manner in the vertical direction at required intervals and are arranged as a susceptor assembly. Further, a heat insulating material 55 made of graphite felt is installed around the susceptor assembly and on the upper and lower flanges 51 and 52 to suppress heat radiation in the reaction furnace 53.

A heating coil 56 for high-frequency induction heating of the susceptor 54 and the wafer mounted or supported on the susceptor 54 is spirally wound around the water-cooled double quartz tube 50, and is connected to a power source (not shown). It is connected. Also,
The upper flange 51 is provided with a gas supply unit 57 for gas supplied from a gas generation unit (not shown). The plurality of susceptors 54 arranged in the heating unit 41 are configured to be raised and lowered by a motor 47 for moving up and down together with a support base 58 thereof. That is, the support base 58 is
It is fixed to a moving table 60 that moves in the vertical direction by a pipe-shaped support tube 59. One of the left and right sides (left side) of this moving table 60 is fitted into a non-rotating guide shaft 61, and the other (right side) is An engagement portion 62 having an inner peripheral surface provided with a spiral female screw is screwed and supported by a drive shaft 63 having a spiral groove formed on the outer peripheral surface.

A gear 64 is provided at the lower end of the drive shaft 63. The gear 4 is provided on the rotary shaft of the motor 47 either directly or through a speed reducer to engage the gear 4 with the gear 64.
The rotation of the movable table 60 is controlled by controlling the rotation of the motor 47. Further, the rising or lowering stop position of the moving table 60 can be controlled by operating a micro switch provided on a side edge of the driving unit 43 when the moving table 60 moves to a predetermined position. The illustrated state shows a state in which the susceptor 54 is raised to a position where it can be heated by the heating unit 41.

Further, the movable table 60 has a pipe-shaped support tube 59 fixed to the support table 58 of the plurality of susceptors 54.
A motor 66 for rotating the motor is provided. A pulley 67 provided directly or via a speed reducer on the rotating shaft of the motor 66 for rotation and a pulley 68 provided at the lower end of the pipe-shaped support tube 59 are connected by a belt 69. By controlling the rotation of the susceptor 54
The support base 58 can be rotated. Reference numeral 70 denotes a stretchable SUS bellows cover, and 71 denotes a sample loading / unloading portion of the wafer or the susceptor 54.

Next, the structure of the heating section 41 constituting the reaction furnace will be described with reference to the embodiment shown in FIG. The outer circumference of the heating section 41 is formed by a cylindrical water-cooled double quartz tube 50, and the cooling water supplied from the cooling water supply section 48 below is
The cooling water is drained from the cooling water drain portion 49 so as to pass through the entire circumference of the water-cooled double quartz tube 50. In this embodiment, the cooling water supply part 48 and the cooling water drain part 49 are provided at one location, respectively, but a plurality of locations may be provided if necessary. Inside the water-cooled double quartz tube 50, a heat insulating material 55 made of graphite felt is used.
Is provided to suppress heat radiation and improve thermal efficiency. This heat insulating material 55 may be provided using a tantalum plate so as to surround it in a double or triple manner in a partition shape.

Inside the heat insulating material 55, the pipe-shaped support tube 5 is provided.
A susceptor mounting jig 72 composed of a support column 73, an upper fixing plate 74, etc. is installed on a support base 58 fixed to 9. Support pillar 7 of this susceptor mounting jig 72
As shown in the side sectional view of FIG. 3 (a) and the bottom view of FIG. 3 (b), the susceptor 54 is attached to the three columnar support columns 73 with a plurality of grooves at required intervals. 75 is provided, and the disc-shaped susceptor 54 is inserted into the groove 75. The susceptor 54 in this embodiment has a support portion 7 having an L-shaped cross section for supporting the wafer 76 on its lower surface.
7 are formed. In this support portion 77, the L-shaped support portion 77 is not formed in a predetermined range on the insertion side so that the disk-shaped wafer 76 can be easily taken in and out. The support range of the wafer 76 with respect to the support section 77 can be widened by increasing the inner diameter of the support section 77 with respect to the outer diameter of the wafer 76 and lengthening the L-shaped lower support section.

The susceptor 54 is mounted on the susceptor mounting jig 72 by mounting the susceptor 54 in the groove 75 of the support column 73.
However, when the support base 58 of the susceptor 54 is lowered to perform work on the sample loading / unloading portion 71, the wafer 76 is inserted into the susceptor 54 with the susceptor 54 mounted on the support column 73. Alternatively, after inserting the wafer 76 into the susceptor 54, the susceptor 54
Which method is to be attached to the support column 73 may be selected according to the work procedure before and after. After the susceptor 54 in which the wafer 76 is inserted is mounted on the support column 73 of the susceptor mounting jig 72, a detachable holding column 78 is mounted on the support base 58 and the upper fixing plate 74, and the wafer 76
Alternatively, the mounting of the susceptor 54 is stabilized.

Susceptor 5 to susceptor mounting jig 72
For mounting No. 4, one or a plurality of dummy susceptors 54a are mounted on the upper end and the lower end, respectively, and the susceptor 54 on which the wafer 76 is supported is arranged in the middle thereof.
Further, the winding pitch of the heating coil 56 is adjusted by roughening the middle of the winding portion and making the upper and lower ends dense.
The temperature distribution in the vertical direction of the reaction furnace can be made uniform.
In this embodiment, the dummy susceptors 54a at the upper and lower ends are provided with the same shape as the susceptor 54 for supporting the wafer 76, but for example, a flat plate-like one having no portion for supporting the wafer 76 is provided. You may

The susceptor mounting jig 72 is mounted on the support base 58 as described above, and the motor 66 installed on the moving base 60 is rotated to rotate the support base 58.
Can be rotated to stabilize the heating of the wafer 76 together with the susceptor 54 by the heating coil 56. Further, the wafer 76 is provided so as to be supported on the lower surface of the susceptor 54. This is flakes (fine dust particles) due to the reaction action of gas in the reaction furnace.
In order not to adhere to the surface of the wafer 76,
Although the wafer 75 is supported on the lower surface, the wafer 75 may be supported on the upper surface of the susceptor 54 when the generation of flakes has almost no effect.

Next, although not explicitly shown in FIG.
As shown in FIG. 2, the susceptor 54 has the structure of the present invention.
A rod-shaped gas nozzle 79 is provided vertically on the outer peripheral side. The gas nozzle 79 is connected to the gas supply unit 57, and a small gas supply hole 80 is provided between the upper susceptor 54 and the lower susceptor 54. The gas supply hole 80 is provided in the susceptor 54.
It is preferable that the gas is supplied toward the center of the susceptor 54 and the gas is supplied between the plurality of susceptors 54. Further, although not shown, the gas nozzle 79 can be rotated by a motor in a predetermined angle range in a predetermined cycle to change the direction of gas supply and adjust the in-plane film thickness distribution of the wafer 76. it can.

Reference numeral 81 in FIG. 2 denotes a gas exhaust port, and the vacuum exhaust device 4 is connected via the vacuum exhaust device connecting portion 45.
6 is exhausted. Further, the pressure inside the reaction furnace can be controlled by using the vacuum exhaust device 46 in which the flow rate control valve is provided in the gas introduction part.
Thereby, it can be used as a low pressure CVD apparatus.

[0019]

The high temperature CVD apparatus according to the present invention has the following effects. (1) In the present invention, since the side end surface of the wafer serves as a heat dissipation surface, the heat dissipation area is extremely small, heat dissipation is suppressed, and thermal efficiency is good. Further, by providing the heat insulating material, the thermal efficiency is further enhanced. (2) Further, in order to correspond to the temperature distribution in the vertical direction in the reactor, the temperature distribution is made uniform by providing dummy susceptors at the top and bottom. Further, the temperature distribution can be further adjusted by adjusting the pitch between the windings of the heating coil or by rotating the wafer. (3) Provide a nozzle for gas supply with a small hole in the vertical direction,
Moreover, since the direction of the gas nozzle can be changed, the film pressure distribution in the wafer surface can be adjusted.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional configuration diagram showing an overall structure of a high temperature CVD apparatus according to the present invention.

FIG. 2 is a cross-sectional view of a heating part of a high temperature CVD apparatus which is a main part of the present invention.

FIG. 3 is a schematic view showing a mounting structure of a susceptor and a wafer to a susceptor mounting jig of a heating unit according to the present invention.

FIG. 4 is a cross-sectional view of a conventional planar heating type high frequency induction heating device for heating a plurality of wafers.

FIG. 5 is a cross-sectional view of a conventional heating device using a solenoid type heating coil using graphite pyramids for heating a plurality of wafers.

[Explanation of symbols]

1,21 base 2,22 Quartz Perger 3,23 O-ring 4,24,53 Reaction chamber 5 high frequency induction coil 6 Pipe-shaped shaft 7 collar part 8, 27, 54 susceptor 9 insertion holes 10 pulley 11,25,47,66 motor 12,69 belt 13,28 SI wafer 15 coil cover 16 Exhaust hole 29 infrared lamp 30,57 Gas supply section 31 exhaust port 41 heating part 42 Wafer loading / unloading section 43 Drive 44 props 45 connection 46 Vacuum exhaust system 48 Cooling water supply section 49 Cooling water drain 50 Water-cooled double quartz tube 51 upper flange 52 Lower flange 54a dummy susceptor 55 Thermal insulation 56 heating coil 58 Support 59 Pipe-shaped support tube 60 mobile platform 61 Guide shaft 63 drive shaft 64, 65 gears 67,68 pulley 70 Expandable SUS Bellows Cover 71 Sample entry / exit 72 Susceptor mounting jig 73 Support pillar 74 Upper fixing plate 75 Support post groove 76 wafers 77 Susceptor support 78 Holding pillar 79 gas nozzle 80 gas supply hole 81 Gas exhaust port

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3K059 AB04 AB22 AD03 AD05 AD07                       CD52                 4K030 CA04 EA08 FA10 GA06 KA04                       KA23 LA15                 5F045 AA06 AF19 DP19 DQ05 EC02                       EF03 EF10 EJ04 EJ09 EK03                       EK21 EM02 EM08 EM10 EN04

Claims (5)

[Claims] 1. A double quartz tube forming a reaction chamber, cooling water supply means for supplying cooling water into the double quartz tube, and a heating coil spirally wound around the outer circumference of the double quartz tube. High temperature CVD comprising: a vacuum evacuation unit for bringing the reaction chamber into a vacuum state; a gas supply unit for supplying gas to the reaction chamber; and a susceptor provided in the reaction chamber that is induction-heated by the heating coil. In the apparatus, a susceptor mounting jig that holds a plurality of the susceptors at predetermined intervals in the vertical direction in the reaction chamber, a plurality of wafer-supporting susceptors mounted in an intermediate portion of the susceptor mounting jig, One or a plurality of dummy susceptors provided above and below the plurality of susceptors provided for supporting the wafer of the susceptor mounting jig, and the outside of the plurality of susceptors. Provided in the longitudinal direction of the side surface,
A high temperature CVD apparatus comprising: a gas supply pipe having a plurality of small holes for supplying a gas between the susceptors. 2. The high temperature CVD apparatus according to claim 1, wherein a heat insulating material is provided on the peripheral surface and the upper and lower surfaces of the reaction chamber. 3. The high temperature CVD apparatus according to claim 1, wherein the susceptor mounting jig that holds the susceptor is configured to rotate or rotate. 4. The high temperature CVD apparatus according to claim 1, wherein the gas supply pipe having a plurality of small holes for supplying the gas is configured to rotate or rotate. 5. The high temperature CVD according to claim 1, 2, 3 or 4, wherein a wafer supporting portion capable of supporting the wafer in a retractable manner is formed on a part of an outer peripheral side edge of a lower surface of the susceptor.
apparatus.