JPS5915070Y2 - Holder used for chemical vapor deposition equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a holder suitable for chemical vapor deposition of thin films with uniform thickness.

Chemical vapor deposition methods, especially vapor phase epitaxial growth methods, are
It is widely used in the manufacture of semiconductor devices such as light emitting diodes, FETs, and Gunn diodes.

When an epitaxial film is grown on the surface of a single-crystal wafer by a vapor phase epitaxial growth method, an apparatus such as the one shown in the first part is used.

That is, in FIG. 1, reference numeral 1 denotes a horizontal gas phase reactor used for manufacturing GaAs epitaxial wafers.

2 is a holder, 3 is a holder support rod, 4 is a Ga boat,
5 and 6 are reaction gas introduction pipes, and 7 is an exhaust pipe.

When an epitaxial film is grown in vapor phase using the apparatus shown in Fig. 1, the thickness of the epitaxial film obtained is not uniform, and for example,
In the case of a GaAs1-xPx epitaxial film with a film thickness of 0 μm, the film thickness at the upstream side of the wafer's airflow tends to be up to three times thicker than other parts, which affects the yield during device manufacturing. This was the cause of the decline.

It is thought that this phenomenon occurs because the concentration of components in the gas phase decreases on the downstream side of the airflow, and as a result, the epitaxial growth rate decreases.

The inventors of the present invention arrived at the present invention as a result of intensive research in order to produce an epitaxial film with a uniform film thickness.The purpose of the present invention is to produce an epitaxial film with a uniform film thickness. The objective is to provide a new holder suitable for

The above-mentioned object of the present invention is to provide a chemical system comprising a susceptor on which a wafer is placed, a sleeve that holds the susceptor, and a drive shaft that rotates the susceptor and the sleeve so that their rotational directions are not included in the same plane. This is achieved by a holder used in a vapor deposition device.

Next, the holder according to the present invention will be explained in more detail based on the drawings.

FIG. 2 is a perspective view of a specific example of the holder according to the present invention.

In FIG. 2, 8 is a sleeve, and 9 is a susceptor on which a wafer is placed.

It is desirable that a plurality of susceptors 9 be attached to the rotating shaft 10.

The rotating shaft 10 has a bearing 11 provided on the inner surface of the sleeve 8.
It is rotatably held by.

By adjusting the position where the bearing 11 is attached to the inner surface of the snowball 8, the susceptor 9 can be moved in the airflow direction (vertical direction in the figure).
can be tilted against.

The angle of inclination is preferably within 45° with respect to the direction of the airflow.

Further, the rotating shaft 10 is provided with a gear 12 .

The gear 12 rotates the ceptor 9 by engaging with a gear 15 provided at the tip of a drive shaft 13, which will be described later.

As these gears, bevel gears, spur gears, etc. can be selected as appropriate.

13 and 14 are dual drive shafts.

A gear 15 is provided on the inner shaft 13 of the drive shaft, and a gear 12
The susceptor 9 is rotated in a plane parallel to the direction of the airflow, or in a plane inclined from this plane as described above.

Further, the outer shaft 14 of the drive shaft is connected to the sleeve 8, and can rotate the sleeve 8 in a plane perpendicular to the direction of the airflow.

The holder is preferably manufactured using quartz, alumina porcelain, or the like.

Further, the bearing 11 may preferably be coated with BN (boron nitride) in order to smooth rotation.

Additionally, if an O-ring made of pyton rubber or the like is attached to the rotating part, the device can be kept airtight.

When placing a wafer on the susceptor 9, it is desirable to use a quartz clip to fix the wafer.

FIG. 3 is a perspective view of another example of the holder according to the present invention.

In FIG. 3, 16 is a susceptor, and 17 is a sleeve.

18 is a gear. The susceptor 16 and the gear 18 are attached to a rotating shaft 19, and the rotating shaft 19 is rotatably supported by a bearing 20 provided on the sleeve 17.

Gear 18 engages another gear 21 provided on sleeve 17 .

22 is a drive shaft that rotates the sleeve 17.

Further, 23 is a connecting portion between the sleeve 17 and the drive shaft 22.

The gear 21 is rotated by a fixed sleeve which will be described below.

That is, FIG. 4 is a perspective view of a fixing sleeve that supports the holder shown in FIG. 3 in an appropriate position within the reactor.

In FIG. 4, 24 is a fixed sleeve, and 25 is a pawl that engages with the gear 21.

26 is a support portion that supports the holder.

The outer diameter of the fixed sleeve 24 is smaller than the inner diameter of the sleeve 17, and its upper end is connected to the lower part of the sleeve 17 so as to be inserted thereinto.

When the sleeve 17 is rotated by the drive shaft 22, the claws 25
engages with the gear 2 and rotates, so that the gear 18 that engages with the gear 21 and the susceptor 16 rotate.

It is appropriate that about 1 to 2 to 4 claws 25 be provided on the outer periphery of the fixed sleeve 24.

In this case, the susceptor rotates intermittently.

The rotating shaft 19 can be tilted by appropriately adjusting the position of the bearing 20 using a spacer or the like.

The angle of inclination is 4 with respect to the direction of airflow (vertical direction of the drawing)
A value within 5° is appropriate.

The holders in the embodiments shown in FIGS. 3 and 4 are also suitably made of materials such as quartz and alumina porcelain.

Further, it is desirable that rotating parts such as the bearing 20 be coated with BN.

Note that the holder according to the present invention is not limited to the specific examples described in this specification.

Moreover, it can be used in both vertical and horizontal reactors.

By using the holder according to the present invention, epitaxial films such as GaAs, GaP, GaAs, xPX, etc., having a uniform film thickness can be deposited in a chemical vapor phase, thereby improving the yield of devices such as light emitting diodes. Therefore, its industrial utility value is extremely large.

[Brief explanation of the drawing]

FIG. 1 is a schematic longitudinal cross-sectional view of an example of a horizontal reactor. FIG. 2 is a schematic perspective view of a specific example of the holder according to the present invention. FIG. 3 is a schematic perspective view of another embodiment of the holder according to the present invention, and FIG. 4 is a schematic perspective view of a fixing sleeve. 1...Horizontal reaction device, 2...Holder, 3...Holder support rod, 4...Ga
Boat, 5...Reaction gas introduction pipe, 6...
...Reaction gas introduction pipe, 7...Exhaust pipe, 8...
... Sleeve, 9... Susceptor, 10.
... Rotating shaft, 11 ... Bearing, 12 ...
... Gear, 13 ... Drive shaft, 14 ...
・Drive shaft, 15... Gear, 16... Susceptor, 17... Sleeve, 18...
・Gear, 19... Rotating shaft, 20... Bearing, 21... Gear, 22... Drive shaft,
23... Connecting part, 24... Fixed sleeve, 25... Claw, 26... Supporting part.

Claims (1)

[Scope of utility model registration request] A holder used in a chemical vapor deposition apparatus, comprising a susceptor on which a wafer is placed, a sleeve for holding the susceptor, and a drive shaft for rotating the susceptor and sleeve so that their respective rotational directions are not included in the same plane.