JPH0265126A - Dispersing device - Google Patents

Abstract

PURPOSE:To provide a wafer face and prism face in parallel by fixing a quartz prism on the part in which a part of a circular plate of the same shape as a wafer is cut to place the circular plate on a boat. CONSTITUTION:A part of a cut quartz glass circular plate 17 of the same outer diameter as that of a wafer 2 is welded on a stopper 18. Prisms 20, 20 are sandwiched between prism holding plates 19, 19 and the upper prism 20 is fixed on the cut part of the circular plate 17 to make a face parallel to the circular plate 17. The wafer 2 is placed on a support bar 16 constituting a part of a boat. Thereby radiant light outgone from a point 21 on the wafer 2 is bent by the prisms 20, 20 to enter into a radiation measuring device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a diffusion device for semiconductor manufacturing, and more particularly to a structure suitable for positioning a wafer and a prism in order to accurately measure the temperature of the wafer.

[Conventional technology]

In the conventional apparatus, the position of the quartz prism is determined by holding the quartz prism in a holding tube, as described in Japanese Patent Application Laid-Open No. 62-105419.

[Problem to be solved by the invention]

The above conventional technology does not take into account the fact that the wafer surface and the prism surface are arranged in parallel, and there is a problem that when measuring radiation from the wafer surface, excess radiation that becomes measurement noise is introduced into the prism surface. Ta.

An object of the present invention is to provide a prism holding structure in which a wafer surface and a prism surface are installed in parallel.

[Means to solve the problem]

In order to achieve the above purpose, a disk with the same shape as the wafer is used, and a quartz prism is fixed in the cutout part.
In the same way as placing a wafer on a boat, simply placing one circular plate makes the wafer surface and prism surface parallel.

[Effect]

The notched disk has the same shape as the wafer, so when placed on a boat, the disk is almost parallel to the wafer surface.

Also, the prism surface welded to the disc notch is carefully welded so that the prism surface and the disc are parallel to each other. Therefore, when a circular plate with several notches is placed on a boat, the parallelism between the wafer surface and the prism surface can be easily ensured.

〔Example〕

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

FIG. 1 is a schematic diagram of a diffusion device to which the present invention is applied. In this figure, 1 is a quartz tube, and a boat 3 in which a plurality of wafers 2 (for example, 50 to 150 wafers) are placed is moved into and out of the quartz tube 1 by a fork 4. The wafer 2 inside the quartz tube 1 is heated by a heater 5 installed outside the quartz tube 1. Between the heater 5 and the quartz tube 1,
Uniform heating that makes the wall temperature distribution uniform so that it is suitable for uniform heating? 1 to 6 (there are also diffusion devices that do not have a soaking tube 6).

Quartz'l? , L, when oxidizing and diffusing the wafers 2, a processing gas is introduced into the quartz tube 1 from the processing gas lower part.

The radiant light from the wafer 2 that has passed through the light guide 8 is collected by an objective lens 9 outside the reaction tube, passes through an optical fiber 10, and is converted into temperature by a radiant light temperature converter 11. This temperature signal enters the diffuser control section 12 and, together with the signal from the hot pair 14, operates the heat generation amount control section 13 of the heater 5.

FIG. 2 is a detailed view of the light guide used in the present invention. In this figure, the wafer 2 is placed on a support bar 16 that forms part of the boat. 17 is a quartz glass disk with a notch, and a stopper 18 is welded at one location in the circumferential direction. The notched quartz glass disk 17 is made to have the same thickness and outer diameter as the wafer 2 (the thickness may be larger than the wafer 2), and is placed on the support bar 16 in the same way as the wafer 2. By doing so, it can be placed parallel to the wafer surface. A part of the notched quartz glass disk 17 is cut out, and a prism holding plate 19, 19 is welded to that part. A prism 20 is sandwiched between the prism holding plates 19 and 19'. Prism 20. Prism holding plate 19.1
When welding the prism 9 to the notched quartz glass disk 17, one surface of the prism is welded parallel to the notched quartz glass disk 17.

In this way, the radiation light emitted from one point 21 on the wafer 2 is bent by the prism 20.

It advances in the order of 22, 22' and 22' and reaches the objective lens 9 in FIG.

By changing the position of the stopper 18 in the circumferential direction, the circumferential position of the radiation light 22' from the wafer 2 can be changed, and as shown in FIG. It becomes possible to take out the radiant light from each location to the outside without interfering with each other.

In order to avoid metal contamination on the wafer 2, the parts shown in FIG. 2, except for the wafer 2, are made of quartz glass, silicon carbide (SiC), or polysilicon.

Although only one objective lens 9 is shown in FIG. 1, a plurality of objective lenses 9 may be provided.

〔Effect of the invention〕

Since the present invention is configured as described above, it produces the effects described below.

The notched quartz glass disk has the same shape as the wafer, and can be placed on a boat (support bar) in the same way as the wafer in one step. Therefore, the wafer surface and the prism surface can be easily made parallel, and excess radiation light (noise) is not introduced into the objective lens.

As a result of the above, the prism surface and the wafer surface can be easily made parallel, and the wafer temperature sub-chamber error can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional perspective view showing an embodiment of the apparatus of the present invention, and FIG. 2 is a perspective view showing the configuration of a light guide used in the present invention. 1...Quartz tube, 2...Wafer,;3...Boat, 4
...Fork, 5... Heater, 6... Soaking tube, 7
... Processing gas population, 8... Light guide, 9... Objective lens, 10... Optical fiber, 11... Radiant light temperature converter, 12... Diffusion device control unit, 13... - Heater plate of heater, 14... thermocouple. 16... Support bar, 17... Quartz glass disc with notch, 18... Stopper, 19... Prism holding plate, 2
0...prism. 71--Material factory entrance 14-11 Outside light

Claims (1)

[Claims] 1. A quartz tube and a plurality of wafers installed in the quartz tube,
It has a heater that heats from outside the quartz tube, a light guide consisting of a prism for bending light and its holding material, an objective lens and a diaphragm installed outside the entrance of the quartz tube, and a lens and an aperture installed next to the quartz tube. The radiant light from the wafer is bent using the light guide and guided out of the entrance of the reaction tube, and is then directed to the optical fiber using an objective lens and a diaphragm. In a diffusion device that detects the wafer temperature by transmitting it to a radiation thermometer and determines the amount of heat generated by the heater based on the temperature indication value, the light guide is made of a solid shape and the same diameter as the wafer. By cutting out a part of the disk and fixing it by welding, and placing the disk on a boat in the same manner and procedure as the wafer, the wafer surface and the prism surface of the light guide can be made parallel (or at a predetermined angle). A diffusion device characterized by holding.