JPH09219440A - Tray for wafer heating use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to maintain and ensure the flatness of a wafer placement surface without generating deformation in the wafer placement surface by a method wherein a tray for wafer heating use is constituted of a support plate, which has the flat upper surface to be placed with a wafer and consists of ceramics or a quarts, and metal clips for fixing the wafer on this support plate. SOLUTION: In a tray 3 for wafer heating use, the upper surface, on which a wafer 2 is placed, of the tray 3 is a flat surface which is not required a processing, and a support plate 4, which is provided with four straight line-shaped grooves 6 processed an intervals of 90 degrees in the peripheral direction of the flat surface and made of ceramic or a quartz, is provided on the outer periphery of the flat surface. Moreover, four pieces of metal clips 5 are provided in such a way as to correspond to the four grooves 6 provided in the plate 4. Straight line-shaped projections 7, which are respectively fitted in the four grooves 6, are respectively provided on the intermediate part of one piece on each upper side of those clips 5 and at the same time, handgrip parts 8 with an L-shaped section are respectively provided on each upper surface of the two pieces of the clips 5 among the clips 5. Thereby, deformation is never generated in the wafer 2 placement surface and flatness of the wafer 2 placement surface can be maintained and ensured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer heating tray in which wafers are placed and fixed and placed in a heating furnace in a wafer manufacturing process, a wafer processing process, and the like. The present invention relates to a wafer heating tray used when a curing furnace that requires heating and uniform heat distribution is used.

[0002]

2. Description of the Related Art In a semiconductor manufacturing process, a wafer is heat-treated for oxide film formation, thermal diffusion annealing treatment, sintering treatment, thermosetting treatment, or other curing process. In such a heating process, the wafer is mounted on the heating tray and mounted on the heater in the heating furnace.

FIG. 4 and FIG. 5 are external perspective views showing a wafer heating tray conventionally used in a curing furnace.

The wafer heating tray 30 of FIG. 4 is made by processing a metal plate 31 into a metal plate, and prevents the wafer 32 from being displaced at an interval of 90 degrees in the circumferential direction on the outer periphery of the mounting portion of the wafer 32. Then, the bent pieces 33 for fixing are provided, and two of the bent pieces 33 are further bent outward to constitute the handle 34.

The wafer heating tray 40 shown in FIG.
It is made by cutting a ceramic flat plate 41, and has a recess 43 at the center for mounting and fixing the wafer 42.

[0006]

However, according to the conventional wafer heating tray of FIG. 4 described above, since it is made of a metal material and has a shape that is easy to process, it is inexpensive, but the wafer mounting surface at the time of processing is low. It is difficult to secure the flatness of the wafer mounting surface and to maintain the flatness of the wafer mounting surface during heating in the curing furnace or repeated heating and cooling. Therefore, the tray for mounting and fixing the wafer in the curing furnace is warped, the heat distribution to the wafer is not uniform when the wafer is heated, and a high quality wafer cannot be obtained.

According to the conventional wafer heating tray of FIG. 5 described above, since the ceramic material is used, there is almost no expansion or contraction during heating in the curing furnace or repeated heating and cooling. The flatness of the mounting surface of the wafer can be maintained, the heat distribution becomes uniform when the wafer is heated, and a good quality wafer can be obtained. However, since it is necessary to form a concave portion for mounting and fixing the wafer on the mounting surface, the processing is troublesome, the processing cost becomes expensive, and the processing method is limited. was there.

The present invention has been made in view of the above-mentioned drawbacks of the prior art. It uses a supporting plate made of ceramic or the like that is not thermally deformed by heating in a curing furnace or by repeated heating and cooling, and it is not processed. It is an object of the present invention to provide a high-quality, low-cost wafer heating tray by performing simple processing with high workability.

[0009]

To achieve the above object, in the present invention, in a wafer heating tray in which a wafer is placed and fixed and placed in a heating furnace, the wafer heating tray is placed on the wafer heating tray. There is provided a wafer heating tray comprising a supporting plate made of ceramic or quartz whose upper surface is flat, and a metal clip for fixing the wafer on the supporting plate.

According to the above arrangement, the wafer can be placed and fixed by placing the wafer on the ceramic support plate and sandwiching and fixing the wafer with metal clips. This eliminates the need for processing for mounting and fixing the wafer on the ceramic flat plate, and allows the outer shape of the ceramic support plate to have a desired arbitrary shape. Also,
The ceramic support plate on which the wafer is placed does not undergo thermal deformation even by heating / cooling, the heat distribution in the heating furnace can be made uniform with respect to the wafer, and a high quality wafer can be obtained.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a preferred embodiment,
The metal clip is composed of a clip having a U-shaped cross section for clamping and fixing the wafer, a groove is provided on the outer periphery of the wafer mounting portion of the support plate, a projection is provided on one piece of the clip, and the projection is fitted into the groove. It is characterized in that the clip is locked.

In a further preferred embodiment, the metal clip is characterized in that the upper piece forming the U-shape is longer than the lower piece.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a heating furnace in which a wafer heating tray according to the present invention is placed. In this curing furnace 1, the wafer 2
Is fixed on the heating tray 3 and heated on the heater 4.

FIG. 2 is an external perspective view showing a specific example of the wafer heating tray 3 placed in the curing furnace 1 of FIG.

The wafer heating tray 3 in this example is
Circular ceramic flat plate (support plate) 4 on which the wafer 2 is placed
And a metal clip 5 having a U-shaped cross section for fixing the wafer 2. The upper surface of the ceramic flat plate 4 on which the wafer 2 is placed does not need to be processed, and four linear grooves 6 are formed on the outer periphery of the ceramic flat plate 4 at intervals of 90 degrees in the circumferential direction.

Further, four metal clips 5 are provided corresponding to the four grooves 6 of the ceramic flat plate 4, and a straight line fitted into the grooves 6 is provided at an intermediate portion of an upper piece of each clip 5. Shaped protrusions 7 are provided. Further, two of the four metal clips 5 are provided with a handle portion 8 having an L-shaped cross section on the upper surface thereof.

FIG. 3 is a sectional view of the peripheral portion of the tray 5 to which the metal clip 5 is attached.

A step 9 is formed below the peripheral edge of the tray 3. This step 9 is for inserting and removing a fork or the like to support the tray 3, and to mount or take out the tray 3 on the heater by this fork.

The protrusion 7 is provided on the upper piece 5a of the metal clip 5.
Is bent and integrally formed. The upper piece 5a has a length to reach the wafer edge portion in order to hold the wafer 2 on the tray 3 from its side surface. The lower piece 5b of the clip 5 has a short length corresponding to the width of the step 9.

According to the wafer heating tray having the above structure,
After the wafer 2 is placed on the ceramic flat plate 4, four metal clips 5 are sandwiched by the upper piece 5a and the lower piece 5b of each clip 5 from above and below between the peripheral edge of the wafer 2 and the peripheral edge of the ceramic flat plate 4. The wafer 2 is mounted and fixed on the ceramic flat plate 4 by inserting it from the direction of the arrow as described above.
The wafer heating tray 3 having the wafer 2 mounted and fixed on the ceramic flat plate is put into the curing furnace 1 of FIG.

Since the wafer mounting portion of the tray 3 is made of a ceramic material, as described above, there is almost no thermal expansion and contraction, no warpage occurs due to heating and cooling, and flatness is maintained and secured. it can. Therefore, wafer 2
Since the heat distribution during heating is uniform, a high quality wafer 2 can be obtained.

The ceramic flat plate 4 on which the wafer 2 on the tray 3 is placed is originally flat on both sides, and the wafer 2 is fixed to the ceramic flat plate 4 by the metal clip 5. No processing is required to fix it.

Further, since the processing for fixing the wafer 2 to the ceramic flat plate 4 is not required, the outer shape of the wafer heating tray 3 can be set to a desired arbitrary shape.

Further, in this example, when the wafer 2 is placed and fixed on the ceramic flat plate 4, the projection 7 of the metal clip 5 is fitted into the groove 6 of the ceramic flat plate 4, so that the displacement of the metal clip 5 is surely performed. Therefore, the wafer 2 can be mounted and fixed more reliably. in this case,
Although it is necessary to form a groove in the ceramic flat plate 4, this processing is extremely simple, so that the processing cost can be kept extremely low as compared with the conventional example shown in FIG.

In the above embodiment, the case where the wafer heating tray according to the present invention is placed in the curing furnace has been described, but the present invention is not limited to this, and the present invention is applied to other heating furnaces such as an oxidation furnace and a diffusion furnace. Of course good. Further, the wafer supporting plate is not limited to the ceramic plate and may be a quartz flat plate.

[0026]

As described above, according to the present invention,
The wafer is placed by using a standard shape ceramic or flat plate without processing, and the wafer is fixed with a metal clip that is a separate body from this flat plate. Compared with, the flatness can be maintained and ensured without deformation of the mounting surface of the wafer.
Therefore, the heat distribution can be made uniform when the wafer is heated, and a high quality wafer can be obtained. Also,
Compared to a conventional tray in which a concave portion for mounting and fixing a wafer is processed on a ceramic flat plate, it is possible to save troublesome processing and reduce the cost by not processing, and the external shape can be changed to a desired arbitrary shape. can do.

Further, by providing a groove on the ceramic flat plate and providing a projection for fitting into the groove on the metal clip,
The shift of the metal clip can be prevented, and the wafer can be more securely clamped and fixed. Even in this case, since the groove provided on the ceramic flat plate is easy to process, the processing cost can be reduced as compared with the conventional tray in which the recess for fixing the wafer is fixed on the ceramic flat plate.

[Brief description of drawings]

FIG. 1 is a schematic view of a curing furnace containing a wafer heating tray according to the present invention.

FIG. 2 is an external perspective view showing an example of implementation of the wafer heating tray according to the present invention.

FIG. 3 is a cross-sectional view of the peripheral portion of the tray with a metal clip attached.

FIG. 4 is an external perspective view showing a conventional wafer heating tray.

FIG. 5 is an external perspective view showing another conventional wafer heating tray.

[Explanation of symbols]

1: Cure furnace, 2: Wafer, 3: Wafer heating tray,
4: Ceramic flat plate (support plate), 5: Metal clip,
6: groove, 7: protrusion, 8: handle part.

Claims (3)

[Claims] 1. A wafer heating tray on which a wafer is placed and fixed and placed in a heating furnace, wherein the wafer heating tray includes a support plate having a flat upper surface on which the wafer is placed, the support plate being made of ceramic or quartz. A wafer heating tray comprising a metal clip for fixing the wafer on a plate. 2. The metal clip is composed of a clip having a U-shaped cross section for holding and fixing the wafer, a groove is provided on an outer periphery of a wafer mounting portion of the support plate, and a protrusion is provided on one piece of the clip. 2. The wafer heating tray according to claim 1, wherein the clip is locked by fitting a groove into the groove. 3. The wafer heating tray according to claim 2, wherein in the metal clip, an upper piece forming the U-shape is longer than a lower piece.