JPH0533014Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a support jig used in a high-temperature atmosphere, and in particular, a support jig that is housed in a high-temperature furnace to manufacture semiconductor devices for the electronic industry. The present invention relates to a support jig used as a support for wafers made of materials such as the following.

(Prior art) Conventionally, this type of support jig used to support a wafer has been made of quartz, carbon, etc.
Silicon carbide composites or composites made of silicon carbide molded bodies filled with metallic silicon are known, but some of these products have poor heat resistance or are very expensive. Therefore, it is not suitable as a practical jig. Therefore,
A structure in which a three-dimensional mesh-like skeleton made of silicon carbide is filled with metallic silicon has also been proposed.

However, no matter which material is used to form this type of support jig, since the support jig is used in a high-temperature atmosphere, its thermal expansion must be fully considered. Furthermore, in the supporting jigs of this kind that have been proposed in the past, sufficient consideration has not been given to this change in shape due to thermal expansion. In particular, in recent years, wafer support jigs have become larger with the aim of mass-producing wafers, and the above-mentioned thermal expansion has become a phenomenon that cannot be ignored.

For example, in recent years, support jigs of this type that are being manufactured have a length of 1000 mm or more. The temperature inside the furnace where this type of support jig is inserted exceeds 1000℃, and even if silicon carbide has a relatively low coefficient of thermal expansion, the coefficient of linear thermal expansion is on the order of the order of magnitude.
Since the temperature is approximately 10 ^-6 /°C, as a result, this support jig as a whole is observed to elongate by several mm.

Generally, the support jig 20 that has been proposed in the past usually has the following structure. That is, as shown in FIG. 5, a plurality of support rods 21 and 22 each having a large number of grooves 23 in which a wafer 30, which is a material for a semiconductor element, is supported is inserted into each groove 23.
By connecting the wafers 30 via the support stand 24 so that the wafers face inward, each wafer 30 is supported by the groove 23. When considering the conventional support jig 20 of this type, especially the groove 23 formed in the lower support bar 22, it is found that the width of the groove 23 is usually approximately the same as the width of the wafer 30. Moreover, the side portions thereof are formed substantially parallel.
Further, each groove 23 of the upper support bar 21 is also formed to have approximately the same width as the groove 23 on the lower support bar 22 side.

If the support jig 20 has such a structure, when a difference in thermal expansion occurs between the upper support rod 21 and the lower support rod 22, the difference between the upper support rod 21 and the lower support rod 22 The positions of the respective grooves 23 are shifted relative to each other, and the wafer 30 supported within these grooves 23 is, so to speak, forced due to the positional shift of the support portions. In this case, the wafer 30 is bent, and in some cases, the wafer 30 is thin and may be damaged. In particular, the longer the length of the support jig itself, the more clearly this phenomenon appears. This is presumably because each of the grooves 23 is formed by surfaces parallel to each other, and each wafer 30 is supported by these surfaces.

A case where a difference in thermal expansion occurs between the upper support bar and the lower support bar means that when the heated support jig is taken out of the furnace, it is placed on a desk etc. via the support stand. This is the case when the lower support bar is cooled faster than the upper support bar. In addition, when storing the support jig in the furnace, the jig for loading and unloading is placed in contact with the lower support bar, but the heat capacity of the lower part of the support jig is higher than that of the upper part, causing the temperature to rise. This also causes a difference in thermal expansion between the upper and lower support bars.

Moreover, as described above, when the width of each groove 23 is increased, the support jig 4 supporting each wafer 30
When the wafer 30 is being transported, the wafer 30 may shake inside each groove 23, which may cause damage to the wafer 30.

If the grooves 23 formed in the upper support rod 21 and the lower support rod 22 have the shapes shown in FIG. 5, they will have an adverse effect on the wafer 30 as described above, but this problem can be solved. Therefore, it is conceivable to increase the size of each groove 23 as shown in FIG. However, in this way, each groove 2
If the width of 3 is made larger, one support jig 40
Not only is it impossible to support a large number of wafers 30, but also the wafers 30 are fired in contact with each other, making it impossible to obtain high-quality wafers 30.

(Problem to be solved by the invention) The invention was made in view of the above-mentioned circumstances, and the problem to be solved is the difference in thermal expansion between the upper and lower parts of the support jig. , and the adverse effects on the wafer due to rattling when the groove becomes too large.

The purpose of this invention is to be able to support the wafer without being adversely affected by this difference and without wobbling, even if there is a difference between the upper and lower parts of the support jig due to thermal expansion. An object of the present invention is to provide a support jig with a simple structure.

(Means for Solving the Problems) In order to solve the above problems, the means adopted by the present invention are explained with reference to FIGS. 1 to 4 corresponding to the embodiments. A wafer support jig comprising a plurality of support rods each having a large number of grooves for supporting a wafer 30, which is a material of The bottom surface 13a of each groove 13 of the support bar 12 located on the lower side has a width approximately equal to the width of the end surface of the wafer 30, and the side surface 13c of each groove 13 has an opening larger than this bottom surface 13a. In addition, the width of the side surface portion 13b of each groove 13 of the support bar 11 located on the upper side expands in the insertion direction of the wafer 30 or the opposite direction, whichever is at least one side. , a support jig 10 for a wafer 30, which is formed with a support portion that makes point or line contact with the surface of the wafer 30 inserted into the groove 13 at its minimum width portion.

That is, in this support jig 10, the bottom surface portion 13a of each groove 13 of the lower support bar 12 is connected to the wafer 30.
The side surface portion 13c of each groove 13 is configured to have a larger opening than the bottom surface portion 13a, and the upper support bar 11
The width of the side surface portion 13b of each groove 13 of the wafer 3 is
By forming a support part that extends in at least one side of either the insertion direction of 0 or the opposite direction, and makes point or line contact with the surface of the wafer 30 inserted into the groove 13 at its minimum width, Recessed grooves 1 are formed between the upper support bar 11 and the lower support bar 12 due to a difference in thermal expansion between them.
Even if the relative positions of the wafers 3 and 3 are shifted, the expansion of the width of the side surface portion 13b absorbs the change in the positional shift of each groove 13, and the support portion that contacts the surface of the wafer 30 at a point or line It is designed to ensure support for the

(Aspects of operation and use of the invention) Since the support jig 10 according to the invention has the above configuration, it has the following effects. That is, in a normal state, in other words, when there is no difference due to thermal expansion between the upper support bar 11 and the lower support bar 12, and there is no change in positional deviation, each The concave groove 13 is connected to each wafer 30.
is supported in a vertical position. Further, in this case, each wafer 30 has a groove 13 inside each groove 13 of the upper support bar 11 that supports the upper part of the wafer 30.
The support portion of the side surface portion 13b makes contact at a point or a line. This is the upper support bar 1
This is because each groove 13 of No. 1 is enlarged in at least one direction, either in the insertion direction of the wafer 30 or in the opposite direction. Therefore, each wafer 30 does not wobble within the groove 13 in which it is supported.

In this way, the groove 13 supporting each wafer 30 is connected to the upper support bar 11 and the lower support bar 1.
Even if the relative positions of the wafers 30 shift due to thermal expansion changes occurring between the wafers 30 and 2, in the examples shown in FIGS. Becomes slanted. In this case, in particular, each groove 13 of the lower support bar 12 is
Since it is composed of a bottom surface portion 13a having a width approximately equal to the width of the end surface of the wafer 30, and a side surface portion 13c having a shape wider than this bottom surface portion 13a,
The lower end of the wafer 30 is connected to the bottom surface 1 of each groove 13.
3a, it is supported with the angle slightly changed, but the support position remains unchanged.

On the other hand, even if each wafer 30 is in an inclined state,
In the upper support bar 11, the width of the side surface 13b of each of the grooves 13 expands in at least one direction, either in the insertion direction of the wafer 30 or in the opposite direction, and the minimum width portion thereof extends into the groove. Each groove 13 forms a support portion that contacts the surface of the inserted wafer at a point or a line, so that each groove 13
The wafer 30 is reliably supported by the support while avoiding any positional changes. Further, in the case of the example shown in FIG. 4, although the contact portion of each wafer 30 with the groove 13 changes, each groove 13 misses the change in the position of the wafer 30, and the wafer 30
There is no change in supporting 0.

Therefore, in the support jig 10 according to the present invention, even if the relative positions of the upper support rod 11 and the lower support rod 12 are shifted due to thermal expansion changes, each groove 13 is aligned with the wafer 30. In other words, unnecessary force is applied to the wafer 30 without adversely affecting the wafer 30.
It supports it without adding to it.

(Example) The present invention will be described in detail below according to an example shown in the drawings.

FIG. 1 shows an overall perspective view of a support jig 10 according to the present invention.
A plurality of support bars 11 and 12 each having a large number of
Each wafer 30 is supported by the grooves by connecting them via the support base 14 so that the grooves 13 face inward. In this embodiment, the upper support rod 11, the lower support rod 12, and the support stand 14 are made of silicon carbide, and are formed by filling a three-dimensional mesh skeleton with metal silicon. The support jig 10 is designed to have excellent heat resistance.

In the case of the upper support bar 11, the width of the side surface portion 13b of each groove 13 formed therein is determined by the width of the wafer 30.
It is formed so as to be enlarged in at least one side of the insertion direction or the opposite direction. That is, in the support jig 10 shown in FIG. 2, the width of the side surface portion 13b of each groove 13 is expanded upward, and in the support jig 10 shown in FIG. In the case, the side surface 1 of each groove 13
3b width expanded downward. In addition, in the case of the support jig 10 shown in FIG. 4, the width of the side surface portion 13b of each groove 13 is formed into an arc shape that expands outward, thereby expanding both upward and downward. This is what I did.

That is, as shown in FIG.
The width of the side surface portion 13b is increased in any direction perpendicular to the length direction of the upper support bar 11. As a result, when inserting the wafer 30 into the groove 13, the operation can be performed from the wider side of the groove 13 without any difficulty, and the wafer 30 can be supported on the narrower side of the groove 13. is done without any wobbling.

On the other hand, as shown in FIG. 2 to FIG.
a, and a side surface portion 13c forming an opening larger than the bottom surface portion 13a. Bottom part 1
The reason why the width of the wafer 3a is approximately the width of the end surface of the wafer 30 is to allow the end of the wafer 30 to abut against the bottom surface portion 13a without being displaced.

(Effect of the invention) As explained above, the support jig 1 according to the invention
0, as exemplified in the above embodiment, "each concave groove 13 of the lower support bar 12 is connected to the wafer 3".
a bottom surface portion 13a having a width approximately equal to the width of the end surface of 0;
and a side surface portion 13c forming an opening larger than this bottom surface portion 13a, and a side surface portion 13b of each groove 13 of the upper support bar 11.
The width of the supporting portion expands in the insertion direction of the wafer 30 or the opposite direction thereof, and forms a supporting portion that contacts the surface of the wafer 30 inserted into the groove 13 at a point or a line at its minimum width portion. The support jig is characterized by the fact that, even if there is a difference between the upper and lower sides of the support jig due to thermal expansion, the support jig can support the wafer 30 without being adversely affected by this difference. 10 can be provided with a simple configuration.

That is, in the support jig 10 according to the present invention, the width of the side surface portion 13b of each groove 13 of the upper support bar 11 is expanded in at least one of the insertion direction of the wafer 30 and the opposite direction. Therefore, each groove 13 can support the wafer 30 while avoiding changes in the position of the wafer 30. In addition, in this support jig 10, each groove 13 of the lower support bar 12 is formed in a bottom surface portion 13a having a width approximately equal to the width of the end surface of the wafer 30.
and a side surface portion 13c forming a larger opening than the bottom surface portion 13a, the wafer 3
0 can be supported by the bottom surface 13a of each groove 13 with the angle slightly changed, and the support position can be supported without changing this. Therefore, the support jig 10 can support each wafer 30 without adversely affecting each wafer 30 even if a relative positional shift occurs between each upper support rod 11 and lower support rod 12 due to thermal expansion. It is.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the support jig according to the present invention;
The figure is a partially enlarged vertical cross-sectional view taken along - in Fig. 1, Figs. 3 and 4 are partially enlarged longitudinal cross-sectional views corresponding to Fig. 2 showing other embodiments of the present invention, and Fig. 5. 6 is a partial enlarged vertical sectional view corresponding to FIG. 2 showing a conventional support jig, and FIG. 7 shows the state of the grooves formed in each support bar of the support jig shown in FIG. FIG. 3 is a schematic partially enlarged plan view. Explanation of symbols, 10... Support jig, 11... Upper support bar, 12... Lower support bar, 13... Concave groove, 13a... Bottom part, 13b, 13c... Side part, 14... Support stand, 20, 40... (conventional)
Support jig, 30...wafer.

Claims (1)

[Claims for Utility Model Registration] A plurality of support rods each having a large number of grooves for supporting a wafer that is a material for a semiconductor device are connected via a support base so that each of the grooves faces inward. A wafer support jig consisting of a wafer support jig, wherein a bottom surface portion of each groove of the support bar located on the lower side has a width approximately equal to the width of an end surface of the wafer, and a side surface portion of each groove has a width approximately equal to the width of an end surface of the wafer. The opening is configured to be larger than the bottom surface portion, and the width of the side surface portion of each concave groove of the support bar located on the upper side is at least equal to the width of the wafer insertion direction or the opposite direction thereof. A wafer support jig, characterized in that it is formed with a support part that extends to one side and makes point or line contact with the surface of the wafer inserted into the groove at its minimum width part.