JP2547187Y2 - PCB holder - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate holder for holding a substrate for crystal growth in a liquid phase epitaxial growth method, and more particularly to a substrate holder for easily removing a substrate from the holder after epitaxial growth. It is about improvement.

[0002]

2. Description of the Related Art In recent years, techniques for utilizing infrared rays have been rapidly advancing.

As a material for the infrared detecting element, mercury / cadmium / tellurium (H) having a narrow energy band gap is used.
A ternary compound semiconductor crystal made of g _1-x Cd _x Te) has received the most attention because of its high sensitivity and high speed. An image sensor for obtaining infrared rays emitted from an object as an image is made by arranging a large number of minute infrared detecting elements (pixels) two-dimensionally on a plane by photolithography. Since these pixels need to have the same characteristics with respect to infrared rays, conventionally, the above ternary compound semiconductor crystal having uniform characteristics, a large area, and a smooth crystal surface has been manufactured for these pixels. In addition, it is required to be divided into small portions.

As a method for obtaining such a large-area compound semiconductor crystal thin film, a liquid phase epitaxial growth method is generally used. This is because the apparatus required for this method is relatively simple, and the composition of the obtained crystal thin film can be easily controlled. However, while having such advantages, for example, there is a difficulty in uniformity of the thickness and composition of the obtained crystal thin film in the film, and a portion that can be used to obtain an element having uniform characteristics. It is pointed out that there is a problem in increasing the production efficiency due to the limited production.

Under such technical background, an improved dipping method which has solved the above-mentioned drawbacks has recently been proposed.

That is, in this method, as shown in FIG. 6A, a substrate b and a compound semiconductor crystal material c are sealed in an ampoule a, and the ampoule a is heated in an electric furnace (not shown) and the compound semiconductor is heated. After the crystal material c is melted to obtain a raw material melt c ′, the ampule a is rotated 180 degrees together with the electric furnace so that the ampule a is turned upside down as shown in FIG. And the surface is brought into contact with the raw material melt c ′. Then, after the raw material melt c ′ is subjected to liquid phase epitaxial growth, the ampoule a is turned upside down again to separate the raw material melt c ′ from the substrate b.

In this method, as a conventional substrate holder d for holding the substrate b, as shown in FIG. 7, a columnar main body d1 made of a quartz plate or the like and a substantially upper center of the main body d1 are provided. And a recess d2 having the same depth as the thickness of a substrate to be applied (not shown) and having a slightly larger area than the above-mentioned substrate.
The board was fitted and held in d2.

In the substrate holder d, the surface of the substrate and the upper surface of the main body d1 are appropriately adjusted so as to form the same plane, and a device is devised so as not to affect the movement of the raw material melt. .

[0009]

In the improved dipping method, the ampoule is rotated to make the surface of the substrate upward and horizontal as described above, and the surface is brought into contact with the raw material melt for epitaxial growth. However, at this time, as shown in FIG.
When there is a gap e between the concave portion d2 and the substrate b, the raw material melt c 'enters the gap e and solidifies on the side and bottom sides of the substrate b.

As a result, since the substrate b is fixed to the substrate holder d via the solidified raw material, it may be difficult to remove the substrate b from the substrate holder d after epitaxial growth. .

Since the solidified raw material cannot be removed from the back side of the substrate holder d, the solidified raw material existing in the gap e between the substrate b and the substrate holder e can be removed from the upper surface side of the substrate holder d. And the substrate b must be taken out by engraving, and there is a problem that the crystal formed at the time of taking out is easily damaged.

In this case, the recess in the substrate holder d
A method of improving the processing accuracy of d2 may be considered, but it is practically difficult to eliminate the gap e because the processing of the bottom surface and the inner wall surface of the concave portion d2 involves difficulty.

As the area of the substrate b increases, the processing accuracy of the substrate holder d decreases, and the matching between the substrate b and the concave portion d2 of the substrate holder d deteriorates. The present invention, which had the problem of becoming a problem, was made by paying attention to such a problem, and the problem is to improve the consistency with the substrate and to make the substrate after epitaxial growth. An object of the present invention is to provide a substrate holder which can be easily removed.

[0014]

That is, the invention according to claim 1 is arranged at an upper side in a sealed tube, holds a substrate in a concave portion thereof, and seals when the sealed tube is turned upside down. Assuming a substrate holder for contacting the raw material melt disposed on the lower side in the tube with the substrate and performing liquid phase epitaxial growth, and having an opening slightly larger than the substrate at substantially the center thereof, the thickness of which is the thickness of the substrate A holder body having a larger holder part and a convex part which is slidably fitted into an opening of the holder part and forms a concave part for holding the substrate. It is.

In the substrate holder according to the present invention, a recess is formed by the opening of the holder component and the projection of the holder body slidably fitted in the opening, and the substrate is formed in the recess. And hold it.

In this case, since the inner wall surface of the opening and the upper surface of the convex portion are relatively easy to process as compared with the conventional method in which the concave portion of the substrate holder is directly processed, the processing accuracy is higher than before, and Can be improved.

In order to remove the substrate from the substrate holder after the epitaxial growth, first, the holder body is pulled out from the holder component in a direction opposite to the surface on which the crystal is formed to expose the substrate. Let it. At this time, the consistency between the substrate and the concave portion is improved, and the amount of solidified crystal raw material existing between the bottom surface side of the substrate and the upper surface of the convex portion of the holder main body is smaller than in the related art. Never. Next, the exposed substrate is extruded from the back side to the crystal forming surface side, and the substrate is taken out from the opening of the holder component and separated. At this time, the amount of solidified crystal material existing between the side surface of the substrate and the inner wall of the opening is smaller than in the related art, so that the operation of taking out the substrate is not hindered as described above.

As described above, the substrate can be easily removed from the substrate holder without touching the formed crystal, and the crystal damage at the time of removal can be minimized. It has the advantage of increased efficiency.

Next, the invention according to a second aspect is based on the substrate holder according to the first aspect, wherein the holder main body has a protruding base portion protruding outward from a side surface of the convex portion at a base end side thereof,
A gap is formed between the holder component and the protruding base when fitted with the holder component.

In the substrate holder according to the second aspect, by moving the holder component in the direction in which the gap is narrowed, the convex portion of the holder main body relatively rises and the substrate mounted on the convex portion surface. Can be protruded from the opening of the holder component, so that there is an advantage that the substrate can be more easily removed from the substrate holder.

In the substrate holder according to the second aspect, when the holder component is rapidly moved in a direction in which the gap is narrowed, an excessive load is applied to the formed crystal if the force is not properly applied. There is a risk of damaging the leverage crystal.

According to a third aspect of the present invention, there is provided a substrate holder according to the second aspect, wherein an elastic member such as a spring is provided in a gap formed between the projecting base of the holder body and the holder component. Is interposed.

That is, by interposing the elastic member, the elastic member absorbs a part of the force applied to the holder component and reduces the load on the crystal, thereby minimizing crystal damage. Becomes possible.

The invention according to claim 4 is based on claims 1-3.
The holder component and the holder body are made of any of quartz, carbon, and ceramic.

In such technical means, the shape of the concave portion for holding the substrate is arbitrary according to the shape of the substrate, and includes, for example, a rectangular shape, a circular shape, and an elliptical shape. Further, it is desirable that the depth of the concave portion is set to be the same as the thickness of the substrate as in the related art, and is adjusted so that the substrate surface and the upper surface of the holder component form the same surface.

The substrate held by the substrate holder according to the present invention is appropriately selected depending on the kind of semiconductor crystal required by the liquid phase epitaxial growth method. For example, mercury / cadmium / tellurium (Hg) described in the prior art is used. _In the case of a ternary compound semiconductor crystal composed of _1-x Cd _x Te), a cadmium tellurium or a compound semiconductor crystal substrate in which at least one of zinc, manganese, and selenium is added to cadmium tellurium is mentioned.

In these technical means, the thickness of the crystal can be easily controlled by changing the material of the holder body and the holder parts to those having an appropriate thermal conductivity.

[0028]

According to the present invention, a substrate holder for holding a substrate is provided with an opening slightly larger than the substrate at substantially the center thereof, and a holder component whose thickness is larger than the thickness of the substrate. A holder main body having a convex portion which is slidably fitted into the opening of the holder component and forms a concave portion for holding the substrate.

Since the processing of the inner wall surface of the opening and the upper surface of the convex portion is easier than the conventional method of directly processing the concave portion, the processing accuracy is improved, and the concave portion formed by the opening portion and the convex portion is improved. Of the substrate and the substrate can be improved.

Further, after the epitaxial growth, the holder body is pulled out from the holder component in a direction opposite to the surface on which the crystal is formed to expose the substrate, and the substrate is formed from the rear side. By pushing it to the surface side, it can be easily removed from the opening of the holder component.

Alternatively, one of the holder main body and the holder component is moved to relatively raise the convex portion of the holder main body, and the substrate mounted on the convex portion surface is protruded from the opening of the holder component. Can also be easily removed.

Accordingly, since the substrate can be easily removed from the substrate holder without touching the formed crystal, damage to the crystal when removing the substrate can be minimized.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings.

That is, the main part of the substrate holder 1 according to this embodiment is composed of the holder main body 2 and the holder component 3 as shown in FIG.

First, as shown in FIG. 2A, the holder main body 2 has a thickness of 2 mm corresponding to a substrate size of 30 × 30 mm.
, And a disc-shaped protruding base 22 having an external shape of 48 mm protruding outward from the side face of the protruding portion 21. Both the protruding portion 21 and the protruding base 22 are made of quartz material. Is formed.

On the other hand, the holder part 3 is made of a quartz material having the same shape as the protruding base 22 of the holder body 2 and corresponds to the projection 21 of the holder body 2 as shown in FIG. Opening 3 of the shape corresponding to this
1 is provided. The thickness of the holder part 3 is set to 3.5 mm, and as shown in FIG. 1, the concave part 10 formed when the convex part 21 of the holder main body 2 and the opening 31 are fitted. Is made to match the thickness of the substrate.

Then, as shown in FIG.
The substrate 4 is fitted into and held by the concave portion 10 formed by fitting the convex portion 21 of the holder component 3 and the opening portion 31 of the holder component 3.

At this time, the upper surface of the projection 21 and the opening 31
Since the processing of the inner wall surface and the like is easier than the conventional method in which the concave portion is directly processed, the processing accuracy is increased and the concave portion 10 formed by the opening portion 31 and the convex portion 21 and the substrate 4 The consistency is in a good state.

In order to remove the substrate 4 from the substrate holder 1 according to this embodiment after the epitaxial growth, the holder component 3 can be removed from the holder component 3 in the direction opposite to the surface on which crystals (not shown) are formed. The main body 2 is pulled out to expose the bottom surface of the substrate 4, and then the substrate 4 is extruded toward the crystal forming surface side and taken out from the opening 31 of the holder component 3.

At this time, since the matching between the substrate 4 and the concave portion 10 is good, the bottom surface of the substrate 4 and the convex
Since there is almost no solidified crystal raw material between the upper surface or between the side surface of the substrate 4 and the inner wall of the opening 31, the operation of taking out the substrate 4 is not hindered.

As described above, when taking out the substrate 4 from the substrate holder 1, the substrate 4 can be easily taken out without touching the formed crystal, so that damage to the crystal at the time of taking out is minimized. This has the advantage that it becomes possible.

The thickness of the holder component 3 is appropriately set in consideration of the desired depth of the recess 10 and the height of the projection 21, and the like. By setting a large value, the mechanical strength can be increased.

As shown in FIG. 4, the height of the convex portion 21 of the holder body 2 is set large so that the gap 5 between the holder component 3 and the protruding base 22 of the holder body 2 is formed.
May be adopted.

In the case of such a structure, the holder component 3
Is pressed down to relatively raise the protrusion 21 of the holder body 2, the substrate 4 can be more easily taken out.

Further, a structure in which an elastic member 50 such as a spring is interposed in the gap 5 as shown in FIG.

In the case of such a structure, when the holder part 3 is pushed down, the holder part 3
Since a part of the force applied to the crystal can be absorbed by the elastic member 50, it is difficult for a sudden load to be applied to the formed crystal, and the damage thereof can be minimized.

[0047]

According to the invention, since the substrate can be easily removed from the substrate holder without touching the formed crystal, damage to the crystal when the substrate is removed is minimized. It becomes possible.

Accordingly, there is an effect that the production efficiency in the liquid phase epitaxy growth method can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a substrate holder according to an embodiment.

FIG. 2A is a perspective view of a holder body, and FIG. 2B is a perspective view of a holder component.

FIG. 3 is a cross-sectional view of the substrate holder according to the embodiment.

FIG. 4 is a cross-sectional view of a substrate holder according to a modification.

FIG. 5 is a cross-sectional view of a substrate holder according to a modification.

FIGS. 6A and 6B are explanatory views of an improved dipping method in a liquid phase epitaxial growth method.

FIG. 7 is a perspective view of a substrate holder according to a conventional example.

FIG. 8 is an explanatory view showing a use state of a substrate holder according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate holder 2 Holder main body 3 Holder component 4 Substrate 5 Gaps 6 Sealed tube 10 Depression 21 Convex part 22 Protrusion base 31 Opening 50 Elastic member

Claims (4)

(57) [Scope of request for utility model registration] 1. A raw material melt disposed on an upper side of a sealed tube, holding a substrate in a concave portion thereof, and disposed on a lower side of the sealed tube when the sealed tube is turned upside down. In a substrate holder for liquid phase epitaxial growth by contacting with a substrate, a holder part having an opening slightly larger than the substrate at substantially the center thereof and having a thickness larger than the thickness of the substrate, and sliding into the opening of the holder part A holder body provided with a convex portion which is fitted as possible to form a concave portion in which the substrate is held. 2. The holder main body further includes a protruding base protruding outward from a side surface of the protruding portion on a base end side thereof, and is provided between the holder component and the protruding base when fitted to the holder component. 2. The substrate holder according to claim 1, wherein a gap is formed. 3. The substrate holder according to claim 2, wherein an elastic member is interposed in a gap formed between the projecting base of the holder main body and the holder component. 4. The substrate holder according to claim 1, wherein the holder component and the holder body are made of any one of quartz, carbon, and ceramic.