JPH0566073U - Board holder - Google Patents

Abstract

(57) [Summary] [Objective] To provide a substrate holder for easily removing a substrate for crystal growth after liquid phase epitaxial growth. [Structure] This substrate holder 1 is provided with an opening 31 slightly larger than the substrate at substantially the center thereof, and a holder component 3 having a thickness larger than that of the substrate, and slidably fitted in the opening 31 of the holder component 3. A main part of the holder main body 2 is provided with a convex portion 21 that is joined to form the concave portion 10 for holding the substrate. Then, in order to remove the substrate from the substrate holder 1, the holder body 2 is pulled out from the holder part 3 in the direction opposite to the crystal forming surface to expose the bottom surface of the substrate, and the substrate is extruded to the crystal forming surface side. It is to be removed from the opening 31. At this time, since the substrate is taken out without touching the formed crystal, it is possible to minimize crystal damage.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 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 an improvement of a substrate holder for easily removing the substrate from the holder after epitaxial growth.

[0002]

[Prior Art]

 In recent years, infrared technology has rapidly advanced.

A ternary compound semiconductor crystal made of mercury, cadmium, tellurium (Hg _1-x Cd _x Te), which has a narrow energy band gap, has attracted the most attention as a material for the infrared detection element because of its high sensitivity and high speed. .. An image sensor for obtaining infrared rays emitted by 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 it is necessary for these pixels to have the same characteristics for all infrared rays, conventionally, for this pixel, the ternary compound semiconductor crystal with uniform characteristics, large area, and smooth crystal surface was used. It is required to manufacture and divide it into small pieces.

By the way, as a method for obtaining such a large area compound semiconductor crystal thin film, a liquid phase epitaxial growth method is generally used. The reason is that the apparatus required for this method is relatively simple and the composition of the obtained crystal thin film can be easily controlled. However, on the other hand, although it has such advantages, for example, there is a problem in the uniformity of the thickness and the composition of the obtained crystal thin film within the film, and therefore it can be used to obtain an element with uniform characteristics. It is also pointed out that there is a hindrance to improving the production efficiency because the production capacity is limited.

Under such a technical background, recently, an improved depping method that solves the above drawbacks has been proposed.

That is, according to this method, a substrate b and a compound semiconductor crystal material c are enclosed in an ampoule a as shown in FIG. 6 (A), and the ampoule a is heated in an electric furnace (not shown) to produce a compound semiconductor. After the crystalline material c is melted to obtain the raw material melt c ′, the ampoule a is rotated 180 degrees together with the electric furnace to turn the ampoule a upside down as shown in FIG. 6 (B), and the surface of the substrate b. Is made horizontal and the raw material melt c ′ is brought into contact with the surface. Then, after the raw material melt c'is subjected to liquid phase epitaxial growth, the upper and lower sides of the ampoule a are inverted again to separate the raw material melt c'and the substrate b.

As a conventional substrate holder d for holding the substrate b in this method, as shown in FIG. 7, a cylindrical main body d1 made of a quartz plate or the like and an upper surface of the main body d1 provided substantially at the center thereof are provided. The main part is composed of a recess d2 having the same depth as the thickness of the applicable substrate (not shown) and having a slightly larger area than the above-mentioned substrate, and the substrate is fitted into this recess d2. It was something to hold.

The substrate holder d is appropriately adjusted so that the substrate surface and the upper surface of the main body d1 form the same plane, and is devised so as not to affect the movement of the raw material melt. It was

[0009]

[Problems to be solved by the device]

 By the way, in this improved dipping method, as described above, the ampoule is rotated to make the substrate surface upward and horizontal, and then the surface and the raw material melt are brought into contact with each other for epitaxial growth. As shown in FIG. 8, if there is a gap e between the recess d2 of the substrate holder d and the substrate b, the raw material melt c ′ enters these gaps e and solidifies on the side surface or bottom surface side of the substrate b. Will be done.

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 the epitaxial growth. It was

Since the solidified raw material cannot be removed from the rear surface side of the substrate holder d, the solidified raw material existing in the gap e between the substrate b and the substrate holder e from the upper surface side of the substrate holder d. There was a problem that the substrate b had to be carved out and the substrate b had to be taken out, and the crystals formed at the time of taking out were likely to be damaged.

In this case, a method of improving the accuracy by processing the concave portion d2 of the substrate holder d may be considered, but it is difficult to process the bottom surface and the inner wall surface of the concave portion d2, and thus the gap e It was actually difficult to get rid of.

Further, 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 recess d2 of the substrate holder d deteriorates. The present invention has been made by paying attention to such a problem, and the problem is that the above-mentioned substrate can be formed after the epitaxial growth is performed while improving the compatibility with the substrate. It is to provide a substrate holder that can be easily removed.

[0014]

[Means for Solving the Problems]

 That is, the invention according to claim 1 is a raw material which is arranged on the upper side in the sealed tube, holds the substrate in the recess, and is arranged on the lower side in the sealed tube when the sealed tube is turned upside down. Assuming a substrate holder for performing liquid phase epitaxial growth by bringing the melt into contact with the substrate, a holder part having a slightly larger opening than the substrate in the substantial center thereof, and a holder part having a thickness larger than the thickness of the substrate, and this holder And a holder main body having a convex portion that is slidably fitted in the opening of the component to form a concave portion for holding the substrate.

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 placed in the recess. Is inserted and held.

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 recess of the substrate holder is directly processed, the processing accuracy becomes higher than that of the conventional method. It is possible to improve the matching with the recess.

Further, 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 crystals are formed, and the substrate is removed. Expose. At this time, the alignment between the substrate and the concave portion is improved, and the solidified crystal raw material existing between the bottom surface side of the substrate and the upper surface of the convex portion of the holder body is smaller than in the conventional case, so that the pulling operation of the holder body is hindered. It will not be done. Next, the exposed substrate is extruded from the back surface side to the crystal formation surface side, and the substrate is taken out from the opening of the holder component and separated. At this time, since 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 conventional case, the operation of taking out the substrate is not hindered as in the above.

In this way, the substrate can be easily removed from the substrate holder without touching the formed crystal, and damage to the crystal at the time of removal can be minimized. It has the advantage of increased efficiency.

Next, the invention according to claim 2 is premised on the substrate holder according to claim 1, wherein the holder main body is provided with a projecting base portion projecting outward from the side surface of the convex portion on the base end side thereof, It is characterized in that a gap is formed between the holder component and the projecting 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 is placed on the convex surface. Since the substrate can be projected from the opening of the holder component, there is an advantage that the substrate can be taken out from the substrate holder more easily.

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, if the force is not applied well, the formed crystal is overloaded. It may damage the lever crystal.

The invention according to claim 3 prevents this, and is based on the substrate holder according to claim 2, wherein an elastic member such as a spring is provided in a gap formed between the protruding base portion of the holder body and the holder component. Is intervening.

That is, by interposing the elastic member, the elastic member absorbs part of the force applied to the holder component and reduces the load on the crystal, so that damage to the crystal is minimized. It becomes possible.

The invention according to claim 4 is premised on the substrate holder according to claims 1 to 3, wherein the holder component and the holder body are made of any one of quartz, carbon and ceramic materials. It is characterized by that.

The shape of the recess for holding the substrate in such technical means is arbitrary according to the shape of the substrate, and may be, for example, a rectangular shape, a circular shape, an elliptical shape, or the like. Further, it is desirable that the depth of the recess is set to be the same as the thickness of the substrate as in the conventional case, and that the surface of the substrate and the upper surface of the holder component are flush with each other.

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

Further, in these technical means, it is possible to easily control the film thickness of the crystal by changing the material of the holder body or the holder component to one having an appropriate thermal conductivity.

[0028]

[Action]

 According to the inventions according to claims 1 to 4, a substrate holder for holding a substrate is provided with an opening portion slightly larger than the substrate at substantially the center thereof, and a holder component having a thickness larger than that of the substrate, and this holder. The holder body is provided with a convex portion that is slidably fitted in the opening of the 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 increased and the concave portion composed of the opening portion and the convex portion is formed. It is possible to improve the matching between the substrate and the substrate.

After the epitaxial growth, the holder body is pulled out in the direction opposite to the surface on which the crystal is formed from the holder component to expose the substrate, and the substrate is crystallized from the rear side. It can be easily removed from the opening of the holder part by pushing it to the surface side.

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 placed on the convex portion surface is projected from the opening of the holder component. By doing so, it is possible to easily remove it.

Therefore, since the substrate can be easily removed from the substrate holder without touching the formed crystal, it is possible to minimize damage to the crystal when the substrate is removed.

[0033]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

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

First, as shown in FIG. 2A, the holder main body 2 has a protrusion 21 having a thickness of 2 mm corresponding to a substrate size of 30 × 30 mm, and an outer shape 4 protruding outward from the side surface of the protrusion 21. It is composed of a disk-shaped protruding base portion 22 having a diameter of 8 mm, and both the protruding portion 21 and the protruding base portion 22 are made of a quartz material.

On the other hand, the holder component 3 is made of an English material having the same shape as the protruding base portion 22 of the holder body 2, and is provided on the convex portion 21 of the holder body 2 as shown in FIG. 2B. An opening 31 having a shape corresponding to this is provided at a corresponding position. The thickness of this holder component 3 is set to 3.5 mm, and it is formed when the protrusion 21 and the opening 31 of the holder body 2 are fitted to each other as shown in FIG. The depth of the recess 10 is made to match the thickness of the substrate.

Then, as shown in FIG. 3, the substrate 4 is fitted in the concave portion 10 formed by fitting the convex portion 21 of the holder main body 2 and the opening portion 31 of the holder component 3 to hold it. is there.

At this time, the processing of the upper surface of the convex portion 21 and the inner wall surface of the opening 31 is easier than the conventional method in which the concave portion is directly processed. Consistency between the concave portion 10 constituted by the convex portion 31 and the convex portion 21 and the substrate 4 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 is moved 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 to the crystal formation surface side and taken out from the opening 31 of the holder component 3.

At this time, since the alignment between the substrate 4 and the recess 10 is in a good state, there is a gap between the bottom of the substrate 4 and the top of the protrusion 21 or between the side of the substrate 4 and the inner wall of the opening 31. Since there is almost no solidified crystal raw material, the operation of taking out the substrate 4 is not hindered.

As described above, when the substrate 4 is taken out from the substrate holder 1, the substrate 4 can be easily taken out without touching the formed crystal, and therefore the crystal damage at the time of taking out can be minimized. Has the advantage that

The thickness dimension of the holder component 3 is appropriately set in consideration of the depth dimension of the intended concave portion 10 and the height dimension of the convex portion 21. It is possible to increase the mechanical strength by setting a large value.

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

In the case of such a structure, the substrate 4 can be taken out more easily by pushing down the holder part 3 to relatively raise the convex portion 21 of the holder body 2.

Further, as shown in FIG. 5, an elastic member 50 such as a spring may be interposed in the gap 5 as described above.

With this structure, a part of the force applied to the holder part 3 when the holder part 3 is pushed down can be absorbed by the elastic member 50. It becomes difficult for a sudden load to be applied to the crystals that are formed, and the damage can be minimized.

[0047]

[Effect of the device]

 According to the inventions according to claims 1 to 4, since the substrate can be easily removed from the substrate holder without touching the formed crystal, it is possible to minimize damage to the crystal when the substrate is removed. Become.

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

[Brief description of drawings]

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

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

FIG. 3 is a sectional view of a substrate holder according to an embodiment.

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

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

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 usage state of a substrate holder according to a conventional example.

[Explanation of symbols]

 1 Substrate holder 2 Holder body 3 Holder parts 4 Substrate 5 Gap 6 Sealed tube 10 Recessed portion 21 Convex portion 22 Projected base portion 31 Opening portion 50 Elastic member

Claims (4)

[Scope of utility model registration request] 1. A raw material melt, which is arranged on the upper side in a sealed tube and holds a substrate in the recess thereof, and which is arranged on the lower side in the sealed tube when the sealed tube is turned upside down. In a substrate holder for performing liquid phase epitaxial growth by contacting with a substrate, a holder part having a slightly larger opening than the above-mentioned substrate at substantially the center thereof and a holder part having a thickness larger than that of the substrate and sliding on the opening part of the holder part A holder main body provided with a convex portion that is fitted so as to form a concave portion for holding the substrate, and a holder for a substrate. 2. The holder main body is provided with a projecting base portion projecting outward from the side surface of the projecting portion on the base end side thereof, and between the holder component and the projecting base portion when fitted to the holder component. 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 protruding base portion of the holder 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 materials.