CN211999986U - Assembly structure for high-purity semiconductor single crystal hot isostatic pressing connection - Google Patents

Abstract

An assembly structure for hot isostatic pressing connection of high-purity semiconductor single crystals belongs to the field of semiconductor material preparation, and particularly relates to an assembly structure for preparing a plurality of small-size single crystals into large-size single crystals in a hot isostatic pressing mode. The structure comprises a sheath and a crystal block unit arranged in the sheath, wherein the sheath consists of a sheath main body and a sheath upper cover, the sheath main body or the sheath upper cover is provided with an air exhaust hole, and the inner surface of the sheath is provided with a sheath protective layer; the crystal block unit comprises a plurality of single crystal blocks, the single crystal blocks are combined through connecting surfaces and fixed through a clamp, and a quartz wrapping layer is arranged on the outer surface of the single crystal block unit. Adopt the device provided by the utility model, can realize connecting the preparation into the large-size single crystal with small-size single crystal piece, in the preparation process, the hot isostatic pressing mode makes each direction atress unanimous between each single crystal piece, needn't consider the problem that dislocation, twin, polycrystallization etc. need notice in traditional single crystal growth process, and equipment is simple, can prepare arbitrary size's single crystal in theory.

Description

Assembly structure for high-purity semiconductor single crystal hot isostatic pressing connection

Technical Field

The utility model belongs to semiconductor material preparation field, concretely relates to prepares into the assembly structure of jumbo size single crystal with polylith small-size single crystal through the hot isostatic pressing mode.

Background

The semiconductor material is widely applied to the fields of application in the fields of integrated circuits, communication systems, photovoltaic power generation and the like, and is in a core link in a semiconductor industry chain. Semiconductor single crystal substrates play a critical role in the production and manufacture of chips. The larger the size of a semiconductor single crystal substrate, the lower the cost of the fabricated device, and the increase in the size of a single crystal is one of the developing directions of the semiconductor industry.

At present, the size of the semiconductor is increased mainly by the enlargement of equipment and the enlargement of a thermal field, but the larger the size is, the more difficult the preparation of the single crystal is. For example, for some compound semiconductors, such as gallium arsenide, indium phosphide, etc., which are prepared under a high pressure atmosphere, the device size is increased, and thus thermal field convection may be very strong, and the difficulty of preparation and the cost of single crystal may be greatly increased. The silicon carbide is mainly prepared by physical vapor deposition, and the growth temperature is high, so that the requirement on large-size equipment is higher, and the symmetry of a crystal thermal field is increased. When a large-size single crystal is prepared by a melt method, the size of a crucible is correspondingly increased, and the temperature of the edge of the crucible is higher and higher in order to establish a temperature gradient, so that the strength of the crucible is reduced, and even the crucible cannot bear high temperature to pollute the melt.

Hot isostatic pressing has been widely used in the fields of powder metallurgy, high pressure sintering of ceramics, shrinkage cavity defects in castings, and the like, and is mainly used for pressing materials at high temperature and high pressure by metal or boron oxide, glass, and other envelopes. The metal sheath atoms in the semiconductor single crystal connection process easily pollute semiconductor materials and bring about changes of electrical characteristics, for example, iron atoms can enable indium phosphide to be converted into semi-insulation. The liquid sheathing method is easy to cause liquid substances to enter the joint interface, so that inclusions are formed, and defects and even breakage of semiconductors are caused in the cooling process.

Disclosure of Invention

The utility model provides a new thought, which prepares a large-size high-purity semiconductor single crystal by a solid state connection mode by adopting a hot isostatic pressing method with a plurality of small-size single crystals.

In order to achieve the above object, the utility model adopts the following technical scheme:

the structure comprises a sheath and a crystal block unit arranged in the sheath, wherein the sheath consists of a sheath main body and a sheath upper cover, the sheath main body or the sheath upper cover is provided with an air exhaust hole, and the inner surfaces of the sheath main body and the sheath upper cover are provided with sheath protective layers.

The crystal block unit comprises a plurality of single crystal blocks, the single crystal blocks are combined through connecting surfaces, the single crystal blocks are fixed through a clamp and/or a filling block according to the condition of the single crystal combination, and a quartz wrapping layer is arranged on the outer surface of the fixed single crystal block combination.

Adopt the device provided by the utility model, after the cutting of fritter single crystal, select the whole nearly or the distribution of physical properties is close and the higher single crystal piece of concatenation face crystal orientation precision, connect the face and handle the back assembly together, heat and pressure treatment in the hot isostatic pressing furnace body, and then realize high accuracy, the high even physical properties's of height interface solid state between the semiconductor single crystal piece and connect to accomplish the preparation of bigger size single crystal.

Has the advantages that: 1. the method can realize that the small-sized single crystal blocks are connected and prepared into the large-sized single crystal, 2, in the preparation process, the hot isostatic pressing mode enables all the single crystal blocks to be stressed uniformly, the problems of dislocation, twin crystal, polycrystallization and the like which need to be noticed in the traditional single crystal growth process do not need to be considered, 3, the equipment is simple, and 4, the single crystal with any size can be prepared theoretically.

Drawings

Figure 1 is an assembly embodiment of a hot isostatic pressed bonded monocrystalline ingot,

figure 2 is another assembly embodiment of a hot isostatic pressed bonded monocrystalline ingot,

figure 3 is a schematic illustration of a crystal splicing assembly,

FIG. 4 is a schematic view of a precision splicing assembly of multiple single crystals.

Wherein: 1: a single crystal block; 2: a fastening collar; 3: covering the bag; 3-1: wrapping an upper cover for sealing edges; 3-2: an air exhaust hole; 4: a fixture; 5; a quartz wrapping layer; 6: a semiconductor powder layer; 7: sheathing a protective layer; 8: sheathing the main body; 8-1: wrapping the edge of the main body; 9; a fastening collar protective layer; 10: a connecting surface; 11: substrate, 12: and filling the blocks.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings.

The structure comprises a sheath and a crystal block unit arranged in the sheath, wherein the sheath consists of a sheath main body 8 and a sheath upper cover 3, an air suction hole 3-2 is formed in the sheath main body 8 or the sheath upper cover 3, and a sheath protective layer 7 is arranged on the inner surfaces of the sheath main body 8 and the sheath upper cover 3.

In the embodiment, the air exhaust hole 3-2 is arranged on the sheath upper cover 3.

The ingot unit comprises a plurality of single crystal blocks 1, the plurality of single crystal blocks 1 are combined through a connecting surface 10, and are fixed by using a clamp 4 and/or a filling block 12 according to the situation of single crystal combination, and are fixed by using the clamp 4. After fixation, the outer surface is provided with a quartz wrapping layer 5.

A fastening collar 2 and a fastening collar protective layer 9 are arranged outside the quartz wrapping layer 5, a boron oxide coating is arranged on the surface of the fastening collar 2, and the thickness of the boron oxide coating is 0.5-1 mm.

The ingot unit is placed in the center of the capsule body 8 and is filled with a powder of a semiconductor material homogeneous with the single crystal ingot 1.

The surface roughness of the joint surface 10 of the single crystal block 1 is 0.3nm-10nm, the flatness is 1-10 microns, and the particle size of the powder 6 is larger than that of the joint surface.

The assembly process of the structure is as follows:

1: the single crystal blocks 1 and the connection surfaces 10 thereof are processed, the connection surfaces 10 of the two single crystal blocks 1 which are connected with each other are common crystal faces of the two single crystal blocks 1, two different crystal orientations on the crystal faces are kept to be basically consistent (the crystal orientation difference is less than 0.05 degrees), and the approximate consistency of the periodicity of the overall crystal lattice arrangement on different single crystal blocks is realized.

And carrying out mechanical chemical polishing on the connecting surface 10, wherein the surface roughness of the connecting surface 10 is 0.3nm-10nm, and the flatness is 1-10 microns.

If the clamp 4 is required to be fixed, a clamping groove is machined in the single crystal block 1, and a clamp 4 is machined, wherein the size of the clamp 4 is determined according to the size of the combined single crystal blocks 1.

The fixture 4 is cut by using a semiconductor material with the same material as the crystal block 1, and is matched with the monocrystal 1 for assembly, so that stress defects caused by different thermal expansion coefficients of different materials are prevented.

The location of the machined groove is such that the clamp 4 is oriented perpendicular to the attachment surface 10 to ensure that the force of the clamp 4 is directed perpendicular to the attachment surface 10.

The monocrystalline blocks 1 are joined together by means of clamps 4, as shown in fig. 3, the clamps 4 being arranged at respective upper and lower positions of the assembly of the monocrystalline blocks 1, which ensures the joining accuracy and also ensures that the joint faces 10 are not liable to move relatively under hot isostatic pressing.

Fig. 3 is a schematic view of two single crystal blocks 1 being spliced together.

Fig. 4 is a schematic view showing a plurality of single crystal blocks 1 spliced together according to another embodiment. In the embodiment of fig. 4, the outer periphery of the outermost single crystal block 1 is filled with the filling block 12 so that the overall shape fits the package. The filling block 12 is cut out of a semiconductor material having the same material as the ingot 1.

In order to ensure that the single crystal blocks 1 are not dislocated in the packaging process after combination and fixation, a substrate 11 is arranged below the combination of the fixed single crystal blocks 1, and the substrate 11 is made of a semiconductor material which is the same as the material of the single crystal blocks 1 and can be a single crystal or polycrystalline material.

The quartz cloth or the quartz fiber wire is washed by an organic solvent and treated in vacuum at high temperature to remove oil stains on the surface, and meanwhile, the quartz wire which is easy to fall off is removed by vibration and blowing. The effect is to prevent contamination and to prevent the connecting surface from entering liquid and other impurities.

The assembled and fixed single crystal blocks 1 are tightly wrapped by a quartz wrapping layer 5.

After the package is finished, the semiconductor material is fastened by a fastening collar 2, a fastening collar protective layer 9 is arranged outside the fastening collar 2, and a boron oxide coating with the thickness of 0.5-1mm is arranged on the surface of the fastening collar 2 and can prevent metal from polluting the semiconductor material.

And obtaining a crystal block unit after the assembly is finished.

The ingot unit is placed in a sheath main body 8, the periphery of the sheath main body is filled with semiconductor material powder which is the same as the single crystal ingot 1 to form a semiconductor powder layer 6, the ingot unit is positioned at the central position of the sheath main body 8 (without precision, the crystal unit is approximately positioned at the center), and the semiconductor powder is compacted, as shown in figures 1, 2 and 4.

In fig. 1, since the clamps 4 are provided on both the upper and lower sides of the single crystal block 1, the substrate 11 may not be provided; in fig. 2, a substrate 11 is provided.

In fig. 4, the jig 4 is not provided, and the substrate 11 is provided.

In the embodiment of fig. 4, the combination of the single crystal blocks 1 may be fixed by using the jig 4 at the same time.

In the figures 1 and 2, the sheath protective layer 7 is a boron oxide coating with the thickness of 0.5-1mm, and the edge sealing 3-1 of the sheath upper cover and the edge sealing 8-1 of the sheath main body are not provided with the boron oxide coating.

And welding the sealing edge 3-1 of the upper cover of the sheath and the sealing edge 8-1 of the main body of the sheath by using laser or electron beams to finish the assembly of the structure.

Pretreatment:

after the structure is assembled, the whole sheath is vacuumized to 10 degrees through the air exhaust hole 3-2^-3To 10^-6Pa, and carrying out preheating treatment at the temperature of 400 ℃.

And extruding the air exhaust hole 3-2, then welding and sealing the air exhaust hole 3-2 by laser or electron beams, and detecting leakage.

After the pretreatment is finished, the whole structure is placed in a hot isostatic pressing furnace body for heating and pressure treatment, so that atoms on the connecting surface 10 are in diffusion connection under a high-temperature and high-pressure environment.

The position is maintained throughout the hot isostatic pressing process: the assembly structure for hot isostatic pressing of high purity semiconductor single crystals is always placed in the hot isostatic pressing furnace in the direction in which single crystal ingot 1 is located above homogeneous semiconductor substrate 11.

Claims (8)

1. The structure comprises a capsule and a crystal block unit arranged inside the capsule, wherein the capsule consists of a capsule main body (8) and a capsule upper cover (3), and is characterized in that:

the sheath main body (8) or the sheath upper cover (3) is provided with an air exhaust hole (3-2), and the inner surfaces of the sheath main body (8) and the sheath upper cover (3) are provided with a sheath protective layer (7);

the crystal block unit comprises a plurality of single crystal blocks (1), the single crystal blocks (1) are combined through connecting surfaces (10) and are fixed through a clamp (4) and/or a filling block (12), and a quartz wrapping layer (5) is arranged on the outer surface of the fixed single crystal block (1) combination.

2. The fitting structure according to claim 1, wherein: the clamp (4) and/or the filling block (12) are made of semiconductor materials which are the same as the single crystal block (1).

3. The fitting structure according to claim 1, wherein: and a fastening collar (2) and a fastening collar protective layer (9) are arranged outside the quartz wrapping layer (5) of the crystal block unit.

4. The fitting structure according to claim 1, wherein: the crystal block unit is arranged at the central position of the sheath body (8), and the periphery of the crystal block unit is filled with semiconductor material powder which is homogeneous with the crystal block (1).

5. The fitting structure according to claim 1 or 2, characterized in that: the surface roughness of the connecting surface (10) of the single crystal block (1) is 0.3nm-10nm, and the flatness is 1-10 microns.

6. The fitting structure according to claim 5, wherein: the grain size of the semiconductor powder is larger than the flatness of the connection surface.

7. The fitting structure according to claim 3, wherein: the surface of the fastening clamping ring (2) is provided with a boron oxide coating, and the thickness of the boron oxide coating is 0.5-1 mm.

8. The fitting structure according to claim 1, wherein: a substrate (11) is provided under the single crystal block (1) fixed by the jig (4) and/or the filling block (12), and the substrate (11) is made of a semiconductor material having the same material as that of the single crystal block (1).

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