Crucible for growing indium phosphide crystals

Abstract

The invention provides a crucible for growing indium phosphide crystals, which comprises a carrier crucible and a diamond coating layer / coating body, the diamond coating layer / coating body is arranged on the inner surface of the carrier crucible, the material of the carrier crucible is any one of graphite, quartz, silicon carbide or boron nitride, and the diamond coating layer / coating body is arranged on the inner surface of the carrier crucible. The thickness d of the diamond coating layer or the diamond coating layer arranged on the surface of the diamond coating body is not less than 0.5 [mu] m and not more than 100 [mu] m, placing an indium phosphide polycrystal material in the crucible, then placing the crucible in a high-pressure reaction kettle, setting process parameters, and carrying out single crystal growth, the problems that in the prior art, indium phosphide crystals obtained through growth are large in internal stress and many in dislocation, and crystal lattices are prone to distortion are solved.

Description

Technical Field

[0001] The invention relates to the technical field of indium phosphide crystal preparation, in particular to a crucible for growing indium phosphide crystals. Background Art

[0002] Indium phosphide (InP), as one of the second-generation compound semiconductor materials, is an ideal substrate material for growing ternary alloy InGaAs and quaternary alloy InGaAsP. Due to its superior properties such as large bandgap and high electron mobility, it is widely used in many technical fields such as light-emitting diodes, optical communications, microwave devices, millimeter-wave devices, and radiation-resistant solar cells.

[0003] At present, the vertical gradient solidification method (VGF) and the liquid-sealed Czochralski method (LEC) are mostly used to prepare InP crystals. The crucible materials used are mostly quartz, graphite, and boron nitride. Quartz crucibles have problems such as low thermal conductivity and the introduction of silicon impurities. Although graphite has high thermal conductivity, the graphite surface is prone to powdering and pollution. The pBN crucible has become the preferred material for InP growth crucibles due to its high purity and good thermal stability. However, its thermal conductivity in the "c" direction is only about 2.6W / m·k, and the heat transfer along the lateral thickness of the crucible is extremely low, resulting in a large temperature difference in the lateral direction, which makes the grown InP crystals have large internal stress, many dislocations, and the lattice is also prone to distortion. Summary of the invention

[0004] The present invention provides a crucible for growing indium phosphide crystals and a method for preparing indium phosphide crystals, which solves the problems of large internal stress, many dislocations, and easy lattice distortion of the indium phosphide crystals grown in the prior art. The technical solution of the present invention is achieved as follows:

[0005] A crucible for growing indium phosphide crystals, comprising a carrier crucible and a diamond coating layer / coating body, wherein the diamond coating layer / coating body is arranged on the inner surface of the carrier crucible, the carrier crucible is made of any one of graphite, quartz, silicon carbide or boron nitride, the thickness of the diamond coating layer or the diamond coating layer arranged on the surface of the diamond coating body is d, then 0.5 μm ≤d≤ 100 μm .

[0006] As a preferred technical solution, it comprises an inner diamond crucible and an outer quartz ampoule, and a diamond film is deposited on the inner surface of the diamond crucible by chemical vapor deposition.

[0007] As a preferred technical solution, the size of the diamond crucible is 4 inches and the height is 300 mm.

[0008] As a preferred technical solution, the diamond crucible has a thickness of 0.6 mm after demoulding.

[0009] As a preferred technical solution, a crucible for growing indium phosphide crystals adopts a vertical gradient solidification method to grow indium phosphide crystals.

[0010] As a preferred technical solution, a quartz crucible body and a diamond film coated on the inner surface thereof, wherein a layer of diamond film is deposited on the inner surface of the quartz crucible body by chemical vapor deposition.

[0011] As a preferred technical solution, the size of the diamond crucible is 6 inches and the height is 200 mm.

[0012] As a preferred technical solution, the diamond film thickness of the diamond composite crucible is 50 μm.

[0013] As a preferred technical solution, a crucible for growing indium phosphide crystals adopts a liquid-sealed pulling method to grow indium phosphide crystals.

[0014] Compared with the prior art, the present invention has the following beneficial effects: utilizing the advantages of diamond such as high thermal conductivity, good thermal stability, good chemical thermostability and smooth surface, the indium phosphide crystals grown in the prior art have large internal stress, many dislocations and the lattice is easily distorted. The indium phosphide crystals obtained by using a crucible for growing indium phosphide crystals in the present invention have the advantages of small internal stress, low dislocation density, no lattice distortion and high single crystal yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 A schematic diagram of a diamond crucible for growing indium phosphide crystals using the VGF method in Example 1 of this patent;

[0017] Figure 2 Schematic diagram of a diamond composite crucible for growing indium phosphide crystals using the LEC method in Example 2 of this patent. DETAILED DESCRIPTION

[0018] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] Example 1.

[0020] A crucible for growing indium phosphide crystals: a diamond crucible is used to grow indium phosphide crystals. First, indium phosphide polycrystalline material is placed in the diamond crucible, and then the diamond crucible is placed in a high-pressure reactor, and process parameters are set to perform single crystal growth.

[0021] The diamond crucible is a diamond crucible obtained by depositing a diamond film on the inner wall of a carrier crucible by chemical vapor deposition (VGF) in a vapor deposition vacuum furnace, and then demolding the film after a certain thickness is deposited;

[0022] The carrier crucible is made of graphite, quartz, silicon carbide or boron nitride;

[0023] The size of the diamond crucible is 4 inches and the height is 300 mm. The diamond crucible used for growing indium phosphide crystals has a thickness of 0.6 mm after demoulding.

[0024] Example 2.

[0025] A crucible for growing indium phosphide crystals: a diamond crucible is used to grow indium phosphide crystals. First, indium phosphide polycrystalline material is placed in the diamond crucible, and then the diamond crucible is placed in a high-pressure reactor, and process parameters are set to perform single crystal growth.

[0026] The diamond crucible is a diamond composite crucible obtained by depositing a diamond film on the inner wall of the carrier crucible by chemical vapor deposition in a vapor deposition vacuum furnace.

[0027] Wherein, the carrier crucible is made of graphite, quartz, silicon carbide or boron nitride;

[0028] The size of the diamond crucible is 6 inches and the height is 200 mm; the thickness of the diamond film of the diamond composite crucible is 50 μm.

[0029] Compared with the prior art, the solution of the present application utilizes the advantages of diamond such as high thermal conductivity, good thermal stability, good chemical thermostability and smooth surface. The indium phosphide crystals grown in the prior art have large internal stress, many dislocations and lattice distortion. The indium phosphide crystals prepared by using a crucible for growing indium phosphide crystals in the present solution have the advantages of small internal stress, low dislocation density, no lattice distortion and high single crystal yield.

[0030] In order to verify the above technical effects, the applicant designed multiple groups of experiments for comparison, selected multiple groups of comparative proportions, and analyzed them from multiple dimensions such as head electron mobility, tail electron mobility, head carrier concentration, tail carrier concentration, head dislocation density, tail dislocation density and average dislocation density.

[0031] For Example 1, the experimental results are as follows:

[0032]

[0033] For Example 2, the experimental results are as follows:

[0034]

[0035] It can be found from the above table that the indium phosphide crystals prepared by the crucible for growing indium phosphide crystals and the indium phosphide crystal preparation method of the present scheme have greatly improved core indicator parameters in multiple dimensions such as head electron mobility, tail electron mobility, head carrier concentration, tail carrier concentration, head dislocation density, tail dislocation density and average dislocation density compared with the control group data, which solves the problems of large internal stress, many dislocations and easy lattice distortion in indium phosphide crystals. The prepared indium phosphide crystals have the advantages of small internal stress, low dislocation density, no lattice distortion and high single crystal yield.

[0036] There are many more sets of experimental data mentioned above, all of which can verify the above conclusions. This article will not list or elaborate on them one by one.

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A crucible for growing indium phosphide crystals, characterized in that: It comprises a carrier crucible and a diamond coating layer / coating body, wherein the diamond coating layer / coating body is arranged on the inner surface of the carrier crucible, the carrier crucible is made of any one of graphite, quartz, silicon carbide or boron nitride, the thickness of the diamond coating layer or the diamond coating layer arranged on the surface of the diamond coating body is d, then 0.5μm≤d≤100μm.

2. A crucible for growing indium phosphide crystals as claimed in claim 1, characterized in that: The invention comprises an inner diamond crucible and an outer quartz ampoule bottle, wherein a diamond film is deposited on the inner surface of the diamond crucible by chemical vapor deposition.

3. A crucible for growing indium phosphide crystals as claimed in claim 2, characterized in that: The diamond crucible has a size of 4 inches and a height of 300 mm.

4. A crucible for growing indium phosphide crystals as claimed in claim 2, characterized in that: The diamond crucible has a thickness of 0.6 mm after demoulding.

5. A crucible for growing indium phosphide crystals as claimed in claim 2, characterized in that: The crucible for growing indium phosphide crystals adopts a vertical gradient solidification method to grow indium phosphide crystals.

6. A crucible for growing indium phosphide crystals as claimed in claim 1, characterized in that: The invention comprises a quartz crucible body and a diamond film coated on the inner surface thereof. A layer of diamond film is deposited on the inner surface of the quartz crucible body by chemical vapor deposition.

7. A crucible for growing indium phosphide crystals as claimed in claim 6, characterized in that: The size of the diamond crucible is 6 inches and the height is 200 mm.

8. A crucible for growing indium phosphide crystals as claimed in claim 6, characterized in that: The diamond film thickness of the diamond composite crucible is 50 μm.

9. A crucible for growing indium phosphide crystals as claimed in claim 6, characterized in that: The crucible for growing indium phosphide crystals adopts a liquid-sealed Czochralski method to grow indium phosphide crystals.

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