CN214361833U

CN214361833U - Gallium boat structure for reducing HVPE epitaxial film defects

Info

Publication number: CN214361833U
Application number: CN202120436381.3U
Authority: CN
Inventors: 张�林; 魏曙亮
Original assignee: Gatt Semiconductor Technology Tongling Co ltd
Current assignee: Gatt Semiconductor Technology Tongling Co ltd
Priority date: 2021-03-01
Filing date: 2021-03-01
Publication date: 2021-10-08
Anticipated expiration: 2031-03-01

Abstract

The utility model discloses a reduce gallium boat structure of HVPE epitaxial film defect, include: a housing; the upper flange end is hermetically arranged at the upper end of the shell; the air inlet pipe is communicated with the center of the upper flange end; the first air inlet and the second air inlet are symmetrically arranged on the upper flange end relative to the air inlet pipe; the multilayer bin is fixedly connected to the bottom of the upper flange end and used for containing gallium, a contraction part is arranged at the bottom of the multilayer bin, and the bottom of the air inlet pipe extends downwards along the axial direction of the multilayer bin and forms a concentric cylindrical cavity with the contraction part; the carrying platform is positioned below the multilayer bin in the shell; and the substrate is arranged on the carrying platform and is opposite to the cylindrical cavity. The beneficial effects of the utility model are that can effectual reduction gallium boat corrode, improve the life of gallium boat, and then reduce epitaxial film defect, improve epitaxial film quality.

Description

Gallium boat structure for reducing HVPE epitaxial film defects

Technical Field

The utility model relates to a gallium boat structure especially relates to a reduce gallium boat structure of HVPE epitaxial film defect.

Background

Wide bandgap semiconductor materials such as GaN, SiC, diamond and ZnO are called third generation semiconductors, and have the excellent performances of larger breakdown voltage, smaller dielectric constant, higher saturated electron drift rate, better heat conductivity, wider energy gap (Eg is more than or equal to 2.3 eV) and the like. Because of the characteristics of more stable chemical property, high temperature resistance and corrosion resistance, the GaN is very suitable for manufacturing high-frequency, high-power and high-density integrated electronic devices.

Because the gallium boat of HVPE is made of quartz, under the condition of high temperature, H₂The gallium boat made of quartz material, especially the quartz tube at the lower end of the gallium boat main body, is corroded very seriously, resulting in a lot of defects of the grown gallium nitride single crystal material.

The Chinese invention patent publication No. CN112210828A discloses a gallium boat structure for reducing the Si content in HVPE epitaxial film, the structure is a multilayer structure, the outer layer is a quartz tube, the left end is sealed on the flange of HVPE, and the structure plays a role in supporting; the middle layer is provided with two pyrolytic boron nitride tubes which are a first pyrolytic boron nitride tube and a second pyrolytic boron nitride tube respectively and prevent corrosive gas Cl2 from contacting with the quartz tube, and the inner layer is a pyrolytic boron nitride crucible used for containing liquid metal gallium; the first pyrolytic boron nitride tube is sleeved in the quartz tube; the second pyrolytic boron nitride tube is sleeved in the first pyrolytic boron nitride tube; the pyrolytic boron nitride crucible is placed inside a second pyrolytic boron nitride tube. The structure is a gallium boat structure used for a Halide Vapor Phase Epitaxy (HVPE) furnace with a horizontal structure, and has little reference significance to a HVPE furnace with a vertical structure.

SUMMERY OF THE UTILITY MODEL

The utility model provides a solve the problem that HVPE method growth gallium nitride in-process produced too much defect, provided a novel gallium boat structure, be a gallium boat structure that reduces epitaxial film defect. The gallium boat is suitable for HVPE machine table with vertical structure, and can greatly reduce the defect of gallium nitride and improve the quality of epitaxial film of gallium nitride, thereby being beneficial to manufacturing electronic devices with high frequency, high power and high density integration and improving the performance of the devices.

The technical scheme of the utility model is that: a gallium boat structure for reducing HVPE epitaxial film defects, comprising: a housing; the upper flange end is hermetically arranged at the upper end of the shell; the air inlet pipe is communicated with the center of the upper flange end; the first air inlet and the second air inlet are symmetrically arranged on the upper flange end relative to the air inlet pipe; the multilayer bin is fixedly connected to the bottom of the upper flange end and used for containing gallium, a contraction part is arranged at the bottom of the multilayer bin, and the bottom of the air inlet pipe extends downwards along the axial direction of the multilayer bin and forms a concentric cylindrical cavity with the contraction part; the carrying platform is positioned below the multilayer bin in the shell; and the substrate is arranged on the carrying platform and is opposite to the cylindrical cavity.

In the scheme, the contraction part is a detachable quartz tube.

In the scheme, the air inlet pipe is a quartz pipe.

In the scheme, the shell is a quartz cover.

In the scheme, the multi-layer bin is provided with at least three layers, and each layer is provided with a through hole.

The improvement of the scheme is that a lining for containing the cylindrical cavity and the carrying platform is arranged below the inner wall of the shell.

In the scheme, the bottom of the shell is fixedly connected with a lower flange.

The beneficial effects of the utility model are that can effectual reduction gallium boat corrode, improve the life of gallium boat, and then reduce epitaxial film defect, improve epitaxial film quality.

Drawings

FIG. 1 is a schematic view of the present invention;

FIG. 2 is a schematic view of the housing of FIG. 1;

in the figure, 1, a shell, 2, an upper flange end, 3, an air inlet pipe, 4, a first air inlet, 5, a second air inlet, 6, a multi-layer bin, 7, a contraction part, 8, a carrying platform, 9, a substrate, 10, an inner lining, 11 and a high-temperature furnace.

Detailed Description

The technical solution in the embodiment of the present invention is clearly and completely described below with reference to the accompanying drawings. It is to be understood that the embodiments described are only some embodiments of the invention, and not all embodiments. Based on the embodiments in the present invention, all other embodiments of the ordinary skilled person in the art without creative work belong to the protection scope of the present invention.

As shown in fig. 1, the utility model comprises: a housing 1; an upper flange end 2, which is hermetically mounted at the upper end of the housing; the air inlet pipe 3 is communicated with the center of the upper flange end; the first air inlet 4 and the second air inlet 5 are symmetrically arranged on the upper flange end relative to the air inlet pipe; the multilayer bin 6 is fixedly connected to the bottom of the upper flange end and used for containing gallium, a contraction part 7 is arranged at the bottom of the multilayer bin, and the bottom of the air inlet pipe extends downwards along the axial direction of the multilayer bin and forms a concentric cylindrical cavity with the contraction part; the carrier 8 is positioned below the multilayer bin in the shell; and the substrate 9 is arranged on the carrier and is opposite to the cylindrical cavity.

Specifically, the contraction part is a detachable quartz tube, the air inlet pipe is a quartz tube, the shell is a quartz cover, and the top and the bottom of the shell are sealed and fixed on the flange to play roles of supporting and isolating protection; the contraction part is a detachable quartz tube, so that the disassembly and maintenance are convenient; multilayer storehouse can have three-layer, four-layer or even more multilayer, and every layer all can be used for holding liquid metal gallium, and every layer all is equipped with the passageway that supplies the intake pipe to pass through, and every layer still is equipped with the through-hole in addition and is used for guiding gaseous contraction portion from multilayer storehouse to flow, and the contraction portion indicates to compare with multilayer storehouse's body, and the diameter shrink forms columniform pipeline, forms inside and outside clearance fit's concentric cylinder chamber with the intake pipe.

The working principle of the utility model is as follows: the shell is placed in the multi-temperature-zone high-temperature furnace 11, the upper end and the lower end of the shell are respectively sealed by flanges, special gases HCl, H2, N2 and NH3 are introduced from the upper flange end, specifically, H2, N2 and NH3 are input through a first air inlet, HCl is input through a second air inlet, H2 and N2 are input through air inlet pipes, and tail gas at the lower end is exhausted. Wherein HCl reacts with gallium in the multi-layer bin to generate gallium chloride, and the gallium chloride reacts with NH3 on the carrying table to generate gallium nitride which is deposited on the surface of the substrate. The substrate is placed on a stage. Generally, the gallium boat is made of quartz material, and under high temperature conditions, H2 can cause corrosion to the quartz, especially to the quartz tube at the bottom of the gallium boat, which causes impurity elements to be heavily doped into the surface of the epitaxial film, thus forming surface defects. In order to reduce the surface defects of the epitaxial film, the quartz tube needs to be replaced in time, and the gallium boat and the quartz cover need to be replaced periodically. Therefore, the utility model adopts a multilayer structure, the outer layer is a quartz cover, the upper end is sealed and fixed on the flange, and the functions of supporting and isolating protection are achieved; the middle layer is a gallium boat main body, the upper end of the main body is provided with a multi-layer bin for containing liquid metal gallium, the lower end of the main body is provided with a quartz tube for stabilizing air flow, the lower end of the quartz tube is changed into a detachable quartz tube, and the quartz tube can be replaced in time when gas corrosion is serious; the gas inlet pipe is a quartz pipe and mainly plays a role of beam current to form a stable gas column. The detachable quartz tube faces the carrier, so that gallium nitride can reach the substrate at a certain flow rate and be deposited on the surface of the substrate.

Claims

1. A gallium boat structure for reducing HVPE epitaxial film defects is characterized in that: the method comprises the following steps: a housing (1); an upper flange end (2) which is hermetically mounted at the upper end of the housing; the air inlet pipe (3) is communicated with the center of the upper flange end; the air inlet structure comprises a first air inlet (4) and a second air inlet (5), wherein the first air inlet and the second air inlet are symmetrically arranged on the upper flange end relative to an air inlet pipe; the multilayer bin (6) is fixedly connected to the bottom of the upper flange end and used for containing gallium, a contraction part (7) is arranged at the bottom of the multilayer bin, and the bottom of the air inlet pipe extends downwards along the axial direction of the multilayer bin and forms a concentric cylindrical cavity with the contraction part; a carrier (8) located below the multi-layer bin within the housing; and the substrate (9) is arranged on the carrying platform and is opposite to the cylindrical cavity.

2. The gallium boat structure for reducing HVPE epitaxial film defects according to claim 1, wherein: the constriction is a detachable quartz tube.

3. The gallium boat structure for reducing HVPE epitaxial film defects according to claim 1, wherein: the gas inlet pipe is a quartz pipe.

4. The gallium boat structure for reducing HVPE epitaxial film defects according to claim 1, wherein: the housing is a quartz envelope.

5. The gallium boat structure for reducing HVPE epitaxial film defects according to claim 1, wherein: the multi-layer bin is provided with at least three layers, and each layer is provided with a through hole.

6. The gallium boat structure for reducing HVPE epitaxial film defects according to claim 1, wherein: and a lining (10) for accommodating the cylindrical cavity and the carrying platform is arranged below the inner wall of the shell.

7. The gallium boat structure for reducing HVPE epitaxial film defects according to claim 1, wherein: and the bottom of the shell is fixedly connected with a lower flange.