CN1476046A

CN1476046A - Preparation method of ZnAl0/alpha-Al0composite base material

Info

Publication number: CN1476046A
Application number: CNA031296017A
Authority: CN
Inventors: 军徐; 徐军; 王海丽; 周圣明; 杨卫桥; 彭观良; 周国清; 宋词; 杭寅; 蒋成勇; 司继良; 赵广军
Original assignee: Shanghai Institute of Optics and Fine Mechanics of CAS
Current assignee: Shanghai Institute of Optics and Fine Mechanics of CAS
Priority date: 2003-06-27
Filing date: 2003-06-27
Publication date: 2004-02-18
Anticipated expiration: 2023-06-27
Also published as: CN1207756C

Abstract

The method includes the following steps: placing ZnAl2O4 and ZnO mixed material block with gas holes into platinum crucible, placing or hanging either double face polished or single face polished sapphire a-Al2O3 wafer on platinum filament, setting crucible cover blanketed with ZnAl2O4 and ZnO mixed power and thermocouple and setting platinum cover on crucible top for seal, placing it into resistance furnace, heating the furnace temperature up to 1000-1400 deg., keeping it constant for 20-100 hour to let ZnO diffuse into a-Al2O3 uafer and decreasing temperature to obtain ZnA2O4/a-Al2O3 compound substrate material.

Description

ZnAl 2O 4/ α-Al 2O 3The compound lining material preparation method

Technical field

The present invention relates to a kind of ZnAl ₂O ₄/ α-Al ₂O ₃The preparation method of compound lining material.ZnAl ₂O ₄/ α-Al ₂O ₃Compound lining material is mainly as the epitaxial growth of InN-GaN base blue-light semiconductor.

Background technology

III hi-nitride semiconductor material InN-GaN has excellent characteristic, as the optical transition probability of stable physics and chemical property, high thermal conductance and high electron saturation velocities, direct band gap material a high order of magnitude than indirect band gap, therefore, broad-band gap InN-GaN base semiconductor is demonstrating wide application prospect aspect short-wave long light-emitting diode, laser and ultraviolet detector and the high-temperature electronic device.Because the InN-GaN fusing point is higher, N ₂Saturated vapor pressure is bigger, and InN-GaN body single crystal preparation is very difficult, so InN-GaN generally grows with epitaxy technology on foreign substrate.

White gem crystal (α-Al ₂O ₃) be easy to preparation, low price, and have the good characteristics such as high-temperature stability, α-Al ₂O ₃It is at present the most frequently used InN-GaN epitaxial substrate material (referring to Jpn.J.Appl.Phys., the 36th volume,, the 1568th page in 1997).

In recent years, utilize ZnO to obtain widely research as buffer growth GaN film because the lattice mismatch of ZnO and GaN littler (2.2%) and identical stacking sequence is arranged, although take ZnO as cushion at α-Al ₂O ₃Complicated variation has taken place but abundant evidence shows ZnO in the high-quality GaN film that utilized the hydride gas-phase epitaxy technology growth on the substrate in the GaN growth course.At first, ZnO is at high temperature unstable, and decomposition reaction takes place easily, causes Zn doping in the GaN epitaxial loayer; Secondly, ZnO at high temperature with α-Al ₂O ₃The reaction of substrate generation solid-state diffusion makes α-Al ₂O ₃Spinelle ZnAl has appearred on the substrate ₂O ₄Cover layer.More than reaction makes the ZnO cushion be difficult to be adopted by other GaN high growth temperature technology.Recently, the people such as the Gu Shulin of Nanjing of China university, professor Zhang Rong point out ZnAl by experiment ₂O ₄Can be for GaN growth provide low surface energy and Lattice Matching preferably, be conducive to the high-quality extension (referring to MRS Internet J.NitrideSemiconduct.Res., the 5th rolls up, 2000, the 15th page) of GaN.Calendar year 2001, they proposed again to prepare ZnAl with pulsed laser deposition (PLD:pulsed laser deposition) technology ₂O ₄/ α-Al ₂O ₃Compound substrate, its key idea are to utilize ZnO and α-Al ₂O ₃Solid phase reaction is earlier at α-Al ₂O ₃Substrate surface making ZnO film, rear preparation ZnAl ₂O ₄Tectal two-step process, and this compound substrate is successfully applied to GaN epitaxial growth (referring to the semiconductor journal, the 22nd the volume, the 8th phase, calendar year 2001, the 1025th page).

α-Al formerly ₂O ₃Substrate and pulsed laser deposition (PLD:pulsed laser depposition) technology prepares ZnAl ₂O ₄/ α-Al ₂O ₃The remarkable shortcoming that compound substrate exists is: (1) uses α-Al ₂O ₃Make substrate, α-Al ₂O ₃And the lattice mismatch between the GaN makes the GaN film of preparation have higher dislocation density and a large amount of point defects up to 14%; (2) pulsed laser deposition technique has adopted elder generation at α-Al ₂O ₃Substrate surface making ZnO film, rear preparation ZnAl ₂O ₄Tectal two-step process, complex process, quality instability.

Summary of the invention

The technical problem to be solved in the present invention is to overcome the shortcoming of above-mentioned prior art, and a kind of ZnAl is provided ₂O ₄/ α-Al ₂O ₃The preparation method of compound lining material.

ZnAl of the present invention ₂O ₄/ α-Al ₂O ₃The preparation method of compound lining material utilizes vapor transport equilibration (Vapor Transport Equilibration is called for short VTE) technology, in the atmosphere of high temperature, rich zinc, passes through Zn ²⁺The diffusion of ion makes ZnO and α-Al ₂O ₃Solid phase reaction, preparation has ZnAl ₂O ₄Tectal α-Al ₂O ₃Compound lining material (ZnAl ₂O ₄/ α-Al ₂O ₃).

ZnAl of the present invention ₂O ₄/ α-Al ₂O ₃The preparation method of compound lining material comprises the following steps:

1. in platinum crucible, be placed with the ZnAl with pore ₂O ₄With the ZnO mixture block; ,

2. with the sapphire α-Al of twin polishing or single-sided polishing ₂O ₃Wafer is put or is hung on the platinum wire, adds to be coated with ZnAl ₂O ₄With the crucible cover of ZnO mixed powder and thermocouple, the crucible top adds airtight being placed in the resistance furnace of platinum lid;

3. resistance furnace is heated to 1000～1400 ℃, constant temperature 20～100 hours, and ZnO is diffused into α-Al ₂O ₃In the wafer;

4. cooling can obtain ZnAl ₂O ₄/ α-Al ₂O ₃Compound lining material.

Described ZnAl ₂O ₄With the weight ratio of ZnO mixture block (3) be: ZnAl ₂O ₄/ ZnO=(0～95): (100～5).

Described resistance furnace also can silicon carbide rod furnace or the replacement of Si-Mo rod stove.

The present invention and technology α-Al formerly ₂O ₃Substrate and pulsed laser deposition (PLD) technology prepares ZnAl ₂O ₄/ α-Al ₂O ₃Compound substrate is compared, and its advantage is: (1) has overcome formerly technology α-Al ₂O ₃The problem that substrate lattice mismatch degree is big can be used for high quality InV-GaN thin film epitaxial growth.(2) utilize ZnO and α-Al ₂O ₃Solid phase reaction, preparation ZnAl ₂O ₄Cover layer, a step finishes, and has avoided pulsed laser deposition technique to adopt elder generation at α-Al ₂O ₃Substrate surface making ZnO film, rear preparation ZnAl ₂O ₄Tectal two-step process, technology is simple, easy to operate, steady quality.

Description of drawings

Fig. 1 is a vapor transport equilibration device schematic diagram.

Embodiment

See also earlier Fig. 1, used vapor transport equilibration (VTE) technology of the present invention prepares compound lining material ZnAl ₂O ₄/ α-Al ₂O ₃The device schematic diagram see Fig. 1, in the platinum crucible 1, be placed with the ZnAl with certain proportioning of pore 2 ₂O ₄With ZnO mixture block 3, material piece 3 tops are platinum wires 4, the sapphire α-Al of twin polishing or single-sided polishing ₂O ₃Wafer 5 is placed on the platinum wire 4, and platinum sheet 6 and ZnAl are arranged at material piece 3 tops ₂O ₄Cover with ZnO mixed powder 7, thermocouple 8 inserts in the powders 7, and crucible 1 top adds platinum and covers 9 airtight.

Vapor transport equilibration (VTE) technology is a kind of mass transport process, so the crucible planted agent ensures enough ZnO supplys, and secondly, the balance of gas phase is to rely on ZnO continuously from ZnAl ₂O ₄Keep with volatilization in the ZnO mixture block, for preventing that mixture block surface ZnO from exhausting the balance that causes and destroying, should make the mixture block have loose structure.To increase the evaporation surface of ZnO as far as possible.

Sapphire α-Al ₂O ₃Wafer placement or hang in the airtight platinum crucible, then airtight platinum crucible is put into electric furnace or silicon carbide rod furnace or Si-Mo rod stove, be heated to predetermined equilibrium temperature, the insulation regular hour is carried out the gas-liquid equilibrium diffusion, in order to accelerate diffusion process and structural adjustment process, should choose as far as possible high equilibrium temperature, generally choose 1000～1400 ℃.

Vapor transport equilibration of the present invention (VTE) technology prepares compound lining material ZnAl ₂O ₄/ α-Al ₂O ₃The concrete technology flow process as follows:

＜1〉in platinum crucible 1, is placed with the ZnAl with pore 2 ₂O ₄With ZnO mixture block 3, choose ZnAl ₂O ₄/ ZnO=(0～95): (100～5) weight ratio.

＜2〉with the sapphire α-Al of twin polishing or single-sided polishing ₂O ₃Wafer is put or is hung on the platinum wire 4, adds to be coated with ZnAl ₂O ₄With the crucible cover of ZnO mixed powder (proportioning with＜1 〉) and thermocouple, the crucible top adds platinum and covers airtightly, places resistance furnace.

＜3〉be heated to about 1000～1400 ℃, constant temperature 20～100 hours, ZnO is diffused into α-Al ₂O ₃In the wafer.Thereby obtained ZnAl ₂O ₄/ α-Al ₂O ₃Compound lining material.

Lift specific embodiment explanation preparation ZnAl with above-mentioned vapor transport equilibration device and concrete technological process ₂O ₄/ α-Al ₂O ₃The compound lining material process is as follows:

In φ 100 * 80mm De gold crucible, be placed with the ZnAl with pore₂O ₄With the ZnO mixture block, choose ZnAl ₂O ₄/ ZnO=75: 25 weight ratios.Sapphire α-Al with twin polishing or single-sided polishing ₂O ₃Wafer is put or is hung on the platinum wire, adds to be coated with ZnAl ₂O ₄With the crucible cover of ZnO mixed powder and thermocouple, it is airtight that the crucible top adds the platinum lid, places resistance furnace.The heating resistor stove is warming up to 1250 ℃, constant temperature 100 hours, and ZnO is diffused into α-Al ₂O ₃In the wafer.Thereby obtained ZnAl ₂O ₄/ α-Al ₂O ₃Compound lining material.This compound substrate can be used for growing high-quality InN-GaN thin film epitaxial growth.

Claims

1, a kind of ZnAl ₂O ₄/ α-Al ₂O ₃The preparation method of compound lining material is characterized in that it comprises the following steps:

1. in platinum crucible (1), be placed with the ZnAl of band pore (2) ₂O ₄With ZnO mixture block (3);

2. with the sapphire α-Al of twin polishing or single-sided polishing ₂O ₃Wafer (5) is put or is hung on the platinum wire (4), adds to be coated with ZnAl ₂O ₄With the crucible cover of ZnO mixed powder (7) and thermocouple (8), it is airtight that the crucible top adds platinum lid (9), places resistance furnace;

4. cooling can obtain ZnAl ₂O ₄/ α-Al ₂O ₃Compound lining material.

2, ZnAl according to claim 1 ₂O ₄/ α-Al ₂O ₃The preparation method of compound lining material is characterized in that described ZnAl ₂O ₄With the weight ratio of ZnO mixture block (3) be: ZnAl ₂O ₄/ ZnO=(0～95): (100～5).

3, ZnAl according to claim 1 ₂O ₄/ α-Al ₂O ₃The preparation method of compound lining material is characterized in that described resistance furnace also can silicon carbide rod furnace or the replacement of Si-Mo rod stove.