Annealing modification method of iron-doped zinc selenide single crystal

Abstract

The invention belongs to the technical field of crystal annealing, and discloses an annealing modification method of an iron-doped zinc selenide (Fe < 2 + >: ZnSe) single crystal, which comprises the following specific steps: 1, cleaning an annealing quartz tube; and 2, polishing the Fe < 2 + >: ZnSe wafer, fixing the polished wafer at one end of a quartz tube, filling the other end of the quartz tube with high-purity Zn particles, vacuumizing, and sealing the quartz tube in a fusion manner. And 3, putting the sealed quartz tube into a five-section horizontal tube type annealing furnace, setting proper annealing process parameters, and carrying out annealing modification in a Zn atmosphere. The annealing method is simple, efficient and low in cost, the problem that a large number of inclusion phases exist in Fe < 2 + >: ZnSe single crystals grown through a moving heater method can be solved, the inclusion phase removal efficiency reaches up to 100%, and the optical performance of the annealed wafer is excellent.

Description

Technical Field

[0001] The present invention relates to an iron-doped zinc selenide (Fe 2+ :ZnSe) single crystal annealing modification method, specifically involving a Fe 2 + :Methods to eliminate structural defects in ZnSe single crystals, especially inclusion phases. Background Art

[0002] High-performance mid-infrared (3-5 μm) lasers have huge application scenarios in the fields of military, laser radar, and medical treatment. ZnSe crystals doped with divalent transition metal iron ions (Fe 2+ :ZnSe) has excellent properties such as low phonon energy, high thermal conductivity, wide tuning range and high conversion efficiency. It is one of the most effective materials for achieving high-energy mid-infrared laser output.

[0003] Currently, the preparation of Fe 2+ The methods for growing ZnSe crystals mainly include thermal diffusion method, physical vapor transport method, high pressure Bridgman method and mobile heater method. Compared with other methods, the mobile heater method has both zone melting and low temperature characteristics, and can precisely control the concentration and uniformity of doping ions. It is an ideal method for growing high optical quality Fe 2+ : One of the effective technical approaches for growing ZnSe single crystals. 2+ During the ZnSe crystal growth process, flux is introduced to significantly reduce the growth temperature. However, during the crystal growth process, the use of flux can easily lead to the formation of flux inclusion phase inside the crystal, i.e. inclusion phase. 2+ For ZnSe crystals, the formation of inclusion phases causes local inhomogeneity in the crystal, which will cause light scattering and absorption, significantly increasing light loss, increasing the threshold of the prepared optical device, reducing efficiency, and even failing to effectively output lasers. Generally, by optimizing the crystal growth process and improving the smoothness of the microscopic morphology of the growth interface, the formation of inclusion phases can be reduced, but it is difficult to completely eliminate the inclusion phases in the crystal. Annealing technology is an effective technical approach to eliminate structural defects in crystals and achieve crystal modification, but currently there is no method for Fe 2+ The research and development of annealing modification technology for inclusion phase in ZnSe crystals has not been reported, which seriously limits the development of high optical quality Fe 2+ The preparation of ZnSe single crystals has hindered the commercialization of new high-performance mid-infrared lasers. Summary of the invention

[0004] In view of the technical difficulties mentioned in the background technology, the present invention provides a method for growing iron-doped zinc selenide (FeSe) by a mobile heater method in a Zn atmosphere. 2+ Annealing modification method of ZnSe single crystal to eliminate Fe 2+:The purpose of flux inclusion phase in ZnSe single crystal.

[0005] The present invention adopts the following technical solutions: A kind of iron-doped zinc selenide (Fe 2+ The annealing modification method of ZnSe single crystal is characterized by comprising the following steps: S1, cleaning annealing device; S2. Polishing treatment of Fe 2+ :ZnSe crystal; S3, Fe 2+ : Annealing modification of ZnSe crystals; S4, polishing annealed Fe 2+ :ZnSe crystal;

[0006] In the step S1, first prepare a quartz tube with a diameter of 10 to 20 mm, with one end of the round bottom closed and the other end open; then, ultrasonically clean the quartz tube for 0.5 hours using deionized water (resistivity of about 18 MΩ·cm), acetone, aqua regia (a mixture of hydrochloric acid and nitric acid with a volume ratio of 3:1), and deionized water (resistivity of about 18 MΩ·cm) in sequence; finally, place the quartz tube in a vacuum drying oven and bake it at 120° C. for 5 to 6 hours.

[0007] In step S2, the Fe 2+ : ZnSe wafer, wafer thickness 1-3mm. Use 2500#, 5000# and 7000# sandpaper to polish the wafer surface for 3-10 minutes; then polish with a suspension of 0.2μm aluminum oxide and water for 6-8 minutes, and then polish with a suspension of 30nm aluminum oxide and water for 5 minutes; finally, use deionized water for ultrasonic treatment for 5-10 minutes and dry in a vacuum drying oven.

[0008] In step S3, the treated Fe 2+ : The ZnSe wafer is fixed vertically on the quartz support and placed at one end of the round bottom of the quartz tube cleaned in the first step. Then high-purity metal Zn particles are loaded into the other end of the quartz tube and the quartz tube is evacuated. When the vacuum degree reaches 10 -3 When the temperature is below Pa, the quartz tube mouth is sealed with hydrogen-oxygen flame. The sealed quartz tube is placed in a five-stage horizontal annealing furnace and the annealing parameters are set: Fe 2+ One end of the ZnSe wafer is in the low temperature zone, with a temperature of 900-1000°C and a temperature gradient of 10-50°C, while the end with high-purity Zn particles is in the high temperature constant temperature zone, where the temperature is higher than that of the Fe 2+ The temperature of the ZnSe wafer is 30-80°C, and the annealing time is 24-72 hours; after the annealing is completed, the temperature is lowered to room temperature at a rate of 5-10°C / h.

[0009] In step S5, the annealed wafer is taken out, and the annealed wafer surface is polished for 3 to 5 minutes using the suspension prepared by aluminum oxide with a particle size of 0.2 μm and 30 nm and water in step S2, and then ultrasonicated with deionized water for 5 to 10 minutes, and the wafer is dried in a vacuum drying oven to obtain the modified high optical quality Fe 2+ :ZnSe crystal.

[0010] The beneficial effects of the present invention are as follows: The present invention adopts Zn as the annealing atmosphere source. Under the preferred annealing process, it not only accelerates the reaction between Zn and flux SnSe, but also promotes the diffusion and migration of SnSe flux, thereby successfully eliminating Fe 2+ : SnSe flux inclusion phase in ZnSe crystal. At the same time, combined with the wafer polishing process, the cutting damage layer on the wafer surface is eliminated as much as possible, and the volatilization of the crystal components at high temperature is suppressed to a certain extent, which is conducive to maintaining the stoichiometric ratio of the wafer before and after annealing. The annealing method provided by the present invention can effectively eliminate the Fe grown by the mobile heater method. 2+ :The flux SnSe inclusion phase in ZnSe single crystal is removed with an efficiency of up to 100%, and the optical properties of the annealed wafer are greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction of the solution in the example using the accompanying drawings, so that ordinary technicians in the field can understand the present invention more clearly. The accompanying drawings are only for better illustrating the specific examples and do not limit the solution of the present invention.

[0012] Figure 1 Schematic diagram of the crystal annealing device.

[0013] Figure 2 Fe before and after annealing 2+ : Infrared transmission microscope observation images of the inclusion phase inside ZnSe crystal ((a) before annealing (b) after annealing).

[0014] Figure 3 Fe 2+ :Optical transmittance of ZnSe crystal before and after annealing. DETAILED DESCRIPTION

[0015] The following will be a detailed and clear introduction to the specific example implementation scheme according to the accompanying drawings. The examples shown in the present invention are only for explanation and are not limited to the scheme of the present invention.

[0016] Example 1

[0017] The first step is to clean the annealing device. Prepare a quartz tube with a diameter of 10 mm, with one end closed and the other end open. Use deionized water (resistivity of about 18 MΩ·cm), acetone, aqua regia (a mixture of hydrochloric acid and nitric acid with a volume ratio of 3:1), and deionized water (resistivity of about 18 MΩ·cm) to ultrasonically clean the quartz tube for 0.5 hours; finally, place it in a vacuum drying oven and bake it at 120°C for 5 hours. The second step is to treat the crystal to be annealed. Polishing Fe 2+ : ZnSe wafer, wafer thickness 1mm. Use 2500#, 5000# and 7000# sandpaper to polish the wafer surface for 3 minutes in turn; then polish it with a suspension of aluminum oxide with a particle size of 0.2μm and water for 6 minutes, and then polish it with a suspension of aluminum oxide with a particle size of 30nm and water for 5 minutes, and finally use deionized water ultrasound for 5 minutes and dry it in a vacuum drying oven. The third step is crystal annealing. The treated Fe 2+ : The ZnSe wafer is fixed vertically on the quartz support and placed at one end of the round bottom of the quartz tube cleaned in the first step. Then high-purity metal Zn particles are loaded into the other end of the quartz tube and the quartz tube is evacuated. When the vacuum degree reaches 10 -3 When the temperature is below Pa, the quartz tube mouth is sealed with hydrogen-oxygen flame. The fourth step is to place the vacuumized quartz tube in a five-stage horizontal annealing furnace and set the annealing parameters: Fe is placed in the quartz tube. 2+ One end of the ZnSe wafer is in the low temperature zone, with a temperature of 900°C and a temperature gradient of 10°C, while the end with high-purity Zn particles is in the high temperature constant temperature zone, where the temperature is higher than that of the Fe 2+ The ZnSe wafer is placed at a temperature of 30°C and annealed for 24 hours. After annealing, the temperature is lowered to room temperature at a rate of 5°C / h. In the fifth step, the annealed wafer is taken out, and the slurry prepared by alumina with a particle size of 0.2μm and 30nm and water in the second step is used to polish the surface of the annealed wafer for 3 minutes, and then ultrasonically treated with deionized water for 5 minutes. The wafer is dried in a vacuum drying oven to obtain the modified high optical quality Fe 2+ :ZnSe crystal.

[0018] Example 2

[0019] The first step is to clean the annealing device. Prepare a quartz tube with a diameter of 10 mm, with a closed round bottom at one end and an open end. Use deionized water (resistivity of about 18 MΩ·cm), acetone, aqua regia (a mixture of hydrochloric acid and nitric acid with a volume ratio of 3:1), and deionized water (resistivity of about 18 MΩ·cm) to ultrasonically clean the quartz tube for 0.5 hours; finally, place it in a vacuum drying oven and bake it at 120°C for 6 hours. The second step is to treat the crystal to be annealed. Polishing Fe 2+: ZnSe wafer, wafer thickness 2mm. Use 2500#, 5000# and 7000# sandpaper to polish the wafer surface for 6 minutes in turn; then polish it with a suspension of aluminum oxide with a particle size of 0.2μm and water for 7 minutes, and then polish it with a suspension of aluminum oxide with a particle size of 30nm and water for 5 minutes, and finally use deionized water ultrasound for 8 minutes and dry it in a vacuum drying oven. The third step is crystal annealing. The treated Fe 2+ : The ZnSe wafer is fixed vertically on the quartz support and placed at one end of the round bottom of the quartz tube cleaned in the first step. Then high-purity metal Zn particles are loaded into the other end of the quartz tube and the quartz tube is evacuated. When the vacuum degree reaches 10 -3 When the temperature is below Pa, the quartz tube mouth is sealed with hydrogen-oxygen flame. The fourth step is to place the vacuumized quartz tube in a five-stage horizontal annealing furnace and set the annealing parameters: Fe is placed in the quartz tube. 2+ One end of the ZnSe wafer is in the low temperature zone, with a temperature of 950°C and a temperature gradient of 30°C, while the end with high-purity Zn particles is in the high temperature constant temperature zone, where the temperature is higher than that of the Fe 2+ The ZnSe wafer is placed at a temperature of 50°C and annealed for 48 hours. After annealing, the temperature is lowered to room temperature at a rate of 8°C / h. In the fifth step, the annealed wafer is taken out, and the slurry prepared by alumina with a particle size of 0.2μm and 30nm and water in the second step is used to polish the surface of the annealed wafer for 4 minutes, and then ultrasonically treated with deionized water for 8 minutes. The wafer is dried in a vacuum drying oven to obtain the modified high optical quality Fe 2+ :ZnSe crystal.

[0020] Example 3

[0021] The first step is to clean the annealing device. Prepare a quartz tube with a diameter of 10 mm, with a closed round bottom at one end and an open end. Use deionized water (resistivity of about 18 MΩ·cm), acetone, aqua regia (a mixture of hydrochloric acid and nitric acid with a volume ratio of 3:1), and deionized water (resistivity of about 18 MΩ·cm) to ultrasonically clean the quartz tube for 0.5 hours; finally, place it in a vacuum drying oven and bake it at 120°C for 6 hours. The second step is to treat the crystal to be annealed. Polishing Fe 2+ : ZnSe wafer, wafer thickness 3mm. Use 2500#, 5000# and 7000# sandpaper to polish the wafer surface for 10 minutes in turn; then polish it with a suspension of aluminum oxide with a particle size of 0.2μm and water for 8 minutes, and then polish it with a suspension of aluminum oxide with a particle size of 30nm and water for 5 minutes, and finally use deionized water ultrasound for 10 minutes and dry it in a vacuum drying oven. The third step is crystal annealing. The treated Fe 2+ : The ZnSe wafer is fixed vertically on the quartz support and placed at one end of the round bottom of the quartz tube cleaned in the first step. Then high-purity metal Zn particles are loaded into the other end of the quartz tube and the quartz tube is evacuated. When the vacuum degree reaches 10-3 When the temperature is below Pa, the quartz tube mouth is sealed with hydrogen-oxygen flame. The fourth step is to place the vacuumized quartz tube in a five-stage horizontal annealing furnace and set the annealing parameters: Fe is placed in the quartz tube. 2+ One end of the ZnSe wafer is in the low temperature zone, with a temperature of 1000°C and a temperature gradient of 50°C, while the end with high-purity Zn particles is in the high temperature constant temperature zone, where the temperature is higher than that of the Fe 2+ The ZnSe wafer is placed at a temperature of 80°C and the annealing time is 72 hours. After the annealing is completed, the temperature is lowered to room temperature at a rate of 10°C / h. In the fifth step, the annealed wafer is taken out, and the slurry prepared by the aluminum oxide and water with a particle size of 0.2μm and 30nm in the second step is used to polish the surface of the annealed wafer for 5 minutes, and then ultrasonically treated with deionized water for 10 minutes, and the wafer is dried in a vacuum drying oven to obtain the modified high optical quality Fe 2+ :ZnSe crystal.

[0022] Example 4

[0023] The first step is to clean the annealing device. Prepare a quartz tube with a diameter of 15 mm, with one end closed and the other end open. Use deionized water (resistivity of about 18 MΩ·cm), acetone, aqua regia (a mixture of hydrochloric acid and nitric acid with a volume ratio of 3:1), and deionized water (resistivity of about 18 MΩ·cm) to ultrasonically clean the quartz tube for 0.5 hours; finally, place it in a vacuum drying oven and bake it at 120°C for 5 hours. The second step is to treat the crystal to be annealed. Polishing Fe 2+ : ZnSe wafer, wafer thickness 1mm. Use 2500#, 5000# and 7000# sandpaper to polish the wafer surface for 3 minutes in turn; then polish it with a suspension of aluminum oxide with a particle size of 0.2μm and water for 6 minutes, and then polish it with a suspension of aluminum oxide with a particle size of 30nm and water for 5 minutes, and finally use deionized water ultrasound for 5 minutes and dry it in a vacuum drying oven. The third step is crystal annealing. The treated Fe 2+ : The ZnSe wafer is fixed vertically on the quartz support and placed at one end of the round bottom of the quartz tube cleaned in the first step. Then high-purity metal Zn particles are loaded into the other end of the quartz tube and the quartz tube is evacuated. When the vacuum degree reaches 10 -3 When the temperature is below Pa, the quartz tube mouth is sealed with hydrogen-oxygen flame. The fourth step is to place the vacuumized quartz tube in a five-stage horizontal annealing furnace and set the annealing parameters: Fe is placed in the quartz tube. 2+ One end of the ZnSe wafer is in the low temperature zone, with a temperature of 900°C and a temperature gradient of 10°C, while the end with high-purity Zn particles is in the high temperature constant temperature zone, where the temperature is higher than that of the Fe 2+The ZnSe wafer is placed at a temperature of 30°C and annealed for 24 hours. After annealing, the temperature is lowered to room temperature at a rate of 5°C / h. In the fifth step, the annealed wafer is taken out, and the slurry prepared by alumina with a particle size of 0.2μm and 30nm and water in the second step is used to polish the surface of the annealed wafer for 3 minutes, and then ultrasonically treated with deionized water for 5 minutes. The wafer is dried in a vacuum drying oven to obtain the modified high optical quality Fe 2+ :ZnSe crystal.

[0024] Example 5

[0025] The first step is to clean the annealing device. Prepare a quartz tube with a diameter of 15 mm, with one end closed and the other end open. Use deionized water (resistivity of about 18 MΩ·cm), acetone, aqua regia (a mixture of hydrochloric acid and nitric acid with a volume ratio of 3:1), and deionized water (resistivity of about 18 MΩ·cm) to ultrasonically clean the quartz tube for 0.5 hours; finally, place it in a vacuum drying oven and bake it at 120°C for 6 hours. The second step is to treat the crystal to be annealed. Polishing Fe 2+ : ZnSe wafer, wafer thickness 2mm. Use 2500#, 5000# and 7000# sandpaper to polish the wafer surface for 6 minutes in turn; then polish it with a suspension of aluminum oxide with a particle size of 0.2μm and water for 7 minutes, and then polish it with a suspension of aluminum oxide with a particle size of 30nm and water for 5 minutes, and finally use deionized water ultrasound for 8 minutes and dry it in a vacuum drying oven. The third step is crystal annealing. The treated Fe 2+ : The ZnSe wafer is fixed vertically on the quartz support and placed at one end of the round bottom of the quartz tube cleaned in the first step. Then high-purity metal Zn particles are loaded into the other end of the quartz tube and the quartz tube is evacuated. When the vacuum degree reaches 10 -3 When the temperature is below Pa, the quartz tube mouth is sealed with hydrogen-oxygen flame. The fourth step is to place the vacuumized quartz tube in a five-stage horizontal annealing furnace and set the annealing parameters: Fe is placed in the quartz tube. 2+ One end of the ZnSe wafer is in the low temperature zone, with a temperature of 950°C and a temperature gradient of 30°C, while the end with high-purity Zn particles is in the high temperature constant temperature zone, where the temperature is higher than that of the Fe 2+ The ZnSe wafer is placed at a temperature of 50°C and annealed for 48 hours. After annealing, the temperature is lowered to room temperature at a rate of 8°C / h. In the fifth step, the annealed wafer is taken out, and the slurry prepared by alumina with a particle size of 0.2μm and 30nm and water in the second step is used to polish the surface of the annealed wafer for 4 minutes, and then ultrasonically treated with deionized water for 8 minutes. The wafer is dried in a vacuum drying oven to obtain the modified high optical quality Fe 2+ :ZnSe crystal.

[0026] Example 6

[0027] The first step is to clean the annealing device. Prepare a quartz tube with a diameter of 15 mm, with one end closed and the other end open. Use deionized water (resistivity of about 18 MΩ·cm), acetone, aqua regia (a mixture of hydrochloric acid and nitric acid with a volume ratio of 3:1), and deionized water (resistivity of about 18 MΩ·cm) to ultrasonically clean the quartz tube for 0.5 hours; finally, place it in a vacuum drying oven and bake it at 120°C for 6 hours. The second step is to treat the crystal to be annealed. Polishing Fe 2+ : ZnSe wafer, wafer thickness 3mm. Use 2500#, 5000# and 7000# sandpaper to polish the wafer surface for 10 minutes in turn; then polish it with a suspension of aluminum oxide with a particle size of 0.2μm and water for 8 minutes, and then polish it with a suspension of aluminum oxide with a particle size of 30nm and water for 5 minutes, and finally use deionized water ultrasound for 10 minutes and dry it in a vacuum drying oven. The third step is crystal annealing. The treated Fe 2+ : The ZnSe wafer is fixed vertically on the quartz support and placed at one end of the round bottom of the quartz tube cleaned in the first step. Then high-purity metal Zn particles are loaded into the other end of the quartz tube and the quartz tube is evacuated. When the vacuum degree reaches 10 -3 When the temperature is below Pa, the quartz tube mouth is sealed with hydrogen-oxygen flame. The fourth step is to place the vacuumized quartz tube in a five-stage horizontal annealing furnace and set the annealing parameters: Fe is placed in the quartz tube. 2+ One end of the ZnSe wafer is in the low temperature zone, with a temperature of 1000°C and a temperature gradient of 50°C, while the end with high-purity Zn particles is in the high temperature constant temperature zone, where the temperature is higher than that of the Fe 2+ The ZnSe wafer is placed at a temperature of 80°C and the annealing time is 72 hours. After the annealing is completed, the temperature is lowered to room temperature at a rate of 10°C / h. In the fifth step, the annealed wafer is taken out, and the slurry prepared by the aluminum oxide and water with a particle size of 0.2μm and 30nm in the second step is used to polish the surface of the annealed wafer for 5 minutes, and then ultrasonically treated with deionized water for 10 minutes, and the wafer is dried in a vacuum drying oven to obtain the modified high optical quality Fe 2+ :ZnSe crystal.

[0028] Example 7

[0029] The first step is to clean the annealing device. Prepare a quartz tube with a diameter of 20 mm, with a closed round bottom at one end and an open end. Use deionized water (resistivity of about 18 MΩ·cm), acetone, aqua regia (a mixture of hydrochloric acid and nitric acid with a volume ratio of 3:1), and deionized water (resistivity of about 18 MΩ·cm) to ultrasonically clean the quartz tube for 0.5 hours; finally, place it in a vacuum drying oven and bake it at 120°C for 5 hours. The second step is to treat the crystal to be annealed. Polishing Fe 2+: ZnSe wafer, wafer thickness 1mm. Use 2500#, 5000# and 7000# sandpaper to polish the wafer surface for 3 minutes in turn; then polish it with a suspension of aluminum oxide with a particle size of 0.2μm and water for 6 minutes, and then polish it with a suspension of aluminum oxide with a particle size of 30nm and water for 5 minutes, and finally use deionized water ultrasound for 5 minutes and dry it in a vacuum drying oven. The third step is crystal annealing. The treated Fe 2+ : The ZnSe wafer is fixed vertically on the quartz support and placed at one end of the round bottom of the quartz tube cleaned in the first step. Then high-purity metal Zn particles are loaded into the other end of the quartz tube and the quartz tube is evacuated. When the vacuum degree reaches 10 -3 When the temperature is below Pa, the quartz tube mouth is sealed with hydrogen-oxygen flame. The fourth step is to place the vacuumized quartz tube in a five-stage horizontal annealing furnace and set the annealing parameters: Fe is placed in the quartz tube. 2+ One end of the ZnSe wafer is in the low temperature zone, with a temperature of 900°C and a temperature gradient of 10°C, while the end with high-purity Zn particles is in the high temperature constant temperature zone, where the temperature is higher than that of the Fe 2+ The ZnSe wafer is placed at a temperature of 30°C and annealed for 24 hours. After annealing, the temperature is lowered to room temperature at a rate of 5°C / h. In the fifth step, the annealed wafer is taken out, and the slurry prepared by alumina with a particle size of 0.2μm and 30nm and water in the second step is used to polish the surface of the annealed wafer for 3 minutes, and then ultrasonically treated with deionized water for 5 minutes. The wafer is dried in a vacuum drying oven to obtain the modified high optical quality Fe 2+ :ZnSe crystal.

[0030] Example 8

[0031] The first step is to clean the annealing device. Prepare a quartz tube with a diameter of 20 mm, with a closed round bottom at one end and an open end. Use deionized water (resistivity of about 18 MΩ·cm), acetone, aqua regia (a mixture of hydrochloric acid and nitric acid with a volume ratio of 3:1), and deionized water (resistivity of about 18 MΩ·cm) to ultrasonically clean the quartz tube for 0.5 hours; finally, place it in a vacuum drying oven and bake it at 120°C for 6 hours. The second step is to treat the crystal to be annealed. Polishing Fe 2+ : ZnSe wafer, wafer thickness 2mm. Use 2500#, 5000# and 7000# sandpaper to polish the wafer surface for 6 minutes in turn; then polish it with a suspension of aluminum oxide with a particle size of 0.2μm and water for 7 minutes, and then polish it with a suspension of aluminum oxide with a particle size of 30nm and water for 5 minutes, and finally use deionized water ultrasound for 8 minutes and dry it in a vacuum drying oven. The third step is crystal annealing. The treated Fe 2+ : The ZnSe wafer is fixed vertically on the quartz support and placed at one end of the round bottom of the quartz tube cleaned in the first step. Then high-purity metal Zn particles are loaded into the other end of the quartz tube and the quartz tube is evacuated. When the vacuum degree reaches 10-3 When the temperature is below Pa, the quartz tube mouth is sealed with hydrogen-oxygen flame. The fourth step is to place the vacuumized quartz tube in a five-stage horizontal annealing furnace and set the annealing parameters: Fe is placed in the quartz tube. 2+ One end of the ZnSe wafer is in the low temperature zone, with a temperature of 950°C and a temperature gradient of 30°C, while the end with high-purity Zn particles is in the high temperature constant temperature zone, where the temperature is higher than that of the Fe 2+ The ZnSe wafer is placed at a temperature of 50°C and annealed for 48 hours. After annealing, the temperature is lowered to room temperature at a rate of 8°C / h. In the fifth step, the annealed wafer is taken out, and the slurry prepared by alumina with a particle size of 0.2μm and 30nm and water in the second step is used to polish the surface of the annealed wafer for 4 minutes, and then ultrasonically treated with deionized water for 8 minutes. The wafer is dried in a vacuum drying oven to obtain the modified high optical quality Fe 2+ :ZnSe crystal.

[0032] Example 9

[0033] The first step is to clean the annealing device. Prepare a quartz tube with a diameter of 20 mm, with a closed round bottom at one end and an open end. Use deionized water (resistivity of about 18 MΩ·cm), acetone, aqua regia (a mixture of hydrochloric acid and nitric acid with a volume ratio of 3:1), and deionized water (resistivity of about 18 MΩ·cm) to ultrasonically clean the quartz tube for 0.5 hours; finally, place it in a vacuum drying oven and bake it at 120°C for 6 hours. The second step is to treat the crystal to be annealed. Polishing Fe 2+ : ZnSe wafer, wafer thickness 3mm. Use 2500#, 5000# and 7000# sandpaper to polish the wafer surface for 10 minutes in turn; then polish it with a suspension of aluminum oxide with a particle size of 0.2μm and water for 8 minutes, and then polish it with a suspension of aluminum oxide with a particle size of 30nm and water for 5 minutes, and finally use deionized water ultrasound for 10 minutes and dry it in a vacuum drying oven. The third step is crystal annealing. The treated Fe 2+ : The ZnSe wafer is fixed vertically on the quartz support and placed at one end of the round bottom of the quartz tube cleaned in the first step. Then high-purity metal Zn particles are loaded into the other end of the quartz tube and the quartz tube is evacuated. When the vacuum degree reaches 10 -3 When the temperature is below Pa, the quartz tube mouth is sealed with hydrogen-oxygen flame. The fourth step is to place the vacuumized quartz tube in a five-stage horizontal annealing furnace and set the annealing parameters: Fe is placed in the quartz tube. 2+ One end of the ZnSe wafer is in the low temperature zone, with a temperature of 1000°C and a temperature gradient of 50°C, while the end with high-purity Zn particles is in the high temperature constant temperature zone, where the temperature is higher than that of the Fe 2+The ZnSe wafer is placed at a temperature of 80°C and the annealing time is 72 hours. After the annealing is completed, the temperature is lowered to room temperature at a rate of 10°C / h. In the fifth step, the annealed wafer is taken out, and the slurry prepared by the aluminum oxide and water with a particle size of 0.2μm and 30nm in the second step is used to polish the surface of the annealed wafer for 5 minutes, and then ultrasonically treated with deionized water for 10 minutes, and the wafer is dried in a vacuum drying oven to obtain the modified high optical quality Fe 2+ :ZnSe crystal.

[0034] The above example is specifically described in conjunction with the accompanying drawings, but the invention is not limited to the above implementation scheme. If ordinary personnel in the field make improvements or other forms to the invention without departing from the principle of the present invention, they all fall within the scope of the present invention.

Claims

1. A zinc selenide doped with iron (Fe 2+ :ZnSe) single crystal annealing modification method, characterized in that The following steps are involved: The first step is to clean the annealing tube. First, prepare a quartz tube with a diameter of 10 to 20 mm, with one end closed and the other end open; then, use deionized water (resistivity of about 18MΩ·cm), acetone, aqua regia (a mixture of hydrochloric acid and nitric acid with a volume ratio of 3:1), and deionized water (resistivity of about 18MΩ·cm) to ultrasonically clean the quartz tube for 0.5 hours; finally, place it in a vacuum drying oven and bake it at 120°C for 5 to 6 hours. The second step is to polish Fe 2+ : ZnSe wafer, wafer thickness 1-3mm. Use 2500#, 5000# and 7000# sandpaper to polish the wafer surface for 3-10 minutes; then polish with a suspension of 0.2μm aluminum oxide and water for 6-8 minutes, and then polish with a suspension of 30nm aluminum oxide and water for 5 minutes; finally, use deionized water for ultrasonic treatment for 5-10 minutes and dry in a vacuum drying oven. The third step is to treat the Fe 2+ : The ZnSe wafer is fixed vertically on the quartz support and placed at one end of the round bottom of the quartz tube cleaned in the first step. Then high-purity metal Zn particles are loaded into the other end of the quartz tube and the quartz tube is evacuated. When the vacuum degree reaches 10 -3 When the pressure is below Pa, use hydrogen-oxygen flame to seal the quartz tube mouth. The fourth step is to place the quartz tube that has been evacuated in the third step in a five-stage horizontal annealing furnace and set the annealing parameters: Fe is placed in the quartz tube. 2+ One end of the ZnSe wafer is in the low temperature zone, with a temperature of 900-1000°C and a temperature gradient of 10-50°C, while the end with high-purity Zn particles is in the high temperature constant temperature zone, where the temperature is higher than that of the Fe 2+ The temperature of the ZnSe wafer is 30-80°C, and the annealing time is 24-72 hours; after the annealing is completed, the temperature is lowered to room temperature at a rate of 5-10°C / h. In the fifth step, the wafer annealed in the fourth step is taken out, and the annealed wafer surface is polished for 3 to 5 minutes using the suspension prepared by alumina with a particle size of 0.2 μm and 30 nm and water in the second step, and then ultrasonicated with deionized water for 5 to 10 minutes, and the wafer is dried in a vacuum drying oven to obtain the modified high optical quality Fe 2+ :ZnSe crystal.

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