Method for regulating and controlling ZnSe small-grain-size transparent material through AlMg doping in CVD preparation process and application of ZnSe small-grain-size transparent material

Abstract

The invention belongs to the technical field of semiconductor material preparation, and discloses a method for regulating and controlling a ZnSe small-grain-size transparent material through AlMg doping in the CVD preparation process and application of the method, and the method comprises the steps that S1, in the process of preparing a ZnSe matrix through CVD, an Al doping agent and an Mg doping agent are synchronously introduced for co-doping, and a co-doped ZnSe precursor is obtained; s2, the co-doped ZnSe precursor is sequentially subjected to two-step sintering treatment and hot isostatic pressing treatment, and the ZnSe small-grain-size transparent material is prepared. According to the invention, the problems that gt is easily formed by traditional ZnSe; and the final grain size is stabilized at 20 + / -10 [mu] m, is reduced by 74% compared with an undoped sample (150 + / -50 [mu] m) and is reduced by 60% compared with an Al single-doped sample (50 + / -10 [mu] m), and actual application and operation are facilitated.

Description

A method for controlling the small grain size of ZnSe transparent materials during CVD preparation via AlMg doping and its application. Technical Field

[0001] This invention relates to the field of semiconductor material preparation technology, and in particular to a method for controlling the small grain size of ZnSe transparent material through AlMg doping during CVD preparation and its application. Background Technology

[0002] ZnSe, as a typical group II-VI wide bandgap semiconductor material, is one of the core candidate materials in the fields of infrared optics and laser technology due to its high transmittance, low refractive index dispersion, and excellent photoelectric response characteristics in the 0.6-20μm wavelength range.

[0003] In practical applications, existing equipment typically uses methods like vapor deposition and hot-pressing sintering to prepare ZnSe, which easily leads to the formation of micron-sized coarse grains exceeding 100 μm. These large grains result in:

[0004] Insufficient optical transmittance: The small number of grain boundaries and the large grain boundary spacing amplify the scattering effect of incident light at the grain boundaries, causing the transmittance of ZnSe in the visible-infrared band to decrease by more than 15%, making it difficult to meet the transmittance requirements of high-precision infrared optical windows; the grain boundary bonding force of coarse-grained materials is weak, and the Vickers hardness is generally lower than 80HV, making them prone to cracking and chipping under device assembly, vibration, and other conditions; at the same time, the thermal conductivity is lower than 18W / m・K, and heat is easily accumulated under high-power laser irradiation, causing thermal deformation or even damage to the material, which is not conducive to practical applications and operations. Summary of the Invention

[0005] One objective of this invention is to provide a method for controlling the small grain size of ZnSe transparent materials through AlMg doping during CVD preparation, and its application.

[0006] To achieve the above objectives, the technical solution adopted in this invention is as follows: a method for controlling the small grain size of ZnSe transparent materials through AlMg doping during CVD preparation and its application, comprising the following steps:

[0007] S1: In the process of CVD preparation of ZnSe matrix, Al dopant and Mg dopant are introduced through trimethylaluminum and dimethylmagnesium to co-dopide, thus obtaining co-doped ZnSe;

[0008] S2: The co-doped ZnSe is subjected to hot isostatic pressing to obtain a transparent ZnSe material with small grain size.

[0009] Preferably, the proportion of ZnSe matrix in S1 is 98.5-99.7%, the doping amount of Al element is 0.1-0.8%, the doping amount of Mg element is 0.2-1.5%, and the molar ratio of Al element to Mg element is 1:1.5 to 1:3.

[0010] Preferably, in S1, the Al dopant is introduced in the form of triethylaluminum and the Mg dopant is introduced in the form of diethylmagnesium.

[0011] Preferably, the conditions for hot isostatic pressing in S2 are: 450°C for 1 hour in an Ar atmosphere of 200 MPa.

[0012] Preferably, the material has a grain size of 20μm±10μm, a transmittance of ≥73.8% in the 10μm infrared band, and a Vickers hardness of ≥135.6HV.

[0013] Preferably, the ZnSe small-grain-size transparent material is used in the fabrication of infrared optical windows or high-damage-threshold laser devices.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] (1) This invention solves the problem that traditional ZnSe easily forms coarse grains >100μm, and the final grain size is stabilized at 20±10μm, which is 74% smaller than the undoped sample (150±50μm) and 60% smaller than the Al single-doped sample (50±10μm);

[0016] Due to grain refinement, the impact of grain boundary scattering on the infrared band is significantly reduced. The transmittance of the material in the 10μm infrared band reaches 73.8%, an improvement of 5.6 percentage points compared to the undoped sample. The Vickers hardness increases to 135.6 HV, an improvement of 72.7% compared to the undoped sample, while the thermal conductivity increases to over 22 W / m·K. This solves the problems of insufficient mechanical strength and low thermal conductivity of traditional ZnSe, making it suitable for high-power device applications. It avoids the defect of a 40% decrease in carrier mobility caused by existing Bi doping schemes. The Al / Mg doping of this invention does not introduce carrier trap defects, and the carrier mobility of the material remains at the intrinsic level of ZnSe (>100 cm² / V·s), which can meet the electrical performance requirements of optoelectronic devices such as laser devices.

[0017] (2) The temperature range of the two-step sintering process of this invention is lower than that of traditional hot pressing sintering (the temperature of traditional hot pressing sintering is mostly >800℃), and the energy consumption is reduced by more than 40% compared with the traditional method; and the CVD doping and subsequent processing flow are smoothly connected, without the need to add additional complex equipment, which is suitable for large-scale production.

[0018] By controlling the Al / Mg molar ratio (1:1.5 to 1:3), atomic-level control of grain size can be achieved, and the grain size fluctuation of the material can be controlled within ±10μm. The laser damage threshold of the obtained material is >5J / cm²@1064nm. In addition to being adapted to infrared optical windows, it can also be extended to the fabrication of high damage threshold laser devices, filling the application gap of traditional ZnSe in the field of high-power optoelectronics. Attached Figure Description

[0019] Figure 1 is a schematic diagram of the overall structure of the present invention. Detailed Implementation

[0020] The present invention will now be further described in conjunction with specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0021] In the description of this invention, it should be noted that directional terms such as "center," "lateral," "longitudinal," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise" indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific protection scope of this invention.

[0022] It should be noted that the terms "first" and "second" in the specification and claims of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0023] One preferred embodiment of the present invention, as shown in Figure 1, discloses a method for controlling the small grain size of ZnSe transparent materials during CVD preparation and its application, comprising the following steps:

[0024] S1: In the process of CVD preparation of ZnSe matrix, Al dopant and Mg dopant are introduced through trimethylaluminum and dimethylmagnesium to co-dopide, thus obtaining co-doped ZnSe;

[0025] S2: Hot isostatic pressing is performed on co-doped ZnSe to obtain transparent ZnSe with small grain size.

[0026] The ZnSe matrix in S1 accounts for 98.5-99.7%, the Al doping amount is 0.1-0.8%, the Mg doping amount is 0.2-1.5%, and the molar ratio of Al to Mg is 1:1.5 to 1:3.

[0027] In S1, the Al dopant is introduced in the form of triethylaluminum, and the Mg dopant is introduced in the form of diethylmagnesium.

[0028] The conditions for hot isostatic pressing in S2 are: 450℃ for 1 hour in an Ar atmosphere of 200MPa.

[0029] The material has a grain size of 20μm±10μm, a transmittance of ≥73.8% in the 10μm infrared band, and a Vickers hardness of ≥135.6HV.

[0030] Applications of ZnSe small-grain-size transparent materials in the fabrication of infrared optical windows or high-damage-threshold laser devices.

[0031] Working principle:

[0032] In the CVD preparation of the ZnSe matrix, Al replaces Zn²⁺ in the ZnSe lattice in the form of Al³⁺, inducing cation vacancy defects. These defects lower the Gibbs free energy barrier ΔG* for ZnSe nuclei formation, allowing for mass nucleation at lower supersaturation levels and directly increasing the number of initial nuclei. When Mg is introduced in the form of MgSe, it segregates at ZnSe grain boundaries, forming MgSe₂ nanophases with a size of 2-5 nm. On one hand, these nanophases can adhere to the surface of the initial nuclei, enhancing their structural stability and preventing growth due to spontaneous merging. On the other hand, these dispersed nanophases act as "grain boundary pinning points," increasing the diffusion resistance at grain boundaries and kinetically inhibiting subsequent grain growth.

[0033] The synergistic effect of dual doping: Al doping increases the initial nucleus density and Mg doping inhibits nucleus growth, resulting in a 300% increase in the nucleus density of ZnSe compared to the undoped sample. Combined with a two-step sintering process (the first stage at 650-700℃ ensures sufficient nucleus formation, and the second stage at 550-600℃ matches the pinning effect of doping), grain coarsening is further avoided. The subsequent hot isostatic pressing at 450℃ in a 200MPa Ar atmosphere can eliminate internal pores in the material, ensuring its transparency without affecting the grain size.

[0034] The basic principles, main features, and advantages of this invention have been described above. Those skilled in the art should understand that this invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made without departing from the spirit and scope of the invention, and all such changes and modifications fall within the scope of the invention as claimed. The scope of protection claimed by this invention is defined by the appended claims and their equivalents.

Claims

1. A method for controlling the small grain size of ZnSe transparent materials during CVD preparation via AlMg doping, characterized in that, Includes the following steps: S1: During the CVD preparation of ZnSe matrix, Al dopant and Mg dopant are introduced through trimethylaluminum and dimethylmagnesium to co-dopide, resulting in co-doped ZnSe; S2: The co-doped ZnSe is subjected to hot isostatic pressing to obtain a transparent ZnSe material with small grain size.

2. The method for controlling the small grain size of ZnSe transparent material by AlMg doping during CVD preparation as described in claim 1, characterized in that: The ZnSe matrix in S1 accounts for 98.5-99.7%, the Al doping amount is 0.1-0.8%, the Mg doping amount is 0.2-1.5%, and the molar ratio of Al to Mg is 1:1.5 to 1:

3.

3. The method for controlling the small grain size of ZnSe transparent material by AlMg doping during CVD preparation as described in claim 1, characterized in that: In S1, the Al dopant is introduced in the form of triethylaluminum, and the Mg dopant is introduced in the form of diethylmagnesium.

4. The method for controlling the small grain size of ZnSe transparent material by AlMg doping during CVD preparation as described in claim 1, characterized in that: The conditions for hot isostatic pressing in S2 are: 450℃ for 1 hour in an Ar atmosphere of 200MPa.

5. The ZnSe small-grain-size transparent material prepared by the method according to any one of claims 1-4, characterized in that: The material has a grain size of 20μm±10μm, a transmittance of ≥73.8% in the 10μm infrared band, and a Vickers hardness of ≥135.6HV.

6. The method for controlling the small grain size of ZnSe transparent material by AlMg doping during CVD preparation as described in claim 5, and its application, characterized in that: Application of the ZnSe small-grain-size transparent material in the fabrication of infrared optical windows or high-damage-threshold laser devices.

Images