阅读说明：本技术 提高CdZnTe探测器性能的CdZnTe/GaAs外延膜及制备方法 (CdZnTe/GaAs epitaxial film for improving performance of CdZnTe detector and preparation method thereof ) 是由 万鑫 查钢强 李阳 曹昆 刘雅洁 魏鹤鸣 李颖锐 于 2021-07-27 设计创作，主要内容包括：本发明涉及一种提高CdZnTe探测器性能的CdZnTe/GaAs外延膜及制备方法,基于P型GaAs衬底上生长CdZnTe厚膜并在Te-(2)气氛中进行等温退火。将其制备成Au/CdZnTe/p-GaAs/Au探测器,与退火之前相比,CdZnTe外延膜的电阻率明显提高,探测器对～(241)Am@5.49MeVα粒子响应更加灵敏,能量分辨率提高,并且在退火之后出现了对～(241)Am@59.5KeVγ射线的响应。本发明提供的改性方法包括衬底的预处理、CdZnTe外延膜的生长过程、CdZnTe外延膜的退火过程及辐射探测器的制备。(The invention relates to a CdZnTe/GaAs epitaxial film for improving the performance of a CdZnTe detector and a preparation method thereof, which is based on growing a CdZnTe thick film on a P-type GaAs substrate and growing a CdZnTe thick film on the Te thick film 2 Isothermal annealing is performed in an atmosphere. The prepared CdZnTe epitaxial film has obviously improved resistivity and detector pair compared with that before annealing 241 Am@5.4The 9MeV alpha particle response is more sensitive, the energy resolution is improved, and the annealing is followed by the generation of the pair 241 Am @59.5KeV gamma ray response. The modification method provided by the invention comprises the steps of pretreatment of the substrate, the growth process of the CdZnTe epitaxial film, the annealing process of the CdZnTe epitaxial film and preparation of the radiation detector.)

1. A CdZnTe/GaAs epitaxial film for improving the performance of a CdZnTe detector is characterized in that: growing CdZnTe epitaxial film on GaAs substrate, and then growing CdZnTe epitaxial film on Te₂Annealing at moderate temperature in the atmosphere to obtain the CdZnTe/GaAs epitaxial film.

2. A method for preparing the CdZnTe/GaAs epitaxial film of claim 1, characterized by the steps of:

step 1, pretreatment of a substrate: ultrasonically cleaning a GaAs substrate in acetone, absolute ethyl alcohol and deionized water respectively at room temperature to remove impurities and organic matters on the surface; after cleaning, the substrate is placed in H₂SO₄:H₂O₂:H₂Etching for 20s in the solution with the ratio of O to 1:1, washing with deionized water after etching is finished, and finally blowing and drying with nitrogen gas to be placed in an upper heating table of a near-space sublimation furnace;

step 2, preprocessing the CdZnTe polycrystalline source: polishing an oxide layer on the surface of a polycrystalline source by using sand paper, and then respectively ultrasonically cleaning in acetone, absolute ethyl alcohol and deionized water at room temperature to remove impurities and organic matters on the surface; finally, drying the mixture by using nitrogen and putting the mixture into a lower heating table of a close-space sublimation furnace;

step 3, setting a growth program: the upper heating table and the lower heating table of the near-space sublimation furnace respectively control the temperature of the substrate and the temperature of the polycrystalline source, and the growth of the epitaxial film adopts a two-step method, namely the temperature of the upper heating table is firstly increased to 833K and then is kept for 0.5h, then is reduced to 730K and is kept for 3.5h, the temperature of the lower heating table is always kept at 983K, and the growth time is 4 h;

step 4, growth of the CdZnTe epitaxial film: opening a near-space sublimation furnace, putting the pretreated polycrystalline source and the substrate into the sublimation furnace, starting a mechanical pump and a vent valve, automatically accessing a molecular pump when the vacuum degree of a cavity is lower than 5Pa, pumping the vacuum degree in the cavity to 0.05Pa, running the growth program in the step 3, opening water cooling, cooling the inside of the furnace to room temperature after the program is run, sequentially closing the vent valve, the molecular pump and the water cooling, and taking out the CdZnTe/GaAs epitaxial film;

step 5, annealing the CdZnTe epitaxial film: opening the close-space sublimation furnace, putting an annealing source and the CdZnTe/GaAs epitaxial film into the sublimation furnace, starting a mechanical pump and a vent valve, and operating an annealing program when the vacuum degree of a cavity is lower than 10 Pa; the annealing is constant temperature annealing, and an annealing source is a powdery Te simple substance; the upper heating table and the lower heating table respectively control the temperature of the CdZnTe/GaAs epitaxial film and the annealing source; and opening water cooling, closing the vent valve and the mechanical pump, closing the water cooling after the program operation is finished and the furnace is cooled to room temperature, and preparing the CdZnTe/GaAs epitaxial film.

3. The method of claim 2, wherein: the ultrasonic cleaning is carried out for 20-25 minutes.

4. The method of claim 2, wherein: the area of the GaAs substrate is smaller than that of the polycrystalline source.

5. The method of claim 2, wherein: the purity of the powdery Te simple substance is 7N.

6. A CdZnTe detector using the CdZnTe/GaAs epitaxial film of claim 1, wherein: and a gold electrode layer with the thickness not exceeding 100nm is combined on the epitaxial film of the CdZnTe/GaAs and the substrate surface to form the Au/CdZnTe/p-GaAs/Au detector.

7. A CdZnTe detector using the CdZnTe/GaAs epitaxial film of claim 1, wherein: and putting the CdZnTe/GaAs epitaxial film into an evaporator by adopting a vacuum evaporation method, pumping the vacuum degree to 0.005Pa, and respectively evaporating 80nm gold electrode layers on the epitaxial film and the substrate surface to form the Au/CdZnTe/p-GaAs/Au detector.

8. A method for applying the CdZnTe sensor as claimed in claim 6 or 7, wherein: the Au/CdZnTe/p-GaAs/Au detector is used for detecting the position of the target²⁴¹Am @59.5KeV gamma ray response.

Technical Field

The invention belongs to the technical field of CdZnTe detectors, and relates to a CdZnTe/GaAs epitaxial film for improving the performance of the CdZnTe detector and a preparation method thereof, in particular to a method for improving the detection performance of a CdZnTe semiconductor epitaxial film material.

Background

Cd_1-xZn_xTe (CdZnTe or CZT for short) is a II-VI compound semiconductor with excellent photoelectric property, has the advantages of higher atomic number, larger forbidden bandwidth, higher intrinsic mu tau value, lower electron-hole ionization energy and the like, and is considered as an ideal room-temperature X-ray and gamma-ray detector material. At present, room temperature radiation detectors made of CZT single crystal materials are widely applied to the fields of nuclear medicine, industrial nondestructive testing, aerospace, celestial body physics and the like.

The problems of low efficiency, low ingot utilization rate, incapability of recycling waste materials and the like in the conventional melt growth method are solved well by a close space sublimation method. The CSS method for growing the thin film improves the growth efficiency, but due to mismatch between the thin film and the substrate in the epitaxial heterojunction, a large number of structural defects and electric impurities inevitably exist in the epitaxial film, and a trap energy level is introduced into an energy band. The energy levels generate the action processes of recombination, capture, scattering and the like on the carriers, thereby influencing the transport characteristics such as the service life, the mobility and the like of the carriers and finally influencing the detection performances such as the energy resolution, the charge collection rate and the like of the CZT detector. For room temperature nuclear radiation detector, the key to its high performance is high quality CZT film, which requires higher resistance: (>10¹⁰Ω · cm), a large carrier mobility lifetime product. For obtaining a high-quality CZT film, on one hand, a proper growth process can be explored, and an epitaxial film with few defects can be obtained by controlling the growth process; on the other hand, the epitaxial film can be subjected to annealing modification treatment, so that the defects are further reduced.

The main defects of the CZT film grown by the CSS method are dislocation and point defect, the dislocation comprises interface dislocation and threading dislocation, the integrity of crystal lattice is damaged, and the energy resolution and the resistivity of the detector are reduced; the existence of point defects can also have great influence on the resistivity of the detector, and the method grows the CZT film based on the CSS method and carries out Te on the CZT film₂And (3) modifying by atmosphere annealing, and adjusting the dislocation density and the intrinsic point defect concentration in the film so as to achieve the purpose of improving the photoelectric property of the film.

The CSS method of growing CdZnTe epitaxial films inevitably has point defects and dislocations due to lattice mismatch, which destroy the lattice integrity and reduce the energy resolution and resistivity of the detector.

Disclosure of Invention

Technical problem to be solved

In order to avoid the defects of the prior art, the invention provides a CdZnTe/GaAs epitaxial film for improving the performance of a CdZnTe detector and a preparation method thereof₂And annealing at moderate temperature in the atmosphere, regulating and controlling defects in the epitaxial film, and finally preparing the Au/CdZnTe/p-GaAs/Au detector to achieve the aim of improving the detection performance of the detector.

Technical scheme

A CdZnTe/GaAs epitaxial film for improving the performance of a CdZnTe detector is characterized in that: growing CdZnTe epitaxial film on GaAs substrate, and then growing CdZnTe epitaxial film on Te₂Annealing at moderate temperature in the atmosphere to obtain the CdZnTe/GaAs epitaxial film.

A method for preparing the CdZnTe/GaAs epitaxial film is characterized by comprising the following steps:

step 1, pretreatment of the substrate: ultrasonically cleaning a GaAs substrate in acetone, absolute ethyl alcohol and deionized water respectively at room temperature to remove impurities and organic matters on the surface; after cleaning, the substrate is placed in H₂SO₄:H₂O₂:H₂Etching for 20s in the solution with the ratio of O to 1:1, washing with deionized water after etching is finished, and finally blowing and drying with nitrogen gas to be placed in an upper heating table of a near-space sublimation furnace;

step 2, preprocessing the CdZnTe polycrystalline source: polishing an oxide layer on the surface of a polycrystalline source by using sand paper, and then respectively ultrasonically cleaning in acetone, absolute ethyl alcohol and deionized water at room temperature to remove impurities and organic matters on the surface; finally, drying the mixture by using nitrogen and putting the mixture into a lower heating table of a close-space sublimation furnace;

step 3, setting a growth program: the upper heating table and the lower heating table of the near-space sublimation furnace respectively control the temperature of the substrate and the temperature of the polycrystalline source, and the growth of the epitaxial film adopts a two-step method, namely the temperature of the upper heating table is firstly increased to 833K and then is kept for 0.5h, then is reduced to 730K and is kept for 3.5h, the temperature of the lower heating table is always kept at 983K, and the growth time is 4 h;

step 4, growth of the CdZnTe epitaxial film: opening a near-space sublimation furnace, putting the pretreated polycrystalline source and the substrate into the sublimation furnace, starting a mechanical pump and a vent valve, automatically accessing a molecular pump when the vacuum degree of a cavity is lower than 5Pa, pumping the vacuum degree in the cavity to 0.05Pa, running the growth program in the step 3, opening water cooling, cooling the inside of the furnace to room temperature after the program is run, sequentially closing the vent valve, the molecular pump and the water cooling, and taking out the CdZnTe/GaAs epitaxial film;

step 5, annealing the CdZnTe epitaxial film: opening the close-space sublimation furnace, putting an annealing source and the CdZnTe/GaAs epitaxial film into the sublimation furnace, starting a mechanical pump and a vent valve, and operating an annealing program when the vacuum degree of a cavity is lower than 10 Pa; the annealing is constant temperature annealing, and an annealing source is a powdery Te simple substance; the upper heating table and the lower heating table respectively control the temperature of the CdZnTe/GaAs epitaxial film and the annealing source; and opening water cooling, closing the vent valve and the mechanical pump, closing the water cooling after the program operation is finished and the furnace is cooled to room temperature, and preparing the CdZnTe/GaAs epitaxial film.

The ultrasonic cleaning is carried out for 20-25 minutes

The area of the GaAs substrate is smaller than that of the polycrystalline source.

The purity of the powdery Te simple substance is 7N.

A CdZnTe detector adopting the CdZnTe/GaAs epitaxial film is characterized in that: and a gold electrode layer with the thickness not exceeding 100nm is combined on the epitaxial film of the CdZnTe/GaAs and the substrate surface to form the Au/CdZnTe/p-GaAs/Au detector.

A CdZnTe detector adopting the CdZnTe/GaAs epitaxial film is characterized in that: and putting the CdZnTe/GaAs epitaxial film into an evaporator by adopting a vacuum evaporation method, pumping the vacuum degree to 0.005Pa, and respectively evaporating 80nm gold electrode layers on the epitaxial film and the substrate surface to form the Au/CdZnTe/p-GaAs/Au detector.

An application method of the CdZnTe detector is characterized in that: the Au/CdZnTe/p-GaAs/Au detector is used for detecting the position of the target²⁴¹Am @59.5KeV gamma ray response.

Advantageous effects

The invention provides a CdZnTe/GaAs epitaxial film for improving the performance of a CdZnTe detector and a preparation method thereof₂Isothermal annealing is performed in an atmosphere. The prepared CdZnTe epitaxial film has obviously improved resistivity and detector pair compared with that before annealing²⁴¹Am @5.49MeV alpha particle response is more sensitive, energy resolution is improved, and pair appears after annealing²⁴¹Am @59.5KeV gamma ray response. The modification method provided by the invention comprises the steps of pretreatment of the substrate, the growth process of the CdZnTe epitaxial film, the annealing process of the CdZnTe epitaxial film and preparation of the radiation detector.

Compared with the prior art, the resistivity of the CdZnTe epitaxial film is obviously improved, and the detector pair²⁴¹Am @5.49MeV alpha particle response is more sensitive, energy resolution is improved, and pair appears after annealing²⁴¹Am @59.5KeV gamma ray response.

Drawings

FIG. 1 is an EPD scan of a CdZnTe epitaxial film grown in the as-grown state after annealing according to an embodiment of the present invention and a comparative example.

FIG. 2 is an I-V curve diagram of an Au/CdZnTe/p-GaAs/Au detector formed by annealing a CdZnTe epitaxial film according to an embodiment of the present invention and an Au/CdZnTe/p-GaAs/Au detector formed by annealing a CdZnTe epitaxial film grown in a comparative example.

FIG. 3 shows an embodiment of the present invention in which a CdZnTe epitaxial film is annealed to form an Au/CdZnTe/p-GaAs/Au detector and a growing CdZnTe epitaxial film is used to form an Au/CdZnTe/p-GaAs/Au detector²⁴¹Am @5.49MeV alpha particles by Hecht equation fitting electron mobility life product.

FIG. 4 shows the result of an Au/CdZnTe/p-GaAs/Au detector formed by annealing CdZnTe epitaxial film according to an embodiment of the present invention²⁴¹Am @59.5 full energy peak of KeV gamma rays.

Detailed Description

The invention will now be further described with reference to the following examples and drawings:

example one

In this embodiment, a method for improving the performance of a CdZnTe epitaxial film detector is characterized in that: firstly growing CdZnTe epitaxial film on GaAs substrate, and then growing CdZnTe epitaxial film on Te₂And carrying out isothermal annealing in the atmosphere to finally prepare the Au/CdZnTe/p-GaAs/Au detector. The thickness of the CdZnTe epitaxial film is 280um, and the thickness of the GaAs substrate is 550 um.

In this embodiment, the preparation method of the Au/CdZnTe/p-GaAs/Au detector includes the following steps:

pretreatment of the substrate: cutting a GaAs substrate with the thickness of 550um into 12 multiplied by 12mm²Ultrasonically cleaning the square blocks with the sizes of the square blocks in acetone, absolute ethyl alcohol and deionized water at room temperature for 20 to 25 minutes respectively to remove impurities and organic matters on the surfaces of the square blocks; after cleaning, the substrate is placed in H₂SO₄:H₂O₂:H₂Etching for 20s in the solution with the ratio of O to 1:1, washing with deionized water after etching is finished, and finally blowing and drying with nitrogen gas and placing into a near-space sublimation furnace for later use.

Preprocessing a CdZnTe polycrystalline source: cutting a polycrystalline source having a thickness of 2mm into 15X 15mm²The size of the square is that an oxide layer on the surface of the source is polished by 1000-mesh sand paper, and then the square is respectively placed in acetone, water and the like at room temperature,Ultrasonically cleaning in absolute ethyl alcohol and deionized water for 20 to 25 minutes to remove impurities and organic matters on the surface; and finally, drying by using nitrogen, and putting into a close space sublimation furnace for later use.

Setting of the growth program: the upper heating table and the lower heating table of the near-space sublimation furnace respectively control the temperature of the substrate and the temperature of the polycrystalline source, the growth of the epitaxial film adopts a two-step method, namely the temperature of the upper heating table is firstly increased to 833K and then is kept for 0.5h, then is reduced to 730K and is kept for 3.5h, the temperature of the lower heating table is always kept at 983K, and the growth time is 4 h.

The growth process of the CdZnTe epitaxial film comprises the following steps: opening a near-space sublimation furnace, putting the preprocessed polycrystalline source and the preprocessed substrate into the sublimation furnace, starting a mechanical pump and a vent valve, automatically accessing a molecular pump when the vacuum degree of a cavity is lower than 5Pa, pumping the vacuum degree in the cavity to 0.05Pa, running a growth program, opening water cooling, cooling the inside of the furnace to room temperature after the program is run, sequentially closing the vent valve, the molecular pump and the water cooling, taking out the CdZnTe/GaAs epitaxial film, wherein the thickness of the CdZnTe epitaxial film is 280 um.

Annealing process of CdZnTe epitaxial film: opening a close-space sublimation furnace, putting an annealing source and an epitaxial film into the sublimation furnace, starting a mechanical pump and a vent valve, operating an annealing program when the vacuum degree of a cavity is lower than 10Pa, wherein the annealing is constant-temperature annealing, the annealing source is a powdery Te simple substance, and the purity is 7N; the upper heating table and the lower heating table respectively control the temperature of the epitaxial film and the annealing source, and the temperatures of the upper heating table and the lower heating table are heated to 623K and kept for 10 hours. And opening water cooling, closing the vent valve and the mechanical pump, closing the water cooling after the program operation is completed and the furnace is cooled to room temperature, and taking out the CdZnTe/GaAs epitaxial film.

A radiation detector is formed by combining a gold electrode layer with the thickness of less than or equal to 100nm on an epitaxial film of CdZnTe/GaAs and the surface of a substrate.

A preparation method of a radiation detector comprises the following steps: and putting the CdZnTe/GaAs epitaxial film into an evaporator by adopting a vacuum evaporation method, pumping the vacuum degree to 0.005Pa, and respectively evaporating 80nm gold electrode layers on the epitaxial film and the substrate surface to form the Au/CdZnTe/p-GaAs/Au detector.

Application of radiation detector, namely enabling Au/CdZnTe/p-GaAs/Au detector to be paired²⁴¹Am @59.5KeV gamma ray response.

Compared with the prior art, the invention has the following obvious substantive characteristics and advantages:

compared with the prior art, the resistivity of the CdZnTe epitaxial film is obviously improved, and the detector pair²⁴¹Am @5.49MeV alpha particle response is more sensitive, energy resolution is improved, and pair appears after annealing²⁴¹Am @59.5KeV gamma ray response.

Comparative example:

in the comparison, the Au/CdZnTe/p-GaAs/Au detector is prepared by firstly growing a CdZnTe epitaxial film on a GaAs substrate, then evaporating a gold electrode layer with the thickness of less than or equal to 100nm on the epitaxial film and the substrate surface, and finally preparing the Au/CdZnTe/p-GaAs/Au detector. The thickness of the CdZnTe epitaxial film is 270um, and the thickness of the GaAs substrate is 550 um.

Combining the examples and comparative examples, the present example was conducted by adding Te₂The CdZnTe epitaxial film annealed in the atmosphere is prepared into an Au/CdZnTe/p-GaAs/Au detector and an Au/CdZnTe/p-GaAs/Au detector which is prepared by directly using the CdZnTe epitaxial film in a growing state in a comparative example, and the explanation of the figure obtained by testing by adopting an experimental instrument is as follows:

FIGS. 1 (a) and (b) EPD scans of CdZnTe epitaxial films of the present invention after annealing and comparative examples, respectively, the dislocation etch pit densities of the annealed and as-grown epitaxial films were 2.29X 10⁵And 1.56X 10⁵cm^-2The dislocation density is significantly reduced.

FIG. 2 is an I-V curve diagram of an Au/CdZnTe/p-GaAs/Au detector formed by annealing a CdZnTe epitaxial film according to an embodiment of the present invention and an Au/CdZnTe/p-GaAs/Au detector formed by annealing a CdZnTe epitaxial film grown in a comparative example. The resistivities of the probes made of the annealed and grown epitaxial films were 4.38X 10, respectively⁹Omega cm and 5.47X 10⁸Omega cm, the resistivity of the detector can be obviously improved by annealing treatment.

FIG. 3 shows an Au/CdZnTe/p-GaAs/Au detector and a CdZnTe epitaxial film annealed in accordance with an embodiment of the present inventionThe long CdZnTe epitaxial film is made into an Au/CdZnTe/p-GaAs/Au detector²⁴¹Am @5.49MeV alpha particles by Hecht equation fitting electron mobility life product. The electron mobility lifetime products of the annealed and grown epitaxial films for the detector were 9.30X 10^-4cm²·V^-1And 5.27X 10^-4cm²·V^-1The annealing treatment can obviously improve the electron mobility life product of the detector.

FIG. 4 shows the result of an Au/CdZnTe/p-GaAs/Au detector formed by annealing CdZnTe epitaxial film according to an embodiment of the present invention²⁴¹Am @59.5KeV gamma ray full energy peak, and Au/CdZnTe/p-GaAs/Au detector made of growth state epitaxial film can not be used for detecting²⁴¹Am @59.5KeV gamma rays produce a response.

The embodiment can obviously improve the resistivity of the detector made of the CdZnTe epitaxial film, and the CdZnTe epitaxial film can be used for detecting the CdZnTe epitaxial film²⁴¹Am @5.49MeV alpha particle response is more sensitive, energy resolution is improved, and the method is suitable for²⁴¹Am @59.5KeV gamma rays produce a response.

Example two

This embodiment is substantially the same as the first embodiment, and is characterized in that:

in this embodiment, the annealing process for the CdZnTe epitaxial film is as follows:

and (3) annealing process: opening a close-space sublimation furnace, putting an annealing source and an epitaxial film into the sublimation furnace, starting a mechanical pump and a vent valve, operating an annealing program when the vacuum degree of a cavity is lower than 10Pa, wherein the annealing is constant-temperature annealing, the annealing source is a powdery Te simple substance, and the purity is 7N; the upper heating table and the lower heating table respectively control the temperature of the epitaxial film and the annealing source, and the temperatures of the upper heating table and the lower heating table are heated to 623K and kept warm for 5 hours. And opening water cooling, closing the vent valve and the mechanical pump, closing the water cooling after the program operation is completed and the furnace is cooled to room temperature, and taking out the CdZnTe/GaAs epitaxial film.

The embodiment can slightly improve the resistivity of the detector made of the CdZnTe epitaxial film, and the detector²⁴¹Am @5.49MeV alpha particles are sensitive to response strain, the energy resolution is slightly improved, but the response strain is not good²⁴¹Am @59.5KeV gamma rays produce a response.

EXAMPLE III

This embodiment is substantially the same as the first embodiment, and is characterized in that:

in this embodiment, the annealing process for the CdZnTe epitaxial film is as follows:

and (3) annealing process: opening a close-space sublimation furnace, putting an annealing source and an epitaxial film into the sublimation furnace, starting a mechanical pump and a vent valve, operating an annealing program when the vacuum degree of a cavity is lower than 10Pa, wherein the annealing is constant-temperature annealing, the annealing source is a powdery Te simple substance, and the purity is 7N; the upper and lower heating stages respectively control the temperatures of the epitaxial film and the annealing source, and the temperatures of the upper and lower heating stages are heated to 673K and kept for 10 h. And opening water cooling, closing the vent valve and the mechanical pump, closing the water cooling after the program operation is completed and the furnace is cooled to room temperature, and taking out the CdZnTe/GaAs epitaxial film.

The embodiment can slightly improve the resistivity of the detector made of the CdZnTe epitaxial film, and the detector²⁴¹Am @5.49MeV alpha particles are sensitive to response strain, the energy resolution is slightly improved, but the response strain is not good²⁴¹Am @59.5KeV gamma rays produce a response.

In summary, the above embodiments of the present invention provide a method for improving the performance of an epitaxial film of a CdZnTe detector, which includes growing a CdZnTe epitaxial film on a GaAs substrate, and then growing a CdZnTe epitaxial film on Te₂Isothermal annealing is carried out under different conditions in the atmosphere, and the Au/CdZnTe/p-GaAs/Au detector is finally prepared by 3 steps. The embodiment of the invention can obviously improve the resistivity of the detector made of the CdZnTe epitaxial film, and the detector is suitable for the CdZnTe epitaxial film²⁴¹Am @5.49MeV alpha particle response is more sensitive, energy resolution is improved, and the method is suitable for²⁴¹Am @59.5KeV gamma rays produce a response.

While the embodiments of the present invention have been described with reference to the accompanying drawings, the present invention is not limited to the above embodiments, and various changes, modifications, substitutions and simplifications made according to the spirit and principles of the present invention should be replaced by equivalents thereof, so long as the objects of the present invention are met without departing from the invention of the CdZnTe epitaxial film for detector at Te₂The technical principle of the following annealing belongs to the protection scope of the invention.