A method for preparing an antimony-doped cadmium telluride target

Abstract

The application belongs to the field of material preparation, and discloses a preparation method of antimony-doped cadmium telluride target material, which comprises the following steps: (1) uniformly mixing CdTe powder and Sb2Te3 powder, wherein the proportion of Sb2Te3 powder is 0.5-10 wt%; (2) performing heating reaction on the uniformly mixed powder to obtain the antimony-doped cadmium telluride target material; the heating reaction is specifically as follows: stage one: under vacuum condition, heating to 300-400 DEG C, and keeping warm for 30-50 min; stage two: under vacuum condition, heating to 550-600 DEG C, and keeping warm for 60-90 min, and after heating to the highest temperature, the pressure is increased to 80-90 Mpa, and the pressure is kept until the keeping warm time ends. The cadmium telluride doped target material is prepared by vacuum hot-pressing sintering, the process flow is short, the operation is simple, the oxygen content of the obtained cadmium telluride doped target material is low, and the target material has high relative density.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of material preparation and relates to a preparation method of antimony-doped cadmium telluride target material. BACKGROUND

[0002] The highest conversion efficiency of CdTe thin film battery is up to 22.1%, but it is still lower than the theoretical efficiency. The most effective strategy to improve the battery efficiency is to improve the open-circuit voltage Voc and short-circuit current Jsc of the battery. For the CdTe thin film battery, the key to improving the battery efficiency lies in increasing the carrier concentration of the p-CdTe layer and prolonging the carrier lifetime by doping with external elements. The doping elements can be group I and V elements, such as group I elements Cu and group V elements N, P, As, Sb and Bi.

[0003] The patent document with the publication number CN102142481B discloses a method for P-type doping of cadmium telluride, comprising the following steps: providing a first component comprising cadmium telluride CdTe containing an interface region; and subjecting the CdTe to a functionalization treatment to obtain p-type doped CdTe, the functionalization treatment comprising heat treatment of at least a portion of the interface region in the presence of a first material comprising a p-type dopant and a second material comprising a halogen, the p-type dopant comprising antimony, and the first material further comprising at least one of ethylenediamine EDA, a dilute solution of bromine in methanol, a mixture of nitric acid and phosphoric acid and combinations thereof. However, the process and operation are relatively complex, and no process measures are considered to reduce the oxygen content of the target material and improve the performance of the target material such as the relative density during the preparation process. SUMMARY

[0004] The application aims to provide a preparation method of antimony-doped cadmium telluride target material, which has a short process flow and is easy to operate.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the application is:

[0006] A preparation method of antimony-doped cadmium telluride target material, comprising the following steps:

[0007] (1) uniformly mixing CdTe powder and Sb2Te3 powder, wherein the proportion of Sb2Te3 powder is 0.5-10wt%;

[0008] (2) heating and reacting the uniformly mixed powder to obtain the antimony-doped cadmium telluride target material;

[0009] The heating and reaction is specifically:

[0010] Stage one: under vacuum condition, heating to 300-400℃ and keeping the temperature for 30-50min;

[0011] Second stage: under vacuum condition, temperature is raised to 550-600 DEG C, and temperature is kept for 60-90 min, and after temperature is raised to the highest temperature, pressure is added to 80-90 Mpa, and pressure is kept until the end of temperature keeping time.

[0012] Because the melting point of CdTe powder and Sb2Te3 powder is different by 400 DEG C, in order to improve the activity of the powder and reduce the sintering temperature in the subsequent process, further, in step (1), -325 mesh CdTe powder and -325 mesh Sb2Te3 powder are used.

[0013] Further, CdTe and Sb2Te3 are broken in a vacuum environment to obtain CdTe powder and Sb2Te3 powder, and the oxygen content can be reduced.

[0014] Further, in step (1), the CdTe powder and Sb2Te3 powder are mixed uniformly under vacuum condition, and the oxygen content can be reduced.

[0015] Further, in step (2), the first stage: the temperature is raised to 300-400 DEG C at a temperature raising rate of 8-12 DEG C / min, and temperature is kept for 30-50 min. In this stage, pre-sintering can be achieved, and some volatile substances and moisture can be removed to ensure the densification of the target material in the subsequent process.

[0016] Further, in step (2), the second stage: the temperature is raised to 550-600 DEG C at a temperature raising rate of 8-12 DEG C / min, and temperature is kept for 6-90 min, and after the temperature is raised to the highest temperature, pressure is added to 80-90 Mpa, and pressure is kept until the end of temperature keeping time.

[0017] Further, in step (2), the second stage: within 20 min after the temperature is raised to the highest temperature, pressure is added to 80-90 Mpa. After the powder is fully expanded, pressure is added in this stage, and the target material is not easy to crack.

[0018] Further, in step (2), the powder mixed uniformly in step (1) is loaded into a mold and placed in a vacuum hot pressing furnace for heating reaction.

[0019] Further, in step (2), the vacuum condition in the first stage and the second stage during the reaction process is that the vacuum degree is not greater than 10 pa.

[0020] Further, in step (2), after the temperature keeping in the second stage ends, cooling is further included, and the cooling mode is furnace cooling.

[0021] Compared with the prior art, the beneficial effects of the present application are:

[0022] The application adopts vacuum hot-pressing sintering to prepare the cadmium telluride doped target material, and has the advantages of short process flow, simple operation, low oxygen content of the cadmium telluride doped target material, and high relative density of the target material.

[0023] The preferred scheme of the application breaks the cadmium telluride and the antimony telluride in a vacuum environment, and then performs vacuum hot-pressing, so as to achieve the purpose of antimony doping and further reduce the oxygen content. The intermediate temperature is kept for a period of time, and vacuum exhaust is performed, so as to further achieve the purpose of improving the density of the target material. DETAILED DESCRIPTION

[0024] In order to facilitate the understanding of the application, the application will be described more fully below with reference to the preferred embodiments of the description, but the scope of protection of the application is not limited to the following specific embodiments.

[0025] Unless otherwise defined, all the professional terms used below have the same meaning as understood by those skilled in the art. The professional terms used in the text are only for the purpose of describing the specific embodiments and are not intended to limit the scope of protection of the application.

[0026] Embodiment 1

[0027] The embodiment discloses a preparation method of an antimony-doped cadmium telluride target material, comprising the following steps:

[0028] (1) CdTe and Sb2Te3 are broken in a vacuum environment, and are sieved to 325 meshes respectively, so as to obtain CdTe powder and Sb2Te3 powder.

[0029] (2) The CdTe powder and the Sb2Te3 powder are uniformly mixed under vacuum conditions, and the proportion of the Sb2Te3 powder is 10wt%.

[0030] (3) The uniformly mixed powder is loaded into a mold and placed into a vacuum hot-pressing furnace. The temperature is raised to 400 DEG C at 9 DEG C / min, and kept for 50 min; then the temperature is continuously raised to 550 DEG C at 9 DEG C / min, and kept for 90 min; the pressure is increased to 80 Mpa within 20 min after the temperature is raised to the highest temperature, and the pressure is kept until the temperature is lowered.

[0031] (4) The furnace is cooled to room temperature, the mold is demolded, and the antimony-doped cadmium telluride target material is obtained through mechanical processing.

[0032] Embodiment 2

[0033] The embodiment discloses a preparation method of an antimony-doped cadmium telluride target material, comprising the following steps:

[0034] (1) CdTe and Sb2Te3 are broken in a vacuum environment, and are sieved to 325 meshes respectively, so as to obtain CdTe powder and Sb2Te3 powder.

[0035] (2) The CdTe powder and the Sb2Te3 powder are mixed uniformly under vacuum condition, and the proportion of the Sb2Te3 powder is 0.5wt%.

[0036] (3) The uniformly mixed powder is loaded into a mold and placed into a vacuum hot pressing furnace. The temperature is raised to 300 DEG C at a rate of 12 DEG C / min, and then the temperature is raised to 600 DEG C at a rate of 12 DEG C / min after 40 min of heat preservation; in this stage, the pressure is increased to 85 MPa within 20 min after the temperature is raised to the highest temperature, and the pressure is kept until the temperature is lowered.

[0037] (4) The furnace is cooled to room temperature, the mold is demolded, and the antimony-doped cadmium telluride target material is obtained after mechanical processing.

[0038] Example 3

[0039] The embodiment discloses a preparation method of an antimony-doped cadmium telluride target material, which comprises the following steps:

[0040] (1) CdTe and Sb2Te3 are crushed under vacuum environment, and are sieved to 325 meshes respectively to obtain CdTe powder and Sb2Te3 powder.

[0041] (2) The CdTe powder and the Sb2Te3 powder are mixed uniformly under vacuum condition, and the proportion of the Sb2Te3 powder is 0.5wt%.

[0042] (3) The uniformly mixed powder is loaded into a mold and placed into a vacuum hot pressing furnace. The temperature is raised to 300 DEG C at a rate of 12 DEG C / min, and then the temperature is raised to 600 DEG C at a rate of 12 DEG C / min after 40 min of heat preservation; in this stage, the pressure is increased to 85 MPa within 20 min after the temperature is raised to the highest temperature, and the pressure is kept until the temperature is lowered.

[0043] (4) The furnace is cooled to room temperature, the mold is demolded, and the antimony-doped cadmium telluride target material is obtained after mechanical processing.

[0044] Comparative Example 1

[0045] The comparative example is basically the same as the example 3, and the difference lies in that:

[0046] In the step (1) of the comparative example, CdTe and Sb2Te3 are not crushed under vacuum environment, and are sieved to 325 meshes respectively to obtain CdTe powder and Sb2Te3 powder.

[0047] Comparative Example 2

[0048] The comparative example is basically the same as the example 3, and the difference lies in that:

[0049] In the step (2) of the comparative example, the CdTe powder and the Sb2Te3 powder are mixed uniformly under vacuum condition, and the proportion of the Sb2Te3 powder is 15wt%.

[0050] Comparative Example 3

[0051] This comparative example is basically the same as Example 3, except that:

[0052] In step (1) of this comparative example, CdTe and Sb2Te3 were crushed in a vacuum environment and sieved to 100 mesh, respectively, to obtain CdTe powder and Sb2Te3 powder.

[0053] The antimony-doped cadmium telluride targets obtained in Examples 1-3 and Comparative Examples 1 / 2 were detected, and the test data are shown in Table 1.

[0054] Table 1 Test data

[0055]

[0056] It can be seen that the antimony-doped cadmium telluride target product prepared by the present application has stable quality, low oxygen content, and high target relative density.

[0057] The above is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the scope of the present application.

Claims

1. A method for preparing an antimony-doped cadmium telluride target, characterized in that: The following steps are involved: (1) CdTe and Sb2Te3 were crushed separately under vacuum to obtain CdTe powder and Sb2Te3 powder. -325 mesh CdTe powder and -325 mesh Sb2Te3 powder were used. The CdTe powder and Sb2Te3 powder were mixed evenly under vacuum conditions, wherein the Sb2Te3 powder accounted for 0.5~10wt%; (2) heating the uniformly mixed powder to react and obtain an antimony-doped cadmium telluride target; The heating reaction is specifically: Stage 1: Under vacuum conditions, heat to 300-400°C and keep warm for 30-50 minutes; The second stage: under vacuum conditions, the temperature is raised to 550~600℃ and kept warm for 60~90min. In this stage, after the temperature is raised to the highest temperature, the pressure is increased to 80~90Mpa and the pressure is maintained until the end of the holding time.

2. The method for preparing an antimony-doped cadmium telluride target according to claim 1, wherein: In step (2), the first stage: heating to 300-400°C at a heating rate of 8-12°C / min, and keeping the temperature for 30-50 min.

3. The method for preparing an antimony-doped cadmium telluride target according to claim 1, wherein: In step (2), the second stage: heating to 550~600℃ at a heating rate of 8~12℃ / min, and keeping warm for 6~90min. In this stage, after heating to the highest temperature, pressurizing to 80~90Mpa is started, and the pressure is maintained until the end of the holding time.

4. The method for preparing an antimony-doped cadmium telluride target according to claim 1 or 3, wherein: In step (2), the second stage: in this stage, the pressure is increased to 80~90Mpa within 20 minutes after the temperature is raised to the highest temperature.

5. The method for preparing an antimony-doped cadmium telluride target according to claim 1, wherein: In step (2), the uniformly mixed powder obtained in step (1) is placed into a mold and placed in a vacuum hot pressing furnace for heating reaction.

6. The method for preparing an antimony-doped cadmium telluride target according to claim 1, wherein: In step (2), during the reaction process, the vacuum conditions in the first and second stages are specifically that the vacuum degree is not greater than 10 Pa.

7. The method for preparing an antimony-doped cadmium telluride target according to claim 1, wherein: In step (2), after the second stage of heat preservation is completed, the temperature is also lowered, and the cooling method is furnace cooling.

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