Method for improving flowability of semiconductor material powder by high-temperature calcination

Abstract

This invention belongs to the field of semiconductor powder material preparation technology and discloses a method for improving the flowability of semiconductor material powder by high-temperature calcination. The method includes the following steps: (1) the semiconductor material is crushed and loaded into a graphite boat, and then loaded into a horizontal calcination furnace; (2) inert gas is introduced into the horizontal calcination furnace to replace the air, and then inert gas is continuously introduced for protection; (3) the horizontal calcination furnace is heated to a temperature 150-350°C lower than the melting point of the semiconductor material and kept at that temperature for calcination treatment; (4) the material after the heat preservation calcination treatment in step (3) is allowed to cool naturally to room temperature, and then sieved to redisperse the pseudo-agglomerates generated during calcination, thereby obtaining semiconductor powder material with better flowability. The method of this invention has the advantages of simple processing, low equipment requirements, short process cycle, convenient operation, obvious effect, and easy realization of large-scale mass production.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor powder material preparation technology, specifically relating to a method for improving the flowability of semiconductor material powder by high-temperature calcination. Background Technology

[0002] P-type and N-type semiconductors can form a PN junction through close contact at the metallurgical junction interface. The PN junction has the characteristics of reverse breakdown, unidirectional conductivity, current-voltage characteristics, and capacitance characteristics, which makes the PN junction widely used in diodes and photovoltaic power generation.

[0003] Zinc telluride (ZnTe) and other semiconductor materials are widely used in solar cells and infrared materials due to their excellent photoconductivity and fluorescence properties. However, these semiconductor materials require excellent particle size uniformity and flowability for application. Currently, there are few reports, both domestically and internationally, on methods to improve the flowability of semiconductor material powders.

[0004] Patent CN 117182084 A discloses a method for preparing highly homogeneous and highly fluid molybdenum alloy powder. Through a two-step ball milling process combining planetary ball milling and sand milling, the homogenization and refinement of multi-component mixed powders are achieved in a very short time. Subsequent agglomeration and granulation are followed by plasma spheroidization technology for instantaneous micro-sintering of the spherical agglomerates. This method overcomes the shortcomings of traditional vacuum sintering processes, such as long sintering time, easy grain growth, and low fluidity, and can quickly obtain high-quality molybdenum alloy thermal spray powder with a fluidity better than 20s / 50g. However, the above method uses plasma spheroidization technology for powder surface modification, which has the disadvantages of complex processing equipment and high cost. Summary of the Invention

[0005] To address the shortcomings and deficiencies of the existing technologies, the present invention aims to provide a method for improving the flowability of semiconductor material powder through high-temperature calcination. This method employs a temperature below the melting point of the semiconductor material, using an inert gas to protect the calcination process, thereby improving the flowability of the semiconductor powder. It offers advantages such as simple processing, low equipment requirements, short processing cycle, convenient operation, significant results, and ease of large-scale mass production.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A method for improving the flowability of semiconductor material powder by high-temperature calcination includes the following steps:

[0008] (1) After the semiconductor material is crushed, it is loaded into a graphite boat and then into a horizontal calcining furnace;

[0009] (2) Inert gas is introduced into the horizontal calcining furnace to replace the air, and then inert gas is continuously introduced for protection.

[0010] (3) Heat the horizontal calcining furnace to a temperature 150-350°C below the melting point of the semiconductor material and hold it for calcination.

[0011] (4) After the material is heated and calcined in step (3), it is naturally cooled to room temperature, and then screened to redisperse the pseudo-agglomerates generated by calcination, so as to obtain semiconductor powder material with better flowability.

[0012] Further, the semiconductor material mentioned in step (1) is zinc telluride (ZnTe); the temperature of the heat preservation calcination treatment mentioned in step (3) is 800-900℃.

[0013] Furthermore, the pulverization mentioned in step (1) refers to pulverizing to a particle size of 60μm to 400μm.

[0014] Further, the introduction of inert gas to replace air in step (2) refers to the introduction of N2 at a flow rate of 10L / min for 30 minutes; the continuous introduction of inert gas for protection refers to the continuous introduction of N2 at a flow rate of 2L / min for protection.

[0015] Furthermore, the heating rate in step (3) is 5 to 10 °C / min.

[0016] Furthermore, the heat preservation and calcination treatment in step (3) takes 4 to 8 hours.

[0017] Furthermore, the sieving mentioned in step (4) refers to sieving using a 30-mesh sieve.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] This invention involves calcining semiconductor powder materials at a temperature below their melting point, melting the sharp protrusions on the powder particles to make the surface of the semiconductor particles more rounded, thereby improving the flowability of the semiconductor powder material. Compared with existing methods for improving the flowability of powder materials, this invention has the advantages of simple processing, low equipment requirements, large single-batch processing capacity, short process cycle, low cost, convenient operation, significant effect, and ease of large-scale mass production. Attached Figure Description

[0020] Figure 1 This is a diagram showing the state of the material before calcination in Example 1 of the present invention;

[0021] Figure 2 This is a diagram showing the state of the material after calcination in Example 1 of the present invention. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0023] Example 1

[0024] (1) First, zinc telluride (ZnTe) semiconductor material is pulverized to prepare the required particle size (60μm~400μm).

[0025] (2) The pulverized ZnTe semiconductor material powder is loaded into a graphite boat and then into a horizontal calcining furnace.

[0026] (3) Inert gas (N2) is introduced into the horizontal calcining furnace at a flow rate of 10 L / min. After 30 min, the air in the furnace is completely replaced. Then the flow rate is adjusted to 2 L / min and the gas is continuously introduced.

[0027] (4) The horizontal calcining furnace is slowly heated to 800℃ at 10℃ / min, and then held at the temperature for 8 hours for sintering.

[0028] (5) After the heat preservation is completed, the temperature will naturally drop to room temperature, the furnace will be opened, and the material will be discharged.

[0029] (6) The material exiting the furnace is screened through a 30-mesh sieve, which redisperses the pseudo-agglomerates generated during calcination, thus obtaining semiconductor powder materials with better flowability.

[0030] In this embodiment, the state diagrams of zinc telluride powder before calcination in step (1) and after calcination in step (6) are as follows: Figure 1 and Figure 2 As shown in the figure, the results demonstrate that the present invention, through high-temperature calcination, can melt the sharp protrusions on the semiconductor powder particles, resulting in a more rounded surface for the semiconductor material particles.

[0031] Example 2

[0032] (1) First, zinc telluride (ZnTe) semiconductor material is pulverized to prepare the required particle size (60μm~400μm).

[0033] (2) The pulverized ZnTe semiconductor material powder is loaded into a graphite boat and then into a horizontal calcining furnace.

[0034] (3) Inert gas (N2) is introduced into the horizontal calcining furnace at a flow rate of 10 L / min. After 30 min, the air in the furnace is completely replaced. Then the flow rate is adjusted to 2 L / min and the gas is continuously introduced.

[0035] (4) The horizontal calcining furnace is slowly heated to 850°C at 8°C / min, and then held at the temperature for 6 hours for sintering.

[0036] (5) After the heat preservation is completed, the temperature will naturally drop to room temperature, the furnace will be opened, and the material will be discharged.

[0037] (6) The material exiting the furnace is screened through a 30-mesh sieve, which redisperses the pseudo-agglomerates generated during calcination, thus obtaining semiconductor powder materials with better flowability.

[0038] Example 3

[0039] (1) First, zinc telluride (ZnTe) semiconductor material is pulverized to prepare the required particle size (60μm~400μm).

[0040] (2) The pulverized ZnTe semiconductor material powder is loaded into a graphite boat and then into a horizontal calcining furnace.

[0041] (3) Inert gas (N2) is introduced into the horizontal calcining furnace at a flow rate of 10 L / min. After 30 min, the air in the furnace is completely replaced. Then the flow rate is adjusted to 2 L / min and the gas is continuously introduced.

[0042] (4) The horizontal calcining furnace is slowly heated to 900℃ at 5℃ / min, and then held at the temperature for 4 hours for sintering.

[0043] (5) After the heat preservation is completed, the temperature will naturally drop to room temperature, the furnace will be opened, and the material will be discharged.

[0044] (6) The material exiting the furnace is screened through a 30-mesh sieve, which redisperses the pseudo-agglomerates generated during calcination, thus obtaining semiconductor powder materials with better flowability.

[0045] Comparative Example 1

[0046] Compared with Example 1, the temperature of the heat preservation sintering in step (4) of this comparative example is reduced to 700°C, while the rest are the same.

[0047] Comparative Example 2

[0048] Compared with Example 3, the temperature of the heat preservation sintering in step (4) of this comparative example is increased to 1000℃, and the rest are the same.

[0049] The flowability of the semiconductor powder materials obtained in the above examples and comparative examples before calcination in step (1) and after calcination in step (6) (5 samples were tested for each example) was tested using a Hall flow meter. The results are shown in Table 1 below.

[0050] Table 1. Results of flowability tests of ZnTe powder before and after calcination in Examples 1-3

[0051]

[0052] As shown in Table 1, the present invention can significantly improve the flowability of ZnTe semiconductor powder by subjecting it to high-temperature calcination at 800–900℃. Too low a sintering temperature has little effect on improving flowability, while too high a sintering temperature can lead to powder agglomeration.

[0053] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for improving the flowability of a powder of a semiconductor material by high-temperature calcination, characterized by, Includes the following steps: (1) After the semiconductor material zinc telluride is crushed to a particle size of 60μm~400μm, it is loaded into a graphite boat and then into a horizontal calcining furnace; (2) Inert gas is introduced into the horizontal calcining furnace to replace the air, and then inert gas is continuously introduced for protection; (3) Heat the horizontal calcining furnace to 800~900℃ and keep it at that temperature for calcination for 4~8 hours; (4) After the material is heated and calcined in step (3), it is naturally cooled to room temperature, and then screened to redisperse the pseudo-agglomerates generated by calcination, so as to obtain semiconductor powder material with better flowability.

2. The method for improving the flowability of the semiconductor material powder by high-temperature calcination according to claim 1, characterized in that, The introduction of inert gas to replace air in step (2) refers to the introduction of N2 at a flow rate of 10L / min for 30min; the continuous introduction of inert gas for protection refers to the continuous introduction of N2 at a flow rate of 2L / min for protection.

3. The method of claim 1, wherein the high-temperature calcination is performed at a temperature of 800-1,000°C for 1-5 hours. The heating rate in step (3) is 5~10℃ / min.

4. The method of claim 1, wherein the high-temperature calcination is performed at a temperature of 800-1,000°C for 1-5 hours. The sieving mentioned in step (4) refers to sieving using a 30-mesh sieve.

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