阅读说明：本技术 一种磷化铟尾料制备磷化铟多晶的方法 (Method for preparing indium phosphide polycrystal from indium phosphide tailings ) 是由 陈伟杰 白平平 周铁军 危严 林嘉威 齐正阳 于 2021-09-07 设计创作，主要内容包括：本发明公开了一种磷化铟尾料制备磷化铟多晶的方法,包括：将磷化铟尾料和过量红磷分别置于真空密封石英管的两端,再置于加热器中,将加热器置于压力容器内,在后续的加热过程中磷化铟尾料区域的温度高于红磷区域；加热升温确保在磷化铟尾料区域温度达到磷化铟的熔点前使石英管内压力达到磷化铟的离解压；待石英管内压力到达磷化铟离解压后,将磷化铟区域的温度升至1100～1300℃进行保温；然后对磷化铟区域进行分区域降温以使磷化铟进行定向凝固,得到磷化铟多晶料。本方法不仅能获得良率高的磷化铟多晶,而且可以提高磷化铟废料的利用率,简化工艺,降低生产成本,避免回收铟和磷过程中造成的资源浪费,减少废水废渣的产生,保护环境。(The invention discloses a method for preparing indium phosphide polycrystal by indium phosphide tailings, which comprises the following steps: respectively placing the indium phosphide tailing material and excessive red phosphorus at two ends of a vacuum sealed quartz tube, then placing the quartz tube in a heater, placing the heater in a pressure container, and enabling the temperature of an indium phosphide tailing material area to be higher than that of a red phosphorus area in the subsequent heating process; heating to ensure that the pressure in the quartz tube reaches the decompression release pressure of the indium phosphide before the temperature of the indium phosphide tailing area reaches the melting point of the indium phosphide; after the pressure in the quartz tube reaches indium phosphide decompression pressure, raising the temperature of an indium phosphide area to 1100-1300 ℃ for heat preservation; and then cooling the indium phosphide region in different regions to directionally solidify the indium phosphide to obtain the indium phosphide polycrystal material. The method can obtain the indium phosphide polycrystal with high yield, improve the utilization rate of the indium phosphide waste material, simplify the process, reduce the production cost, avoid resource waste caused in the process of recovering indium and phosphorus, reduce the generation of waste water and waste residue and protect the environment.)

1. A method for preparing indium phosphide polycrystal by using indium phosphide tailings is characterized by comprising the following steps:

(1) crushing the indium phosphide tailing, respectively placing the crushed indium phosphide tailing and excessive red phosphorus at two ends of a quartz tube, vacuumizing the quartz tube and sealing the quartz tube;

(2) pushing the quartz tube into a heater, placing the heater into a pressure container, wherein red phosphorus is positioned in a first area, indium phosphide tailings are positioned in a second area, and the temperature of the second area is higher than that of the first area in the subsequent heating process;

(3) heating to raise the temperature, and ensuring that the pressure in the quartz tube reaches the decompression of the indium phosphide before the temperature of the indium phosphide tailing area reaches the melting point of the indium phosphide;

(4) filling inert gas into the pressure container to ensure that the external pressure of the quartz tube is greater than the internal pressure, and raising the temperature of the second area to 1100-1300 ℃ for heat preservation after the pressure in the quartz tube reaches indium phosphide decompression pressure;

(5) after the heat preservation is finished, the second area is cooled in different areas so as to enable the indium phosphide to be directionally solidified, and then the qualified indium phosphide polycrystal material is obtained.

2. The method for preparing an indium phosphide polycrystal from an indium phosphide tailing as described in claim 1, wherein in the step (3), the temperature in the first zone is raised to 550 to 700 ℃ before the temperature in the second zone reaches the melting point of indium phosphide, so that the pressure in the quartz tube reaches the decompression pressure of indium phosphide.

3. The method for preparing the indium phosphide polycrystal from the indium phosphide tailings as claimed in claim 1, wherein in the step (5), when the temperature is reduced in the sub-areas, a temperature gradient is established along a fixed direction, so that the temperature difference between the lowest temperature area and other areas of the product is ensured to be 50-120 ℃; the directional solidification speed is 5-10 mm/h.

4. The method for preparing the indium phosphide polycrystal from the indium phosphide tailing as described in claim 1, wherein in the step (1), the addition amount of red phosphorus is 99 to 101% of the sum of the theoretical consumption amount X and the amount required for maintaining the decompression, Y, calculated by PV = nRT, P is the decompression, V is the volume in the quartz tube, n is the molar amount of red phosphorus, and T is the actually measured temperature of the first zone.

5. The method for preparing the indium phosphide polycrystal with the indium phosphide tail material as described in claim 1, wherein the pressure of the inert gas in the pressure vessel is from P +1 to P +1.2 atm; where lgP = A-B (T + C), P is the vapor pressure of red phosphorus, T is the actual measured temperature of the first zone, and A, B and C are constants.

6. The method for preparing the indium phosphide polycrystal with the indium phosphide tailing as described in any one of claims 1 to 5, wherein in the step (4), the heat preservation time is 6 to 12 hours.

7. The method for preparing the indium phosphide polycrystal with the indium phosphide tailings as set forth in any one of claims 1 to 5, wherein in the step (4), the temperature of the first zone is 550 to 700 ℃ when the second zone is kept warm.

8. The method for preparing the indium phosphide polycrystal from the indium phosphide tailings as set forth in any one of claims 1 to 5, wherein in the step (1), the indium phosphide tailings are crushed into particles of 5 to 20 mm; the indium phosphide tailing is indium-rich tailing.

9. The method for preparing the indium phosphide polycrystal from the indium phosphide tailings as claimed in any one of claims 1 to 5, characterized by further comprising the step of carrying out pretreatment impurity removal on the indium phosphide tailings before the step (1); the pretreatment comprises the following steps: classifying the indium phosphide tailings according to different doping types, wherein the tailings of different types cannot be mixed together and returned to the furnace, polishing the indium phosphide tailings, cleaning with a cleaning agent, and then washing and drying the cleaning agent for later use.

10. The method for preparing the indium phosphide polycrystal from the indium phosphide tailings as claimed in any one of claims 1 to 5, wherein in the step (5), the inert gas in the pressure vessel is discharged in the process of cooling down in different areas so as to reduce the pressure outside the quartz tube.

Technical Field

The invention belongs to the field of compound semiconductor materials, and particularly relates to a method for preparing indium phosphide polycrystal by using indium phosphide tailings.

Background

Indium phosphide (InP) is an important semiconductor material, has higher electro-optic conversion efficiency, electron mobility, working temperature and strong radiation resistance compared with silicon and gallium arsenide materials, has high development value, and is widely applied to the civil and military fields at present. Indium phosphide (InP) is mainly applied in fields such as terahertz, laser instrument, solar cell, photoelectric detector and optical fiber network system, along with 5G network commercialization, will drive InP substrate material market demand to increase fast. The main demand market of indium phosphide comes from the optical communication market, which accounts for about 82% of the total demand of the market, and the market proportion of indium phosphide in the optical communication field is continuously expanded due to the development of the global optical communication industry.

The dissociation pressure of the indium phosphide crystal at the melting point of the indium phosphide crystal is as high as 27.8bar, high dissociation pressure release determines that the synthesis is very difficult, more indium-rich unqualified products are produced, in addition, the stacking fault of the indium phosphide is low, the ionic property of chemical bonds is strong, the possibility of the occurrence of defects such as twin crystal, dendrite and the like is greatly increased, the processing loss of each procedure of crystal and wafer processing is low, the yield of the indium phosphide is low due to the above points, and more indium phosphide tailings are produced. The indium phosphide tailings are effectively utilized, and the method has important significance for reducing the cost of indium phosphide and improving the market competitiveness.

At present, the method for utilizing indium phosphide tailings is to recover indium and phosphorus from the indium phosphide tailings, and the main processes comprise wet acid leaching and vacuum high-pressure decomposition. The treatment methods have low recovery rate, cause waste of resources and increase the cost for treating waste water and waste residues. The invention provides a method for directly converting indium phosphide tailings into indium phosphide polycrystal by returning, which avoids resource waste generated during recovery, reduces the generation of waste water and waste residues, protects the environment and saves the cost.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides the method for preparing the indium phosphide polycrystal by the indium phosphide tailings, which not only can obtain the indium phosphide polycrystal with high yield, but also can improve the utilization rate of indium phosphide waste materials, simplify the process, reduce the production cost, avoid the resource waste caused in the process of recovering indium and phosphorus, reduce the generation of waste water and waste residues and protect the environment.

In order to achieve the purpose, the invention adopts the following technical scheme:

a method for preparing indium phosphide polycrystal by using indium phosphide tailings comprises the following steps:

(1) crushing the indium phosphide tailing, respectively placing the crushed indium phosphide tailing and excessive red phosphorus at two ends of a quartz tube, vacuumizing the quartz tube and sealing the quartz tube;

(2) pushing the quartz tube into a heater, then placing the heater into a pressure container, wherein red phosphorus is positioned in a first area (a low-temperature area), and indium phosphide tailings are positioned in a second area (a high-temperature area);

(3) before the melting point of indium phosphide is reached, the temperature of a red phosphorus area (low-temperature area) is increased to 550-700 ℃, so that the pressure in the quartz tube reaches the decompression pressure of the indium phosphide, the raw material indium phosphide tailing material in the growth process is ensured not to be decomposed, and the produced crystal bar is prevented from carrying a large amount of indium;

(4) after the pressure of the quartz tube reaches indium phosphide decompression, adjusting the temperature of a heater at one end (high-temperature region) of the quartz boat filled with the indium phosphide tailing material to 1100-1300 ℃, so that the indium phosphide tailing material is thoroughly melted, and preserving heat to ensure that indium in the indium phosphide tailing material is fully contacted and reacted with red phosphorus;

(5) and after the reaction is finished, cooling to obtain the qualified indium phosphide polycrystal material.

Preferably, in the step (3), the temperature of the red phosphorus region (low temperature region) is increased to 550-700 ℃ before the melting point of the indium phosphide is reached, so that the pressure in the quartz tube reaches the decompression pressure of the indium phosphide, because the pressure in the quartz tube does not reach the decompression pressure after the indium phosphide reaches the melting point, the indium phosphide is easily decomposed into phosphorus and indium, a longer time is needed for synthesizing the indium phosphide polycrystal material again, and a large amount of decomposed indium is carried in the indium phosphide polycrystal material synthesized again, so that the yield is greatly reduced, and the purpose of preparing the polycrystal material by using the tailings cannot be achieved.

Preferably, in the step (1), analyzing the components of the indium phosphide tailings, and calculating the input amount of red phosphorus according to the components, the volume of a quartz tube and the like; the method comprises the steps of charging excessive red phosphorus Zg, sampling and analyzing components of indium phosphide tailings, calculating to obtain the amount Xg of red phosphorus required by a synthesis reaction according to the components of indium and phosphorus and the weight of the loaded indium phosphide tailings, calculating to obtain the amount Yg of red phosphorus required by the pressure maintenance according to the volume of a quartz tube and the pressure required in the reaction process by using a Keraberon equation, wherein the amount Y of red phosphorus required by the pressure maintenance is 99-101% of the total amount of X + Y in the actual production process, the amount Y of red phosphorus required by the pressure maintenance is calculated by adopting PV = nRT, P is the pressure maintenance, V is the volume in the quartz tube, n is the molar quantity of red phosphorus, T is the actual measurement temperature of a red phosphorus region, and Y can be calculated according to n.

Preferably, in the step (1), the indium phosphide tailing is crushed into particles of 5-20 mm, and the particles are conveniently placed in a quartz boat, so that the raw materials are fully contacted, and the synthesis reaction is more fully performed.

And placing the quartz boat at one end of the quartz tube, placing the weighed red phosphorus at the other end of the quartz tube, and performing vacuumizing and tube sealing operation. And slowly pushing the sealed quartz tube into a horizontal heater, and then integrally placing the heater and the sealed quartz tube into a stainless steel pressure container.

The indium phosphide polycrystal material is prepared by adopting a horizontal Bridgman method. Preferably, in the reaction process, the pressure in the quartz tube is continuously increased, so that in order to avoid explosion of the quartz tube caused by overhigh pressure in the quartz tube, inert gas needs to be filled into the pressure container to balance the pressure difference between the inside and the outside of the quartz tube; in order to prevent the quartz tube from bursting due to overhigh pressure in the quartz tube, the pressure P at the corresponding temperature T is calculated according to the relationship between the temperature and the pressure in the Antoine equation lgP = A-B (T + C) of red phosphorus. Then, inert gas with the pressure of P + 1-P +1.2atm is filled into the pressure container outside the quartz tube through the gas inlet hole, so that the pressure outside the quartz tube is ensured to be higher than the internal pressure. The temperature T at which the pressure is calculated should be selected based on the actual measured temperature of the red phosphorus region.

Preferably, in the step (4), the heat preservation time is 6 to 12 hours.

Preferably, in the step (4), the temperature of the red phosphorus region is 550 to 700 ℃ during the heat preservation. The temperature of the red phosphorus region is further optimized, so that the requirement on the pressure container is reduced, and the phenomena of explosion, cracking and the like of the quartz tube are avoided.

Preferably, in the step (5), the temperature is reduced in different areas according to the directional solidification principle to perform directional solidification, the temperature of the first cooling area of the product is reduced by 50-120 ℃ compared with the temperature of other areas, and the directional solidification speed is 5-10 mm/h.

Preferably, in the step (5), the inert gas in the pressure vessel needs to be continuously exhausted through the exhaust hole in the whole temperature reduction process so as to reduce the pressure outside the quartz tube. The real-time pressure outside the quartz tube is still calculated by the Antoine equation.

Preferably, in the step (1), before crushing the indium phosphide tailings, the method further comprises a step of performing impurity removal pretreatment on the indium phosphide; the pretreatment comprises the following steps: classifying the indium phosphide tailings according to different doping types, wherein the tailings of different types cannot be mixed together and returned to the furnace, polishing the indium phosphide tailings, cleaning with a cleaning agent, and then washing and drying the cleaning agent for later use.

The specific operation of the pretreatment preferably includes: the method is characterized in that indium phosphide tailings are used as raw materials, doping types are firstly classified, the indium phosphide tailings are divided into non-indium phosphide-doped tailings, sulfur-doped indium phosphide tailings, iron-doped indium phosphide tailings, zinc-doped indium phosphide tailings and the like, and the tailings of different types cannot be mixed together and recycled, so that partial impurity elements of the produced product are prevented from exceeding the standard. After classification, the indium phosphide tailings are polished by 400-sand 800-mesh sand paper, then soaked and cleaned by a mixed solution (volume ratio is 1:1: 9) of nitric acid, hydrofluoric acid and deionized water, then subjected to ultrasonic treatment, washed by deionized water, and then dehydrated and dried for later use; more specifically, the method comprises the following steps: polishing with 400-mesh sand paper of 800 meshes, and soaking the tailings in a solution using a mixed solution of nitric acid, hydrofluoric acid and deionized water (volume ratio is 1:1: 9) as a cleaning agent for 4-6 hours, wherein the mass fraction of the nitric acid is 40-60%, the mass fraction of the hydrofluoric acid is 4-10%, and soaking and washing are required to ensure that the indium phosphide tailings are completely submerged in the solution. And after soaking and washing, carrying out ultrasonic treatment on the indium phosphide tailings for 30-60 minutes, then washing with deionized water for 10-30 minutes, carrying out analytical pure ethanol dehydration, and drying for later use, wherein the drying time is 2-4 hours, and the drying temperature is 60-80 ℃. The above operation can effectively remove the impurity elements on the surface of the indium phosphide tailing.

Compared with the prior art, the invention has the following advantages:

1. the invention utilizes the indium phosphide tailing as the raw material to synthesize the indium phosphide polycrystal material again, and the decomposition of the indium phosphide is inhibited before the pressure is adjusted to the decompression pressure before the melting point of the indium phosphide is reached, thereby reducing the generation of indium-rich, improving the utilization rate of the raw material and effectively reducing the production cost; the method can avoid unnecessary waste of resources, the yield of finished products is up to more than 90%, the recycling process is greatly simplified, the production cost of the indium phosphide polycrystal material is effectively reduced, the market competitiveness of enterprises is improved, and the method meets the long-term development requirements of the enterprises.

2. The traditional treatment method for recovering indium and red phosphorus has low recovery rate, is easy to generate a large amount of waste residues and waste water, and increases the cost for treating the waste residues and the waste water. The method not only recycles all indium phosphide tailings, but also does not produce waste residue and water, does not affect the environment, and is safe and environment-friendly.

Drawings

FIG. 1 is a schematic view of the structure of an apparatus for producing an indium phosphide polycrystal according to the present invention.

Reference numerals:

1. a quartz boat; 2. a quartz tube; 3. a heater; 4. a pressure vessel.

Detailed Description

The invention is further described below with reference to the drawings and specific preferred embodiments of the description, without thereby limiting the scope of protection of the invention.

Example 1:

a method for preparing indium phosphide polycrystal by using indium phosphide tailings, the structure schematic diagram of a preparation device of which is shown in figure 1, specifically comprises the following steps:

selecting a batch of non-indium phosphide-doped tailings, polishing the tailings by using 400-mesh sand paper, soaking the tailings in a mixed solution (volume ratio is 1:1: 9) of nitric acid, hydrofluoric acid and deionized water for 4 hours, putting the mixture into ultrasonic equipment for ultrasonic treatment for 30 minutes, washing the mixture for 20 minutes by using the deionized water, dehydrating the mixture by using analytically pure ethanol, putting the mixture into an oven, and drying the mixture for 3 hours at 70 ℃ for later use. Samples were taken and the contents of components and impurity elements were measured, and the analysis results are shown in Table 1.

4000g of indium phosphide non-doped tailing materials which are cleaned and dried for later use are weighed, crushed into particles of 5-20 mm by a zirconium hammer, and placed in a clean quartz boat for later use.

According to the component results and the volume of the quartz tube, 200g of red phosphorus is weighed and slowly filled into one end of the quartz tube, then the quartz boat filled with the indium phosphide tailing is pushed into the other end of the quartz tube, and the tube is sealed by vacuumizing.

Slowly pushing the quartz tube into a horizontal heater, positioning red phosphorus in a low-temperature region, positioning indium phosphide tailings in a high-temperature region, fixing thermocouples at two ends of the quartz tube, closing a pressure container, introducing cooling water, and starting to heat.

In the temperature rise process, red phosphorus slowly changes into a gas state, fills the whole quartz tube, the pressure in the quartz tube gradually increases, the pressure P at the corresponding temperature T is calculated according to the corresponding relation of the Antoine equation lgP = A-B (T + C), the phosphorus vapor pressure P and the temperature T, and then inert gas with the pressure of P +1 atm is filled into the pressure container outside the quartz tube through the gas inlet hole to ensure that the pressure outside the quartz tube is larger than the internal pressure. The temperature of the low-temperature area is adjusted to 650 ℃, after the pressure of the quartz tube reaches 27.8bar, the temperature of the high-temperature area is adjusted to 1200 ℃ at the heating rate of 3 ℃/h, the temperature is kept for 8 hours, and the temperature of the low-temperature area is kept to 650 ℃ in the period.

After heat preservation is finished, cooling in different areas along the direction from the head to the tail to carry out directional solidification, wherein the temperature difference between the lowest area temperature of the head and the highest area temperature of the tail is 100 ℃, and the directional solidification speed is 8 mm/h.

And when the pressure is reduced to 1bar, opening the pressure container, taking out the quartz tube, cutting the quartz tube cap by using a quartz cutting machine, taking out the quartz boat, and demolding to obtain the qualified indium phosphide polycrystal material 3620g, wherein the yield reaches 90.50%.

The sample was taken to examine GDMS as shown in Table 1.

Example 2:

a method for preparing indium phosphide polycrystal by using indium phosphide tailings, the structure schematic diagram of a preparation device of which is shown in figure 1, specifically comprises the following steps:

selecting a batch of iron-doped indium phosphide tailings, polishing the iron-doped indium phosphide tailings by 600-mesh abrasive paper, soaking the iron-doped indium phosphide tailings in a mixed solution (volume ratio is 1:1: 9) of nitric acid, hydrofluoric acid and deionized water for 6 hours, putting the iron-doped indium phosphide tailings into ultrasonic equipment for ultrasonic treatment for 40 minutes, washing the iron-doped indium phosphide tailings with the deionized water for 20 minutes, dehydrating the iron-doped indium phosphide tailings with analytically pure ethanol, putting the iron-doped indium phosphide tailings into an oven, and drying the iron-doped indium phosphide tailings for 4 hours at 80 ℃ for later use. Samples were taken and the contents of components and impurity elements were measured, and the analysis results are shown in Table 1.

4500g of iron-doped indium phosphide tailing which is washed and dried for later use is weighed, crushed into particles of 5-20 mm by a zirconium hammer, and placed in a clean quartz boat for later use.

According to the component results and the volume of the quartz tube, 230g of red phosphorus is weighed and slowly filled into one end of the quartz tube, then the quartz boat filled with the indium phosphide tailing is pushed into the other end of the quartz tube, and the tube is sealed by vacuumizing.

Slowly pushing a quartz tube into a horizontal heater, wherein red phosphorus is positioned in a low-temperature region, indium phosphide tailings are positioned in a high-temperature region, thermocouples at two ends of the quartz tube are fixed, closing a pressure container, introducing cooling water, and starting heating;

in the temperature rise process, red phosphorus slowly changes into a gas state, fills the whole quartz tube, the pressure in the quartz tube gradually increases, the pressure P at the corresponding temperature T is calculated according to the corresponding relation of the Antoine equation lgP = A-B (T + C), the phosphorus vapor pressure P and the temperature T, and then inert gas with the pressure of P +1 atm is filled into the pressure container outside the quartz tube through the gas inlet hole to ensure that the pressure outside the quartz tube is larger than the internal pressure. The temperature of the low-temperature area is adjusted to 630 ℃ so that the pressure of the quartz tube reaches 27.8bar, then the temperature of the high-temperature area is adjusted to 1250 ℃ at the heating rate of 4 ℃/h, the temperature is preserved for 10 hours, and the temperature of the low-temperature area is kept to 630 ℃ in the period.

After heat preservation is finished, the product is cooled in different areas along the direction from the head to the tail to carry out directional solidification, the temperature difference between the lowest temperature area of the head and the highest temperature area of the tail is 120 ℃, and the directional solidification speed is 8 mm/h.

And when the pressure is reduced to 1bar, opening the pressure container, taking out the quartz tube, cutting the quartz tube cap by using a quartz cutting machine, taking out the quartz boat, and demolding to obtain 4130g of qualified indium phosphide polycrystal material, wherein the yield reaches 91.78%.

The sample was taken to examine GDMS as shown in Table 1.

The foregoing is merely a preferred embodiment of the invention and is not intended to limit the invention in any manner. Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make many possible variations and modifications to the disclosed embodiments, or equivalent modifications, without departing from the spirit and scope of the invention, using the methods and techniques disclosed above. Therefore, any simple modification, equivalent replacement, equivalent change and modification made to the above embodiments according to the technical essence of the present invention are still within the scope of the protection of the technical solution of the present invention.