Semiconductor phosphide implantation synthesis system and control method

Abstract

The semiconductor phosphide injection synthesis system and control method belong to the technical field of semiconductor phosphide production, and include a furnace body, a shielded storage box installed above the furnace body by a lifting mechanism, a phosphorus source carrier installed in the shielded storage box, an injection tube installed below the phosphorus source carrier, and a crucible installed at the bottom of the furnace body, the phosphorus source carrier includes a phosphorus source carrier body and an upper cover of the phosphorus source carrier, a heating element seat installed at the bottom of the phosphorus source carrier body, and a heating element installed in the heating element seat, the outer wall of the phosphorus source carrier is wrapped in a heat insulating layer, and an induction coil is installed between the heat insulating layer and the inner wall of the shielded storage box. By improving the device and the method themselves, the stability of the system can be improved, quantitative synthesis in the synthesis system is possible, and the risk of phosphorus source carrier explosion is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor phosphide manufacturing, and specifically relates to a semiconductor phosphide implantation synthesis system and a control method.

Background Art

[0002] Semiconductor phosphides mainly include semiconductor materials such as indium phosphide and gallium phosphide. Indium phosphide devices have the characteristics of high frequency, high speed, radiation resistance, and low noise, and the operating frequency has reached 3 THz. When the operating frequency of the device exceeds 100 GHz, indium phosphide shows obvious advantages. InP has already become an important semiconductor material in ultra-high frequency, ultra-high speed devices, and optoelectronic devices. With the future development of terahertz, millimeter wave, optical communication, autonomous driving, Internet of Things, and 5G / 6G technologies, InP will play a greater role and generate more social benefits. Since phosphides have a very high saturated vapor pressure at the melting point, they are difficult to manufacture.

[0003] The synthesis methods of phosphides are mainly horizontal diffusion synthesis and implantation synthesis. Generally, horizontal diffusion synthesis is simpler in technology, but it requires a long time, the purity of the raw materials is low, and it is difficult to obtain high-quality polycrystalline materials. The phosphide implantation synthesis technology is an excellent polycrystalline manufacturing method, characterized by fast synthesis completion and high purity of the raw materials. The drawback is that in order to ensure the utilization rate of phosphorus, it is necessary to suppress the implantation synthesis speed, so the explosion of the phosphorus source carrier is likely to occur. When the synthesis amount is large, the mass of red phosphorus in the phosphorus source carrier increases, and it becomes difficult for red phosphorus to receive heat evenly, the thermal response ability of the system deteriorates, and the temperature control ability of the system decreases, so the risk of phosphorus source carrier explosion increases. Since single crystal materials are manufactured from polycrystalline materials, there is a demand for an implantation synthesis device with high synthesis purity, high synthesis efficiency, and high phosphorus utilization rate. The prior art document information related to the invention of this application is as follows (including documents cited at the international stage after the international filing date and documents cited when entering the national phase in other countries). (Prior art document) (Patent document) (Patent document 1) Specification of Chinese Patent Application Publication No. 112708935 (Patent document 2) Specification of Chinese Patent Application Publication No. 108358180 (Patent document 3) Specification of Chinese Patent Application Publication No. 107747125 (Patent document 4) Specification of US Patent Application Publication No. 2004 / 173140 (Patent document 5) Specification of Chinese Patent Application Publication No. 101660207

Summary of the Invention

Problems to be Solved by the Invention

[0004] The technical problem to be solved by the present invention is to provide a semiconductor phosphide injection synthesis system and a control method. By improving the device and method itself, the stability of the system can be improved, quantitative synthesis in the synthesis system becomes possible, and the risk of phosphorus source carrier explosion is reduced.

Means for Solving the Problems

[0005] The technical solution adopted by the present invention is as follows. A semiconductor phosphide injection synthesis system including a furnace body, a shielding storage box provided above the furnace body by a lifting mechanism, a phosphorus source carrier provided in the shielding storage box, an injection pipe provided below the phosphorus source carrier, and a crucible provided at the bottom inside the furnace body. The phosphorus source carrier includes a main body of the phosphorus source carrier and an upper lid of the phosphorus source carrier, a heating element seat provided at the bottom inside the main body of the phosphorus source carrier, and a heating element provided on the heating element seat. The outer wall of the phosphorus source carrier is wrapped by a heat insulation layer, and an induction coil is provided between the heat insulation layer and the inner wall of the shielding storage box.

[0006] The control method realized by the semiconductor phosphide injection synthesis system includes the following steps. In step 1, red phosphorus and high-purity indium are respectively put into the phosphorus source carrier and the crucible. Next, a boron oxide coating agent is coated on the high-purity indium. After evacuating the furnace body from the ventilation port of the furnace body and then injecting an inert gas, the preparation work is completed. In step 2, the crucible is heated by a main resistance heater to melt the high-purity indium to obtain a melt. In step 3, heat the pressure measurement system with the secondary heater, observe the solid boron oxide column through the observation window a, record the indicated temperature T1 of the thermocouple a after melting and the indication L1 on the scale, calculate the volume V1 of the remaining space in the upper part of the pressure equilibrium tube according to the diameter of the pressure equilibrium tube, and then obtain the value of the gas pressure P1 in the pressure equilibrium tube at this time according to the gas pressure calculation formula. In step 4, then, lower the phosphorus source carrier by the lifting mechanism towards the melt until the injection tube is located near the bottom of the crucible. At this time, the thermocouple b also enters the insertion groove. In step 5, turn on the induction coil, observe the foaming state in the injection tube through the observation window b, record the indicated temperature T2 of the thermocouple a when foaming begins and the indication L2 on the scale, calculate the volume V2 of the remaining space in the upper part of the pressure equilibrium tube according to the diameter of the pressure equilibrium tube, and then obtain the value of the gas pressure P2 in the pressure equilibrium tube at this time according to the formula P1V1 / T1 = P2V2 / T2. In step 6, according to the pressure difference formula ΔP = P2 - P0, keep ΔP between 0.05 and 0.1Pe to control the foaming speed of the injection tube. Here, P0 represents the value of the pressure gauge, and Pe represents the saturated vapor pressure at the melting point. The method for controlling the foaming speed in the injection tube is as follows. Based on the feedback of the indicated temperature of the thermocouple b, adjust the magnitude of the current of the induction coil in real time to adjust the temperature in the phosphorus source carrier, make P2 in the phosphorus source carrier constant, and further realize the constancy of the foaming speed in the injection tube. In step 7, after the synthesis is completed, turn off the induction coil and the secondary heater, reset the phosphorus source carrier, and the injection tube is separated from the boron oxide coating agent.

Advantages of the Invention

[0007] The present invention has the following beneficial effects. The induction coil causes a plurality of heating elements in the phosphorus source carrier to generate heat, heating the red phosphorus, which is thereby uniformly heated, volatilized, and injected into the melt. Further, a pressure and temperature measurement balance system is provided in the phosphorus source carrier. By measuring the internal pressure and temperature of the synthesis system under a corrosive atmosphere and an induction magnetic field in combination with the saturated vapor pressure of phosphorus, the entire synthesis system can be monitored and controlled. The device is particularly suitable for large-scale synthesis, enabling the synthesis system to receive heat more uniformly, improving stability, enabling quantitative synthesis in the synthesis system, and reducing the risk of explosion of the phosphorus source carrier.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0009] As shown in reference to Figures 1 to 3, a semiconductor phosphide injection synthesis system includes a furnace body, a shielding and accommodating box 2 provided above the furnace body by a lifting mechanism 20, a phosphorus source carrier 11 provided in the shielding and accommodating box 2, an injection pipe 6 provided below the phosphorus source carrier 11, and a crucible 13 provided side by side at the bottom inside the furnace body. The phosphorus source carrier 11 includes a main body 11-2 of the phosphorus source carrier, an upper lid 11-1 of the phosphorus source carrier, a heating element seat 4 provided at the bottom inside the main body 11-2 of the phosphorus source carrier, and a heating element 12 provided on the heating element seat 4. The outer wall of the phosphorus source carrier 11 is wrapped by a heat insulation layer 7, and an induction coil 1 is provided between the heat insulation layer 7 and the inner wall of the shielding and accommodating box 2. A pressure gauge 23 is further provided outside the furnace body.

[0010] A pressure measurement system is provided on the upper cover 11-1 of the phosphorus source carrier. The pressure measurement system includes a pressure balance tube 10-2 welded to the upper cover 11-1 of the phosphorus source carrier, a solid boron oxide column 17 provided in the pressure balance tube 10-2, a pressure measurement sealing cap 10-1 equipped with a thermocouple a 8, and a secondary heater 21 provided on the outer wall of the pressure balance tube 10-2. The pressure measurement sealing cap 10-1 is welded to the upper end of the pressure balance tube 10-2. An air supply hole 10-4 communicating with the phosphorus source carrier 11 is provided at the lower end of the pressure balance tube 10-2. An observation scale 10-3 is provided on the pressure balance tube 10-2, and an observation window a 18 is provided on the upper end surface of the furnace body.

[0011] The thermocouple wire of the thermocouple a 8 is connected to a sensor outside the furnace body.

[0012] An insertion groove 11-3 for accommodating a thermocouple b 22 is provided at the bottom of the main body 11-2 of the phosphorus source carrier. The thermocouple b 22 is in the shape of 'J', its upper end is provided in the insertion groove 11-3, and the left side is connected to the furnace body.

[0013] A main resistance heater 15 is provided around the outer wall of the crucible 13, and an observation window b 19 adapted to the crucible 13 is provided in the middle of the furnace body.

[0014] The control method of the semiconductor phosphide injection synthesis system includes the following steps. In step 1, red phosphorus 3 and high-purity indium are respectively placed in the phosphorus source carrier 11 and the crucible 13. Then, a boron oxide coating agent 14 is coated on the high-purity indium. After evacuating the furnace body from the ventilation port of the furnace body, an inert gas is injected to complete the preparation work. In step 2, the crucible 13 is heated by the main resistance heater 15 to melt the high-purity indium to obtain a melt. In Step 3, heat the pressure measurement system 10 with the secondary heater 21, observe the solid boron oxide column 17 through the observation window a 18, record the displayed temperature T1 of the thermocouple a 8 after melting and the indication L1 on the scale 10-3, calculate the volume V1 of the remaining space in the upper part of the pressure equilibrium tube 10-2 based on the diameter of the pressure equilibrium tube 10-2, and then obtain the value of the gas pressure P1 in the pressure equilibrium tube 10-2 at this time according to the gas pressure calculation formula. In Step 4, then, lower the phosphorus source carrier 11 by the lifting mechanism 20 towards the melt until the injection tube 6 is positioned near the bottom of the crucible. At this time, the thermocouple b 22 also enters the insertion groove 11-3. In Step 5, turn on the induction coil 1, observe the foaming state in the injection tube 6 through the observation window b 19, record the displayed temperature T2 of the thermocouple a 8 when foaming starts and the indication L2 on the scale 10-3, calculate the volume V2 of the remaining space in the upper part of the pressure equilibrium tube 10-2 based on the diameter of the pressure equilibrium tube 10-2, and then obtain the value of the gas pressure P2 in the pressure equilibrium tube 10-2 at this time according to the formula P1V1 / T1 = P2V2 / T2. In Step 6, according to the pressure difference formula ΔP = P2 - P0, maintain ΔP between 0.05 and 0.1Pe to control the foaming rate of the injection tube 6. Here, P0 represents the value of the pressure gauge 23, and Pe represents the saturated vapor pressure at the melting point. The method for controlling the foaming rate in the injection tube 6 is as follows. Based on the feedback of the displayed temperature of the thermocouple b 22, adjust the magnitude of the current of the induction coil 1 in real time to adjust the temperature in the phosphorus source carrier 11, make P2 in the phosphorus source carrier 11 constant, and further realize the constancy of the foaming rate in the injection tube 6. In Step 7, after the synthesis is completed, turn off the induction coil 1 and the secondary heater 21, reset the phosphorus source carrier 11, and the injection tube 6 is separated from the boron oxide coating agent 14.

[0015] As a specific embodiment, the thermocouple a 8 is welded to the pressure-measuring and sealing cap 10-1, and the two thermocouple wires are not brought into contact. The pressure balance tube 10-2 is welded to the upper lid 11-1 of the phosphorus source carrier. The solid boron oxide column 17 is placed into the pressure balance tube 10-2. Then, the pressure-measuring and sealing cap 10-1 equipped with the thermocouple a 8 is welded to the pressure balance tube 10-2.

[0016] Then, the heating element 12 is placed into the heating element seat 4 inside the main body 11-2 of the phosphorus source carrier. Then, red phosphorus 3 with a predetermined synthetic mass fraction is placed inside the main body 11-2 of the phosphorus source carrier, and the upper lid 11-1 of the phosphorus source carrier is welded to the main body 11-2 of the phosphorus source carrier.

[0017] Then, the induction coil 1 is placed into the shielding and accommodating box 2. Also, the outer wall of the phosphorus source carrier 11 is wrapped with the heat-insulating layer 7, and then the phosphorus source carrier 11 wrapped by the heat-insulating layer 7 is placed into the induction coil 1.

[0018] Connect the thermocouple wires of the thermocouple a 8 to the sensor outside the furnace body. Attach the observation window a 18 and the observation window b 19 to the furnace body.

[0019] Put high-purity indium and the boron oxide coating agent 14 into the crucible 13, evacuate the system to 10 -5 Pa, and inject an inert gas. Heat the crucible 13 with the main resistance heater 15 to melt the high-purity indium and the boron oxide coating agent 14 to obtain a melt 16 of high-purity indium.

[0020] Heat the pressure-measuring system with the secondary heater 21, observe from the observation window a 18 until the solid boron oxide column 17 melts, and when the thermocouple a 8 stabilizes, record the temperature T1 at this time and the indication L1 on the scale 10-3. Calculate the volume V1 at this time according to the diameter of the pressure balance tube 10-2. The internal pressure and the external pressure are balanced at this time, and the system pressure is P1.

[0021] Thereafter, the elevator mechanism 20 lowers the phosphorus source carrier 11 toward the melt 16, and the thermocouple b 23 is inserted into the insertion groove 11-3 such that the injection tube 6 is positioned 3 to 5 mm above the bottom of the crucible.

[0022] An alternating current is applied to the induction coil 1, and the foaming state in the injection tube 6 is observed through the observation window b 19. At the same time, the indication L2 on the scale 10-3 is observed, the temperature T2 at this time is recorded, and the volume V2 at this time is obtained. The pressure P2 inside the phosphorus source carrier at this time is obtained. The value of P2 is obtained according to the Clapeyron equation P1V1 / T1 = P2V2 / T2. The foaming rate is adjusted according to the pressure difference ΔP = P2 - P0, where P0 is the value of the pressure gauge 23.

[0023] The temperature of the phosphorus source carrier 11 is adjusted by the thermocouple b 22 to obtain a desired foaming rate, and the value of the pressure difference ΔP at this time is obtained. The pressure inside the phosphorus source carrier 11 is measured by the pressure measurement system 10. Since the heat conductivity of the liquid boron oxide column 9 is poor, the temperature feedback is slow. The temperature control system cannot perform feedback control on the power of the induction coil 1 by the thermocouple a 8. By feeding back the power of the induction coil 1 by the thermocouple b 22 and adjusting the temperature inside the phosphorus source carrier 11, the numerical adjustment of the pressure P2 is realized, and a desired foaming rate is obtained, and the value of the optimal pressure difference ΔP at this time is obtained. As the phosphorus element inside the phosphorus source carrier 11 decreases, the pressure inside the phosphorus source carrier 11 decreases. The temperature control system and the thermocouple b 22 maintain the constancy of the pressure P2 inside the phosphorus source carrier 11 by performing feedback control on the power of the induction coil 1.

[0024] After the synthesis is completed, the currents of the induction coil 1 and the secondary heater 21 are reduced to 0 A. The elevator mechanism 20 lifts the phosphorus source carrier 11, and the injection tube 6 is separated from the boron oxide coating agent 14.

[0025] After the furnace is removed, the system is evacuated to 1 atm, the upper lid 11-1 of the phosphorus source carrier is cut off, and the main body 11-2 of the phosphorus source carrier is cleaned in preparation for the next use. At the same time, the pressure measurement sealing cap 10-1 is cut off in preparation for the next use, and the thermocouple a 8 is left.

Claims

1. A semiconductor phosphide injection synthesis system comprising a furnace body, a shielding and accommodating box (2) provided above the furnace body by a lifting mechanism (20), a phosphorus source carrier (11) provided in the shielding and accommodating box (2), an injection pipe (6) provided below the phosphorus source carrier (11), and a crucible (13) provided side by side at the bottom inside the furnace body, wherein the phosphorus source carrier (11) includes a main body (11-2) of the phosphorus source carrier, an upper lid (11-1) of the phosphorus source carrier, a heating element seat (4) provided at the bottom inside the main body (11-2) of the phosphorus source carrier, and a heating element (12) provided on the heating element seat (4), the outer wall of the phosphorus source carrier (11) is wrapped by a heat insulation layer (7), and an induction coil (1) is provided between the heat insulation layer (7) and the inner wall of the shielding and accommodating box (2). A semiconductor phosphide injection synthesis system characterized by the above.

2. A pressure measurement system is provided on the upper lid (11-1) of the phosphorus source carrier. The pressure measurement system includes a pressure balance pipe (10-2) welded to the upper lid (11-1) of the phosphorus source carrier, a solid boron oxide column (17) provided in the pressure balance pipe (10-2), a pressure measurement sealing cap (10-1) provided with a thermocouple a (8), and a secondary heater (21) provided on the outer wall of the pressure balance pipe (10-2). The pressure measurement sealing cap (10-1) is welded to the upper end of the pressure balance pipe (10-2). An air supply hole (10-4) communicating with the phosphorus source carrier (11) is provided at the lower end of the pressure balance pipe (10-2). An observation scale (10-3) is provided on the pressure balance pipe (10-2), and an observation window a (18) is provided on the upper end surface of the furnace body. The semiconductor phosphide injection synthesis system according to Claim 1, characterized by the above.

3. The semiconductor phosphide injection synthesis system according to Claim 2, characterized in that the thermocouple wire of the thermocouple a (8) is connected to a sensor outside the furnace body.

4. An insertion groove (11-3) for accommodating a thermocouple b (22) is provided at the bottom of the main body (11-2) of the phosphorus source carrier. The thermocouple b (22) forms an inverted L shape, the upper end thereof is provided in the insertion groove (11-3), and the left side is connected to the furnace body. The semiconductor phosphide injection synthesis system according to Claim 1, characterized by the above.

5. The semiconductor phosphide injection synthesis system according to Claim 1, characterized in that a main resistance heater (15) is provided around the outer wall of the crucible (13), and an observation window b (19) adapted to the crucible (13) is provided in the middle of the furnace body.

6. A control method for a semiconductor phosphide injection synthesis system realized by a semiconductor phosphide injection synthesis system, comprising: Step 1: putting red phosphorus (3) and high-purity indium into a phosphorus source carrier (11) and a crucible (13) respectively, then coating a boron oxide coating agent (14) on the high-purity indium, evacuating the furnace body from the vent of the furnace body, and then injecting an inert gas to complete the preparation work; Step 2: heating the crucible (13) with a main resistance heater (15) to melt the high-purity indium to obtain a melt; Step 3: heating the pressure measurement system (10) with a secondary heater (21), observing the solid boron oxide column (17) from the observation window a (18), recording the displayed temperature T1 of the thermocouple a (8) after melting and the indication L1 on the scale (10-3), calculating the volume V1 of the remaining space in the upper part of the pressure balance tube (10-2) according to the diameter of the pressure balance tube (10-2), and then obtaining the value of the gas pressure P1 in the pressure balance tube (10-2) at this time by the gas pressure calculation formula; Step 4: then lowering the phosphorus source carrier (11) by a lifting mechanism (20) towards the melt until the injection tube (6) is positioned near the bottom of the crucible. At this time, the thermocouple b (22) also enters the insertion groove (11-3); Step 5: turning on the induction coil (1), observing the foaming state in the injection tube (6) from the observation window b (19), recording the displayed temperature T2 of the thermocouple a (8) when foaming starts and the indication L2 on the scale (10-3), calculating the volume V2 of the remaining space in the upper part of the pressure balance tube (10-2) according to the diameter of the pressure balance tube (10-2), and then obtaining the value of the gas pressure P2 in the pressure balance tube (10-2) at this time by the formula P1V1 / T1 = P2V2 / T2; Step 6: controlling the foaming rate of the injection tube (6) by maintaining ΔP between 0.05 and 0.1 Pe according to the pressure difference formula ΔP = P2 - P0, where P0 represents the value of the pressure gauge (23), and Pe represents the saturated vapor pressure of red phosphorus at the melting point temperature of indium; The method for controlling the foaming rate in the injection tube (6) is: Step 6: adjusting the temperature in the phosphorus source carrier (11) by adjusting the magnitude of the current of the induction coil (1) in real time based on the feedback of the displayed temperature of the thermocouple b (22), keeping P2 in the phosphorus source carrier (11) constant, and further realizing the constancy of the foaming rate in the injection tube (6). The control method is characterized in that after the synthesis is completed, the induction coil (1) and the secondary heater (21) are turned off, the phosphorus source carrier (11) is reset, and step 7 is included in which the injection tube (6) is separated from the boron oxide coating agent (14).

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