阅读说明：本技术 一种用于碱蒸汽腐蚀碳化硅晶片的装置 (Device for etching silicon carbide wafer by alkali vapor ) 是由 李佳君 王蓉 罗昊 朱如忠 皮孝东 杨德仁 于 2021-07-28 设计创作，主要内容包括：本申请公开了一种用于碱蒸汽腐蚀碳化硅晶片的装置,包括：反应部,反应部包括硅晶圆安装部和耐腐蚀腔；加热部,加热部与反应部相连,加热部用于对耐腐蚀腔加热；封堵部,封堵部包括第一管堵和第二管堵；通过设置管堵,实现对反应部的密封,保障腐蚀效果；通过在管堵设置冷凝区和反应区,实现对高温碱性蒸汽的吸收和反应,减少碱性蒸汽散发的空气中对人体健康造成影响。(The application discloses a device for alkali vapor etching silicon carbide wafer, including: the reaction part comprises a silicon wafer mounting part and a corrosion-resistant cavity; the heating part is connected with the reaction part and is used for heating the corrosion-resistant cavity; the plugging part comprises a first pipe plug and a second pipe plug; by arranging the pipe plug, the sealing of the reaction part is realized, and the corrosion effect is guaranteed; the pipe plug is provided with the condensation area and the reaction area, so that the high-temperature alkaline steam is absorbed and reacted, and the influence on the human health caused by the air emitted by the alkaline steam is reduced.)

1. An apparatus for alkali vapor etching a silicon carbide wafer for etching the silicon carbide wafer, comprising:

the reaction part is a tubular container and comprises a steam cavity;

the silicon carbide wafer mounting component is mounted in the steam cavity and used for placing a silicon carbide wafer;

the corrosion-resistant boat is positioned in the steam cavity and is provided with a steam outlet, and the corrosion-resistant boat is used for containing an alkaline corrosive agent;

the heating part is used for heating the corrosion-resistant boat and enabling the alkaline corrosive to generate alkaline steam; and

the pipe plug is used for sealing the reaction part and absorbing the alkaline steam, and the pipe plug is detachably connected to the reaction part;

the pipe plug comprises:

the condensation area is filled with a corrosion-resistant porous heat-insulating material for cooling the alkaline steam;

and the reaction zone is filled with a corrosion-resistant porous material which is easy to react with alkaline gas.

2. The apparatus of claim 1, wherein the reaction part, the silicon carbide wafer mounting part and the corrosion-resistant boat are made of nickel.

3. The apparatus of claim 1, wherein the reaction component is provided with a first mounting portion for mounting the corrosion-resistant boat and a second mounting portion for mounting the silicon carbide wafer mounting component.

4. The apparatus of claim 1, wherein the silicon carbide wafer mounting member is provided with a plurality of slots for mounting the silicon carbide wafer.

5. The apparatus of claim 1 wherein said corrosion resistant boat corresponds to said heating means.

6. The apparatus of claim 1, wherein the corrosion-resistant porous thermal insulation material is zirconia cellucotton and the corrosion-resistant porous material is alumina cellucotton.

7. The device for etching the silicon carbide wafer by the alkali vapor according to claim 1, wherein the pipe plug comprises a mounting frame, a first plugging disc and a second plugging disc connected to the mounting frame, the condensation zone is located between the first plugging disc and the second plugging disc, the reaction zone is located on the side of the second plugging disc away from the first plugging disc, the first plugging disc is provided with a plurality of first through holes, the second plugging disc is provided with a plurality of second through holes, the first through holes facilitate the alkali vapor to enter the condensation zone, the second through holes facilitate the alkali vapor in the condensation zone to enter the reaction zone, and the mounting frame is further provided with a handle which facilitates the disassembly and assembly of the pipe plug.

8. The apparatus of claim 1, wherein the heating component is a tube furnace adapted to the reaction component, the tube furnace encasing the reaction component.

Technical Field

The invention relates to the field of silicon carbide wafer processing, in particular to a device for etching a silicon carbide wafer by using alkali vapor.

Background

The silicon carbide is one of the most widely researched third-generation semiconductor materials at present, has good application prospects in the fields of photovoltaics, new energy automobiles, smart power grids and the like, and has good economic benefits and high application value due to continuous release of related researches and products.

One significant problem that currently limits the use of silicon carbide devices is wafer defects. Through continuous efforts in scientific research and industry, defects such as inclusions, gaps, polytype and the like of high-quality silicon carbide wafers can be completely eliminated, and defects such as micropipes and dislocations become the focus of current attention. Micropipes can cause direct failure of the device, and dislocations such as edge dislocations, screw dislocations, basal plane dislocations, and the like can reduce carrier lifetime and affect device performance. Therefore, locating and analyzing such defects is an important requirement for material preparation and device fabrication.

Corrosion is the primary means of defect characterization of silicon carbide. By controlling the progress of the etching, a rapid differentiation of one or several defects can be achieved. The high-temperature alkali steam has a good distinguishing effect on the silicon carbide corrosion defects. However, no special etching device is available at present for such work due to the high temperature required for etching by alkali vapor and the difficulty of treatment by alkali vapor.

Disclosure of Invention

The invention aims at the problems and provides a device for alkali vapor etching of a silicon carbide wafer.

The technical scheme adopted by the invention is as follows: an apparatus for alkali vapor etching a silicon carbide wafer for etching the silicon carbide wafer, comprising:

the reaction part is a tubular container and comprises a steam cavity;

the silicon carbide wafer mounting component is mounted in the steam cavity and used for placing a silicon carbide wafer;

the corrosion-resistant boat is positioned in the steam cavity and is provided with a steam outlet, and the corrosion-resistant boat is used for containing an alkaline corrosive agent;

the heating part is used for heating the corrosion-resistant boat and enabling the alkaline corrosive to generate alkaline steam;

the pipe plug is used for sealing the reaction part and absorbing the alkaline steam, and the pipe plug is detachably connected to the reaction part;

the pipe plug comprises:

the condensation area is filled with a corrosion-resistant porous heat-insulating material for cooling the alkaline steam;

and the reaction zone is filled with a corrosion-resistant porous material which is easy to react with alkaline gas.

When the device is actually used, a silicon carbide wafer to be processed is placed on a silicon carbide wafer mounting part, the silicon carbide wafer mounting part is placed inside a steam cavity, then an alkaline corrosive agent is injected into the corrosion-resistant boat, a pipe plug is mounted on a reaction part, the reaction part is sealed, finally, a heating part is started, the heating part heats the alkaline corrosive liquid and generates high-temperature alkaline steam, and the alkaline high-temperature steam corrodes the silicon carbide wafer mounted on the silicon carbide wafer mounting part; filling a corrosion-resistant porous heat-insulating material into a condensation area, filling a corrosion-resistant porous material which is easy to react with alkaline gas into a reaction area, firstly, contacting high-temperature alkaline steam generated by heating with the condensation area of the pipe plug, cooling and adsorbing the high-temperature alkaline steam by the corrosion-resistant porous material in the condensation area, contacting the cooled high-temperature alkaline steam with the reaction area, and neutralizing and absorbing the high-temperature alkaline steam in the reaction area; the reaction part is a tubular container, so that the reaction part is convenient to mount and move, and meanwhile, the tubular shape is adopted, the heating area is effectively increased, and the corrosion efficiency of high-temperature alkaline steam on the silicon carbide wafer is improved.

Preferably, the reaction member, the silicon carbide wafer mounting member, and the corrosion-resistant boat are made of nickel.

The reaction part, the silicon carbide wafer mounting part and the corrosion-resistant boat are made of nickel, and the nickel has good corrosion resistance to alkaline gas, so that the service life of the parts is effectively guaranteed.

Preferably, the reaction part is provided with a first mounting part and a second mounting part, the first mounting part is used for mounting the corrosion-resistant boat, and the second mounting part is used for mounting the silicon carbide wafer mounting part.

The corrosion-resistant boat is convenient to mount by arranging the first mounting part; through setting up the second installation department, the installation of the carborundum wafer installing component of realizing being convenient for increases simultaneously corrosion-resistant boat and the stability of carborundum wafer installing component on reaction unit.

Preferably, the silicon carbide wafer mounting member is provided with a plurality of slots for mounting the silicon carbide wafer.

Through setting up a plurality of slots, realize corroding a plurality of carborundum wafers simultaneously, realized improving work efficiency, practiced thrift the purpose of processing cost.

Preferably, the corrosion-resistant boat corresponds to the heating member.

Corresponding with the heater block through setting up corrosion-resistant boat, the heater block is to corrosion-resistant boat heating, makes the quick alkaline steam that generates of alkaline corrosion agent in the corrosion-resistant boat, and the promotion efficiency reduces the heat and runs off, reaches the purpose of energy saving.

Preferably, the porous heat-insulating material is zirconia cellucotton, and the zirconia cellucotton has good high-temperature oxidation resistance, low thermal conductivity, and strong corrosion resistance and adsorption capacity; the corrosion-resistant porous material is alumina cellucotton; the alumina fiber cotton is easy to absorb alkaline gas, and meanwhile, the alumina short fiber has outstanding high-temperature resistance and long service life.

Preferably, the pipe plug comprises an installation frame, a first plugging disc and a second plugging disc, the first plugging disc and the second plugging disc are connected to the installation frame, the condensation area is located between the first plugging disc and the second plugging disc, the reaction area is located on one side, away from the first plugging disc, of the second plugging disc, a plurality of first through holes are formed in the first plugging disc, a plurality of second through holes are formed in the second plugging disc, alkaline steam enters the condensation area through the first through holes, alkaline steam in the condensation area enters the reaction area through the second through holes, a handle is further arranged on the installation frame, and the handle is convenient for dismounting the pipe plug.

The first through hole and the second through hole are formed in the first blocking disc and the second blocking disc, so that the purpose of facilitating high-temperature alkaline steam to enter a condensation area and a reaction area is achieved; the purpose of facilitating the disassembly and assembly of the pipe plug is achieved by arranging the handle on the mounting frame.

Preferably, the heating component is a tube furnace adapted to the reaction component, and the tube furnace surrounds the reaction component.

By adopting the tube furnace, the surrounding heating is realized, the heating efficiency is improved, the heat loss is reduced, and the purposes of quick reaction and energy conservation are achieved.

The invention has the beneficial effects that: the reaction part is a tubular container, so that the reaction part is convenient to mount and move, and meanwhile, the tubular shape is adopted, so that the heating area is effectively increased, and the corrosion efficiency of high-temperature alkaline steam on the silicon carbide wafer is improved; by arranging the pipe plug, the sealing of the reaction part is realized, and the corrosion effect is guaranteed; the pipe plug is provided with the condensation area and the reaction area, so that the absorption and the reaction of high-temperature alkaline steam are realized, and the influence on the human health caused by air emitted by the alkaline steam is effectively reduced; by adopting the tube furnace, the heating efficiency is improved, the heat loss is reduced, and the purposes of quick reaction and energy conservation are achieved.

Description of the drawings:

FIG. 1 is a schematic view of an apparatus for alkali vapor etching a silicon carbide wafer;

FIG. 2 is a cross-sectional view of the reaction parts with the corrosion-resistant boat and the carbonized wafer mounted parts;

FIG. 3 is a schematic view of a reaction part and a corrosion resistant boat;

FIG. 4 is a schematic view of a pipe plug;

FIG. 5 is a schematic view of a corrosion resistant boat;

FIG. 6 is a schematic view of a SiC wafer mounting assembly;

FIG. 7 is a schematic view of a heating unit and a reaction unit.

The figures are numbered:

1. a reaction member; 2. a steam chamber; 3. a corrosion resistant boat; 4. a heating member; 5. pipe blocking; 6. carbonizing the wafer mounting member; 7. a slot; 8. a condensation zone; 9. a reaction zone; 10. a first plugging disc; 11. a second plugging disc; 12. a first through hole; 13. a second through hole; 14. installing a frame; 15. and (4) a handle.

The specific implementation mode is as follows:

the present invention will be described in detail below with reference to the accompanying drawings.

As shown in fig. 1 to 5, an apparatus for alkali vapor etching a silicon carbide wafer for etching the silicon carbide wafer, comprising:

the reaction part 1 is a tubular container, and the reaction part 1 comprises a steam cavity 2;

a silicon carbide wafer mounting part 6 which is mounted in the steam chamber 2 and used for placing a silicon carbide wafer;

the corrosion-resistant boat 3 is positioned in the steam cavity 2 and is provided with a steam outlet, and the corrosion-resistant boat 3 is used for containing an alkaline corrosive agent;

a heating member 4 for heating the corrosion-resistant boat 3 and generating an alkaline vapor from the alkaline etchant;

the pipe plug 5 is used for sealing the reaction part and absorbing alkaline steam, and the pipe plug 5 is detachably connected to the reaction part;

the pipe plug 5 includes:

the condensation area 8 is filled with a corrosion-resistant porous heat-insulating material for cooling the alkaline steam;

the reaction zone 9, the reaction zone 9 is filled with corrosion-resistant porous material which is easy to react with alkaline gas.

During actual use, a silicon carbide wafer to be processed is placed on the silicon carbide wafer mounting part 6, the silicon carbide wafer mounting part is placed inside the steam cavity 2, then an alkaline corrosive agent is injected into the corrosion-resistant boat 3, the pipe plug 5 is mounted on the reaction part 1, the reaction part 1 is sealed, finally the heating part 4 is started, the heating part 4 heats the alkaline corrosive liquid and generates high-temperature alkaline steam, and the alkaline high-temperature steam corrodes the silicon carbide wafer mounted on the silicon carbide wafer mounting part; filling a corrosion-resistant porous heat-insulating material into a condensation area 8, filling a corrosion-resistant porous material which is easy to react with alkaline gas into a reaction area 9, firstly, heating to generate high-temperature alkaline steam to be contacted with the condensation area 8 of the pipe plug 5, cooling and adsorbing the high-temperature alkaline steam by the corrosion-resistant porous material in the condensation area 8, contacting the cooled high-temperature alkaline steam with the reaction area 9, and neutralizing and absorbing the high-temperature alkaline steam in the reaction area 9; reaction unit 1 is the tubular container, and the installation and the removal of reaction unit 1 of being convenient for adopt the tubulose appearance simultaneously, effectively increase the heated area, have promoted the corrosion efficiency of high temperature alkaline steam to carborundum wafer.

The reaction part 1, the silicon carbide wafer mounting part 6, and the corrosion-resistant boat 3 are all made of nickel.

The reaction part 1, the silicon carbide wafer mounting part 6 and the corrosion-resistant boat 3 are made of nickel, and the nickel has good corrosion resistance to alkaline gas, so that the service lives of the parts are effectively guaranteed.

As shown in fig. 2, the reaction member 1 is provided with a first mounting portion for mounting the corrosion-resistant boat 3 and a second mounting portion for mounting the silicon carbide wafer mounting member 6.

The corrosion-resistant boat 3 is convenient to mount by arranging the first mounting part; by providing the second mounting portion, it is achieved that the silicon carbide wafer mounting part 6 can be mounted conveniently, and the stability of the corrosion-resistant boat 3 and the silicon carbide wafer mounting part 6 on the reaction part 1 is increased.

As shown in fig. 6, the sic wafer mounting member 6 is provided with a plurality of slots 7, and the slots 7 are used for mounting sic wafers.

Through setting up a plurality of slots 7, realize corroding a plurality of carborundum wafers simultaneously, realized improving work efficiency, practice thrift the purpose of processing cost.

The corrosion-resistant boat 3 corresponds to the heating member 4.

Corresponding with heating part 4 through setting up corrosion-resistant boat 3, heating part 4 heats to corrosion-resistant boat 3, makes the quick alkaline steam that generates of the alkaline corrosion agent in the corrosion-resistant boat 3, and the raising efficiency reduces the heat and runs off, reaches the purpose of energy saving.

The porous heat-insulating material is zirconia cellucotton, and the zirconia cellucotton has good high-temperature oxidation resistance, low heat conductivity coefficient, and strong corrosion resistance and adsorption capacity; the corrosion-resistant porous material is alumina cellucotton; the alumina fiber cotton is easy to absorb alkaline gas, and meanwhile, the alumina short fiber has outstanding high-temperature resistance and long service life.

As shown in fig. 4, the pipe plug 5 includes a mounting frame 14, a first plugging disc 10 and a second plugging disc 11 connected to the mounting frame 14, the condensation area 8 is located between the first plugging disc 10 and the second plugging disc 11, the reaction area 9 is located on one side of the second plugging disc 11 far away from the first plugging disc 10, a plurality of first through holes 12 are provided on the first plugging disc 10, a plurality of second through holes 13 are provided on the second plugging disc 11, the first through holes 12 facilitate alkaline steam to enter the condensation area 8, the second through holes 13 facilitate alkaline steam of the condensation area 8 to enter the reaction area 9, a handle 15 is further provided on the mounting frame 14, and the handle 15 facilitates dismounting and mounting of the pipe plug 5.

The purpose of facilitating high-temperature alkaline steam to enter the condensation zone 8 and the reaction zone 9 is achieved by arranging the first through hole 12 and the second through hole 13 on the first blocking disc 10 and the second blocking disc 11; the purpose of facilitating the disassembly and assembly of the pipe plug 5 is achieved by arranging the handle 15 on the mounting frame 14.

As shown in fig. 7, the heating member 4 is a tube furnace fitted to the reaction member 1, and the tube furnace surrounds the reaction member 1.

By adopting the tube furnace, the surrounding heating is realized, the heating efficiency is improved, the heat loss is reduced, and the purposes of quick reaction and energy conservation are achieved.

Example 2

This embodiment differs from embodiment 1 in that the reaction member 11 is provided with an opening only at one end, and the opening is sealed with a single pipe plug 5.

The use method of the invention comprises the following steps: firstly, placing a plurality of silicon carbide wafers to be corroded into slots 7 of a silicon carbide wafer mounting part 6, placing the silicon carbide wafer mounting part 6 into a steam cavity 2 of a reaction part 1, injecting an alkaline solution into a corrosion-resistant boat 3 and placing the alkali solution into the steam cavity 2, and respectively filling a condensation zone 8 and a reaction zone 9 of a pipe plug 5 with a corrosion-resistant porous heat-insulating material and a porous heat-insulating material which can easily react with alkaline steam; then the pipe plug 5 is mounted on the reaction part 1, thereby sealing the reaction part 1; and finally, placing the reaction part into a tubular furnace, opening the tubular furnace, heating the alkaline solution in the corrosion-resistant boat 3 by the tubular furnace, generating alkaline gas by the alkaline solution, filling the steam cavity 2 of the reaction part 1 with the alkaline gas, corroding the silicon carbide wafer by the alkaline gas, and simultaneously condensing and reacting the alkaline gas by the condensation area 8 and the reaction area 9 of the pipe plug 5 respectively to ensure that the alkaline gas cannot escape from the reaction part 1.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all equivalent structural changes made by using the contents of the present specification and the drawings, which are directly or indirectly applied to other related technical fields, are included in the scope of the present invention.