Semiconductor process cavity structure with cavity self-cleaning function and self-cleaning method thereof

Abstract

The invention discloses a semiconductor process cavity structure with cavity self-cleaning function and a self-cleaning method thereof, belonging to the field of semiconductor technology. The semiconductor process cavity structure adds a CO2 cleaning module on the basis of the original cavity structure of the reaction cavity; the CO2 cleaning module comprises: a liquid CO2 source, a gas source, a mixing container and a nozzle; the liquid CO2 source is used to provide liquid CO2; the gas source is used to provide compressed air or inert gas; the liquid CO2 source and the gas source are respectively connected to the mixing container through a passage A; the liquid CO2 and the compressed air or the inert gas are mixed in the mixing container to form a mixed gas mixed with snowflake-shaped dry ice particles, and the mixed gas is respectively connected to a plurality of nozzles installed in a cavity shell and a pipeline through a passage B; the mixed gas is respectively sprayed into the cavity shell and the pipeline through a plurality of nozzles; the invention can solve the problems that the treatment of the accumulated dirt after a long period of running in the reaction cavity is time-consuming and labor-intensive, and the manual cleaning is easy to be not cleaned up, thereby improving the efficiency of the machine.

Description

Technical Field

[0001] The present invention belongs to the field of semiconductor technology, and in particular relates to a semiconductor process cavity structure with cavity self-cleaning function and a self-cleaning method thereof. Background Art

[0002] Existing semiconductor plasma degumming equipment, plasma etching equipment, plasma thin film deposition equipment, semiconductor cleaning equipment, furnace tube equipment, glue coating equipment and other equipment (hereinafter referred to as machines) are prone to dirt accumulation on the walls of the reaction chambers, the internal parts of the chambers, the corners of the pipes, and the valves such as butterfly valves after a long period of use. When these dirt accumulates to a certain extent, it will affect the use of the machine, causing downtime, and will also affect the process in the chamber and pollute the wafer. Usually, after a certain period of accumulation, the replaced contaminated parts can only be sent out for cleaning by replacing the parts. The parts of the chamber wall that cannot be removed can only be cleaned manually, which is time-consuming, labor-intensive, and easy to be uncleaned, affecting the efficiency of the machine. Summary of the invention

[0003] In view of this, the present invention provides a semiconductor process chamber structure with a cavity self-cleaning function and a self-cleaning method thereof, which can solve the problem that the dirt accumulated in the reaction chamber of the machine after a long period of time is time-consuming and labor-intensive to treat, and manual cleaning is easy to be not cleaned thoroughly, thereby improving the efficiency of the machine.

[0004] The present invention is achieved through the following technical solutions:

[0005] A semiconductor process chamber structure with a chamber self-cleaning function, in which a CO2 cleaning module is added to the original chamber structure of the reaction chamber;

[0006] The CO2 cleaning module includes: a liquid CO2 source, a gas source, a mixing container, a nozzle, a passage A, a passage B and a control unit;

[0007] The liquid CO2 source is used to provide liquid CO2; the gas source is used to provide compressed air or inert gas;

[0008] The liquid CO2 source and the gas source are connected to the mixing container through passage A respectively; the liquid CO2 is mixed with compressed air or inert gas in the mixing container to form a mixed gas mixed with snowflake-shaped dry ice particles, and the mixed gas is connected to a plurality of nozzles installed in the cavity shell and the pipeline through passage B respectively; the mixed gas is sprayed into the cavity shell and the pipeline respectively through the plurality of nozzles;

[0009] A switch valve is provided on the passage A, and the control unit controls the on and off of passage A by controlling the opening and closing of the switch valve, thereby controlling whether the CO2 cleaning module works or not; a regulating valve is provided on the passage B, and the control unit controls the cleaning flow of the nozzle by controlling the opening of the regulating valve; the control unit also controls the opening and closing of the heater to adjust the temperature of the inner cavity of the chamber shell.

[0010] Furthermore, each nozzle can freely rotate 180° in the horizontal and vertical directions, and the swing rate, rotation angle and position of each nozzle are controlled by the control unit.

[0011] Furthermore, multiple nozzles are respectively installed on the cavity wall of the lower cavity of the cavity shell and at both ends of the butterfly valve of the pipeline. The mixed gas sprayed from the nozzles causes the dirt accumulated in the lower cavity of the cavity shell and at the butterfly valve of the pipeline to fall off, and the fallen dirt is sucked away and discharged by a pump.

[0012] Furthermore, at least four nozzles are arranged in the lower cavity of the cavity shell, two of the four nozzles are grouped together, and the two nozzles in a group are arranged opposite to each other in the vertical direction on the same side of the cavity wall of the cavity shell; at least four nozzles are arranged at the butterfly valve of the pipeline, two of the four nozzles are grouped together, and the two nozzles in a group are arranged opposite to each other in the horizontal direction on the same end of the butterfly valve.

[0013] Furthermore, the inert gas is nitrogen.

[0014] A self-cleaning method for a semiconductor process cavity structure with a cavity self-cleaning function, the self-cleaning method comprising:

[0015] The control unit is preset to start the self-cleaning function after the cavity structure runs X pieces of goods continuously or the machine runs for Y hours: wherein X and Y are both preset values;

[0016] The first step is that when the cavity structure runs X pieces of goods continuously or the machine runs for Y hours, the cavity structure stops running or the machine stops running, and at the same time, the control unit starts the self-cleaning function;

[0017] The second step is to monitor the temperature of the cavity structure and control the heater to heat or not heat through the control unit, so that the inner cavity of the cavity shell is heated and cooled to room temperature;

[0018] In the third step, the control unit turns on the switch valve on the control passage A to start the cleaning function of the CO2 cleaning module to clean the cavity wall of the cavity shell and the dirt accumulated in the pipeline. The control unit controls the cleaning flow of the nozzle by controlling the opening of the regulating valve on the control passage B, and controls the swing rate, rotation angle, and position of each nozzle.

[0019] In the fourth step, after the cleaning is completed, the control unit is used to control the heater to heat or not heat, so that the inner cavity of the cavity shell is heated and cooled to the process temperature, and the cavity structure is run again or the machine is operated again.

[0020] Another semiconductor process chamber structure with chamber self-cleaning function adds a CO2 cleaning module based on the original chamber structure of the reaction chamber;

[0021] The CO2 cleaning module includes: a liquid CO2 source, a gas source, a mixing container, an air jet hole, a passage A, a passage B and a control unit;

[0022] The liquid CO2 source is used to provide liquid CO2; the gas source is used to provide compressed air or inert gas;

[0023] The jet holes are arranged on the inner tube of the support frame, and the plurality of jet holes are evenly distributed on the inner tube. The outlet directions of any two adjacent jet holes are opposite, and the outlet of one jet hole is communicated with the inner cavity of the inner tube. When the silicon wafer, the wafer boat, the support frame and the inner tube on the support frame are raised into or lowered out of the quartz tube, the outlet of another jet hole is communicated with the annular cavity between the quartz tube and the inner tube, so as to realize the cleaning of the inner and outer walls of the inner tube, the inner wall of the quartz tube, the wafer boat and the support frame;

[0024] The liquid CO2 source and the gas source are respectively connected to the mixing container through the passage A; the liquid CO2 is mixed with the compressed air or the inert gas in the mixing container to form a mixed gas mixed with snowflake-shaped dry ice particles, and the mixed gas is respectively connected to a plurality of uniformly distributed jet holes through the passage B; when the silicon wafer, the wafer boat, the support frame and the inner tube on the support frame are raised into or lowered out of the quartz tube, the mixed gas is respectively sprayed into the inner cavity of the inner tube and the annular cavity between the inner tube and the quartz tube through the uniformly distributed jet holes;

[0025] A switch valve is provided on the passage A, and the control unit controls the on and off of the passage A by controlling the opening and closing of the switch valve, thereby controlling whether the CO2 cleaning module works or not; a regulating valve is provided on the passage B, and the control unit controls the cleaning flow of the jet hole by controlling the opening of the regulating valve; the control unit also controls the opening and closing of the heating coil to adjust the temperature of the inner cavity of the quartz tube.

[0026] Furthermore, the air jet hole is in a trumpet-shaped shape.

[0027] Another self-cleaning method for a semiconductor process cavity structure with a cavity self-cleaning function is as follows:

[0028] The control unit is preset to start the self-cleaning function after the cavity structure runs continuously for Z hours: wherein Z is a preset value;

[0029] In the first step, after the cavity structure has been running continuously for Z hours, the cavity structure stops running, and at the same time, the control unit starts the self-cleaning function;

[0030] The second step is to monitor the temperature of the cavity structure and control the heating coil to heat or not heat through the control unit, so that the inner cavity of the quartz tube is heated and cooled to room temperature;

[0031] In the third step, the control unit turns on the switch valve on the control passage A to start the cleaning function of the CO2 cleaning module to clean the inner and outer walls of the inner tube, the inner wall of the quartz tube, the crystal boat and the dirt on the support frame. The control unit controls the cleaning flow of the jet hole by controlling the opening of the regulating valve on the control passage B.

[0032] In the fourth step, after the cleaning is completed, the control unit is used to control the heating coil to heat or not heat, so that the inner cavity of the quartz tube is heated and cooled to the process temperature, and the cavity structure is operated again.

[0033] Beneficial effects:

[0034] (1) The present invention introduces a CO2 cleaning module into the cavity structure and pipeline of the original process cavity. The CO2 cleaning module can provide a mixed gas of snowflake-shaped dry ice particles, which is sprayed into the cavity shell and the pipeline through multiple nozzles respectively. This allows the dirt accumulated in the lower cavity of the cavity shell and the butterfly valve of the pipeline to fall off, and the fallen dirt is pumped out by a pump. This can solve the problem that the treatment of the dirt accumulated in the reaction cavity after a long period of time is time-consuming and labor-intensive, and manual cleaning is easy to be not cleaned thoroughly, thereby improving the efficiency of the machine.

[0035] (2) The present invention adopts a freely rotatable nozzle, which, on the one hand, facilitates the removal of dirt in the lower cavity of the cavity shell and in the dead corners of the pipeline butterfly valve, thereby achieving all-round coverage of the inner wall of the cavity shell. On the other hand, the two nozzles located above and below on the same side can clean each other to prevent dirt from accumulating at the nozzles.

[0036] (3) The multiple nozzles of the present invention are respectively installed on the cavity wall of the lower cavity of the cavity shell and at both ends of the butterfly valve of the pipeline. Dirt is easily accumulated on the cavity wall of the lower cavity of the cavity shell and the butterfly valve of the pipeline. The arrangement of nozzles there can effectively remove the dirt. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is the original cavity structure diagram of the degumming machine;

[0038] Figure 2 This is a cavity structure diagram of Example 1;

[0039] Figure 3 A self-cleaning flow chart of a semiconductor process chamber structure corresponding to Example 1;

[0040] Figure 4 This is the original cavity structure diagram of the vertical furnace tube;

[0041] Figure 5 It is a schematic diagram of the structure of the silicon wafer, the wafer boat and the support frame of the vertical furnace tube rising into the inner tube of the quartz tube;

[0042] Figure 6 This is a cavity structure diagram of Example 3;

[0043] Figure 7 This is a self-cleaning flow chart of the semiconductor process chamber structure corresponding to Example 3.

[0044] Among them, 1-chamber shell, 2-plasma sub-filter plate, 3-ICP source, 4-process gas source, 5-wafer, 6-heater, 7-pipeline, 8-butterfly valve, 9-liquid CO2 source, 10-gas source, 11-mixing container, 12-nozzle, 14-heating coil, 15-silicon wafer, 16-crystal boat, 17-support frame, 18-elevator, 19-inner tube, 20-outer tube, 21-gas supply port, 22-exhaust port. DETAILED DESCRIPTION

[0045] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0046] Embodiment 1:

[0047] This embodiment takes the degumming machine as an example, see the attached Figure 1 The existing original chamber structure of the reaction chamber of the degumming machine includes: a chamber shell 1, a plasma filter plate 2, an ICP (Inductively Coupled Plasma) source 3, a process gas source 4, a wafer 5, a heater 6, a pipeline 7, a pump and a butterfly valve 8;

[0048] The plasma sub-filter plate 2 is installed in the chamber shell 1, dividing the inner cavity of the chamber shell 1 into two parts, namely an upper cavity and a lower cavity;

[0049] The heater 6 and the wafer 5 are both located in the lower chamber of the chamber shell 1, and the heater 6 is installed at the bottom of the chamber shell 1, and the wafer 5 is installed on the heater 6, and the wafer 5 is opposite to the plasma sub-filter plate 2;

[0050] The ICP source 3 and the process gas source 4 are both introduced into the upper cavity of the cavity shell 1 through the top of the cavity shell 1; the ICP source 3 is an inductively coupled plasma source;

[0051] A pipeline 7 communicating with the inner cavity of the chamber shell 1 is installed at the bottom of the chamber shell 1, and a butterfly valve 8 and a pump are installed on the pipeline 7. Compared with the pump, the butterfly valve 8 is located closer to the bottom of the chamber shell 1; by controlling the opening of the butterfly valve 8, the pressure of the inner cavity of the chamber shell 1 can be controlled;

[0052] When the cavity structure is running, the plasma reactants are excited by the ICP source 3 and the process gas source 4 to remove the photoresist on the surface of the wafer 5, and the exhaust gas is pumped out by the pump on the pipeline 7. During the running process, dirt is easily accumulated on the inner wall of the cavity shell 1, the internal parts of the cavity shell 1, the corners of the pipeline 7, and the butterfly valve 8 and other valves.

[0053] Therefore, this embodiment provides a semiconductor process chamber structure with a chamber self-cleaning function, see the attached Figure 2 , a CO2 cleaning module is added to the original chamber structure of the reaction chamber of the degumming machine;

[0054] The CO2 cleaning module includes: a liquid CO2 source 9, a gas source 10, a mixing container 11, a nozzle 12, a passage A, a passage B and a control unit;

[0055] The liquid CO2 source 9 is used to provide liquid CO2; the gas source 10 is used to provide compressed air / N2 or other inert gases;

[0056] The liquid CO2 source 9 and the gas source 10 are respectively connected to the mixing container 11 through the passage A; the liquid CO2 and the compressed air / N2 or other inert gas are mixed in the mixing container 11 to form a mixed gas mixed with snowflake-shaped dry ice particles, and the mixed gas is respectively connected to the multiple nozzles 12 installed in the chamber shell 1 and the pipeline 7 through the passage B; the mixed gas is sprayed into the chamber shell 1 and the pipeline 7 through the multiple nozzles 12;

[0057] Among them, a plurality of nozzles 12 are respectively installed on the cavity wall of the lower cavity of the cavity shell 1 and at both ends of the butterfly valve 8 of the pipeline 7. The mixed gas sprayed from the nozzles 12 causes the dirt accumulated in the lower cavity of the cavity shell 1 and the butterfly valve 8 of the pipeline 7 to fall off, and the fallen dirt is pumped away and discharged by the pump;

[0058] The passage A is provided with a switch valve, and the control unit controls the on and off of the passage A by controlling the opening and closing of the switch valve, thereby controlling whether the CO2 cleaning module works or not; the passage B is provided with a regulating valve, and the control unit can control the cleaning flow of the nozzle 12 by controlling the opening of the regulating valve; the control unit also controls the opening and closing of the heater 6 to adjust the temperature of the inner cavity of the chamber shell 1;

[0059] Further, in this embodiment, at least four nozzles 12 are arranged in the lower cavity of the cavity shell 1, and two of the four nozzles 12 form a group, and the two nozzles 12 in one group are arranged on the same side of the cavity wall of the cavity shell 1 in the vertical direction. In this embodiment, at least four nozzles 12 are arranged at the butterfly valve 8 of the pipeline 7, and two of the four nozzles 12 form a group, and the two nozzles 12 in one group are arranged on the same end of the butterfly valve 8 in the horizontal direction.

[0060] Furthermore, each nozzle 12 of the present embodiment can freely rotate 180° in the horizontal and vertical directions. On the one hand, the freely rotatable nozzle 12 is convenient for removing dirt in the lower chamber of the chamber shell 1 and in the dead corners of the butterfly valve 8 of the pipeline 7. On the other hand, the two nozzles 12 located above and below on the same side can clean each other to prevent dirt from accumulating at the nozzles 12; wherein the swing rate, rotation angle, and position of each nozzle 12 can be controlled by the control unit.

[0061] The cleaning mechanism of the mixed gas to remove the dirt accumulated in the lower cavity of the cavity 1 shell and the butterfly valve 8 of the pipeline 7 is as follows: 1) The mixed gas of the snowflake-shaped dry ice particles quickly sublimates after hitting the dirt, and the dirt is suddenly cooled, shrunk, brittle, and then peeled off and washed away; 2) After the mixed gas of the snowflake-shaped dry ice particles penetrates into the gaps of the dirt, it sublimates within one thousandth of a second, and the volume instantly expands 600 to 800 times, peeling the dirt off the surface of the object; 3) Different materials have different thermal expansion coefficients, and the temperature of the mixed gas of the snowflake-shaped dry ice particles is low (-78.5°C), and after contacting the dirt, the dirt cracks and peels off at low temperature. The above three situations can exist at the same time.

[0062] Embodiment 2:

[0063] This embodiment provides a self-cleaning method for a semiconductor process cavity structure with a cavity self-cleaning function based on Embodiment 1. Figure 3 , the self-purification method is:

[0064] The control unit is preset to start the self-cleaning function after the cavity structure runs X pieces of goods continuously or the machine runs for Y hours: wherein X and Y are both preset values;

[0065] The first step is that when the cavity structure runs X pieces of goods continuously or the machine runs for Y hours, the cavity structure stops running or the machine stops running, and at the same time, the control unit starts the self-cleaning function;

[0066] In the second step, by monitoring the temperature of the cavity structure, the control unit controls the heater 6 to heat or not heat, so that the inner cavity of the cavity shell 1 is heated and cooled to a certain temperature, such as room temperature;

[0067] In the third step, the control unit turns on the switch valve on the control passage A to start the cleaning function of the CO2 cleaning module to clean the cavity wall of the cavity shell 1 and the dirt accumulated in the pipeline 7. The control unit controls the cleaning flow of the nozzle 12 by controlling the opening of the regulating valve on the control passage B, and controls the swing rate, rotation angle, and position of each nozzle 12, so as to facilitate the cleaning of the cavity wall of the cavity shell 1 and the dirt at the dead corner of the pipeline 7;

[0068] In the fourth step, after the cleaning is completed, the control unit controls the heater 6 to heat or not heat again, so that the inner cavity of the cavity shell 1 is heated and cooled to the process temperature, and the cavity structure is run again or the machine is operated again.

[0069] Embodiment 3:

[0070] This embodiment takes a vertical furnace tube as an example. Figure 4-Figure 5 The existing original chamber structure of the reaction chamber of the vertical furnace tube includes: a quartz tube, a heating coil 14, a silicon wafer 15, a wafer boat 16, a support frame 17 and an elevator 18;

[0071] The quartz tube is made of high-purity quartz, the structure of the quartz tube is hollow in the center, and can quickly generate heat through resistance heating, and the bottom of the quartz tube is open; the quartz tube is equivalent to the chamber shell 1 of Example 1;

[0072] The heating coil 14 is surrounded by the quartz tube and is composed of a resistance wire, and is used to heat the inner cavity of the quartz tube;

[0073] The silicon wafer 15 is equivalent to the wafer 5 of Example 1; the silicon wafer 15 is placed on a wafer boat 16, the wafer boat 16 is mounted on a support frame 17, and the support frame 17 is mounted on an elevator 18; the elevator 18 is used to lift the silicon wafer 15, the wafer boat 16 and the support frame 17 into or out of the quartz tube to realize automatic loading and unloading of the silicon wafer 15; the silicon wafer 15 is heated and oxidized in the quartz tube; the wafer boat 16 is used to ensure that the silicon wafer 15 remains stable during the process; the support frame 17 is made of high temperature resistant material , and an inner tube 19 is provided on the support frame 17, and the silicon wafer 15 and the wafer boat 16 are both located in the inner tube 19; when the silicon wafer 15, the wafer boat 16 and the support frame 17 are lifted into the quartz tube, the inner tube 19 and the quartz tube form a double-layer tube structure, and the quartz tube serves as the outer tube 20 of the double-layer tube structure; the inner tube 19 is coaxially installed in the outer tube 20, and an annular cavity is left between the two, and at this time, the support frame 17 closes the bottom opening of the quartz tube, so that the inner cavity of the quartz tube forms a closed chamber;

[0074] The support frame 17 is also provided with a gas supply port 21 and an exhaust port 22. The gas supply port 21 is used to transport oxygen or other gases into the inner tube 19. After the reaction is completed, the waste gas generated flows through the annular cavity between the inner tube 19 and the outer tube 20 and is discharged from the outside of the quartz tube through the exhaust port 22.

[0075] When the cavity structure is working, the silicon wafer 15 is heated and oxidized in the quartz tube, and dirt is easily accumulated on the inner wall of the quartz tube (ie, the inner wall of the outer tube 20 ), the inner and outer walls of the inner tube 19 , the wafer boat 16 and the support frame 17 .

[0076] Therefore, this embodiment provides a semiconductor process chamber structure with a chamber self-cleaning function, see the attached Figure 6 , a CO2 cleaning module is added to the original chamber structure of the vertical furnace tube reaction chamber;

[0077] The CO2 cleaning module comprises: a liquid CO2 source 9, a gas source 10, a mixing container 11, an air jet hole, a passage A, a passage B and a control unit;

[0078] The liquid CO2 source 9 is used to provide liquid CO2; the gas source 10 is used to provide compressed air / N2 or other inert gases;

[0079] The jet holes are arranged on the inner tube 19 of the support frame 17, and a plurality of jet holes are evenly distributed on the inner tube 19, and the outlet directions of any two adjacent jet holes are opposite, the outlet of one jet hole is communicated with the inner cavity of the inner tube 19, and the outlet of the other jet hole is communicated with the annular cavity between the inner tube 19 and the outer tube 20, so as to realize the cleaning of the inner and outer walls of the inner tube 19, the inner wall of the outer tube 20, the wafer boat 16 and the support frame 17; in one embodiment, the jet hole is in the shape of a bell mouth; in another embodiment, in the thin film deposition, such as the silicon nitride deposition process, a small amount of inert gas can be introduced into the jet hole to form a local gas barrier at the jet hole, which does not affect the process and can also prevent the reaction gas from passing through the jet hole into the CO2 cleaning module for reaction;

[0080] The liquid CO2 source 9 and the gas source 10 are connected to the mixing container 11 through the passage A respectively; the liquid CO2 and the compressed air / N2 or other inert gas are mixed in the mixing container 11 to form a mixed gas mixed with snowflake-shaped dry ice particles, and the mixed gas is connected to a plurality of uniformly distributed jet holes one by one through the passage B respectively; when the silicon wafer 15, the wafer boat 16, the support frame 17 and the inner tube 19 on the support frame 17 are raised into or lowered out of the quartz tube (i.e., the outer tube 20), the mixed gas is sprayed into the inner cavity of the inner tube 19 and between the inner tube 19 and the outer tube 20 through the uniformly distributed jet holes respectively. annular cavity; in this embodiment, one end of the passage B is connected to the mixing container 11, and the other end is divided into two branches, which pass through and are fixed on the support frame 17 respectively, one of which is located on the inner side of the inner tube 19, and a plurality of connecting structures are provided on the branch to connect with the jet holes on the inner tube 19, so that the outlet of the jet holes communicates with the annular cavity between the inner tube 19 and the outer tube 20, and the other branch is located between the outer side of the inner tube 19 and the inner side of the outer tube 20, and a plurality of connecting structures are provided on the branch to connect with the jet holes on the inner tube 19, so that the outlet of the jet holes communicates with the inner cavity of the inner tube 19;

[0081] The passage A is provided with a switch valve, and the control unit controls the opening and closing of the passage A by controlling the opening and closing of the switch valve, thereby controlling the operation of the CO2 cleaning module; the passage B is provided with a regulating valve, and the control unit can control the cleaning flow of the jet hole by controlling the opening of the regulating valve; the control unit also controls the opening and closing of the heating coil 14 to adjust the temperature of the inner cavity of the quartz tube;

[0082] The cleaning mechanism of the mixed gas to remove the dirt accumulated on the quartz tube, the crystal boat 16 and the support frame 17 is as follows: 1) The mixed gas of the snowflake-shaped dry ice particles quickly sublimates after hitting the dirt, and the dirt suddenly cools, shrinks, becomes brittle, and then peels off and is washed away; 2) After the mixed gas of the snowflake-shaped dry ice particles penetrates into the gaps of the dirt, it sublimates within one thousandth of a second, and the volume instantly expands 600 to 800 times, peeling the dirt off the surface of the object; 3) Different materials have different thermal expansion coefficients, and the temperature of the mixed gas of the snowflake-shaped dry ice particles is low (-78.5°C), and after contacting the dirt, the dirt cracks and peels off at low temperature. The above three situations can exist at the same time.

[0083] Embodiment 4:

[0084] This embodiment provides a self-cleaning method for a semiconductor process cavity structure with a cavity self-cleaning function based on Embodiment 2. Figure 7 , the self-purification method is:

[0085] The control unit is preset to start the self-cleaning function after the cavity structure runs continuously for Z hours: wherein Z is a preset value;

[0086] In the first step, after the cavity structure has been running continuously for Z hours, the cavity structure stops running, and at the same time, the control unit starts the self-cleaning function;

[0087] In the second step, by monitoring the temperature of the cavity structure, the control unit controls the heating coil 14 to heat or not heat, so that the inner cavity of the quartz tube is heated and cooled to a certain temperature, such as room temperature;

[0088] In the third step, the control unit turns on the switch valve on the control passage A to start the cleaning function of the CO2 cleaning module to clean the inner and outer walls of the inner tube 19, the inner wall of the quartz tube, the crystal boat 16 and the dirt on the support frame 17, wherein the control unit controls the cleaning flow of the jet hole by controlling the opening of the regulating valve on the control passage B;

[0089] In the fourth step, after the cleaning is completed, the control unit controls the heating coil 14 to heat or not heat, so that the inner cavity of the quartz tube is heated and cooled to the process temperature, and the cavity structure is operated again.

[0090] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A semiconductor process chamber structure with a chamber self-cleaning function, characterized in that: A CO2 cleaning module is added to the original chamber structure of the reaction chamber; The CO2 cleaning module includes: a liquid CO2 source, a gas source, a mixing container, a nozzle, a passage A, a passage B and a control unit; The liquid CO2 source is used to provide liquid CO2; the gas source is used to provide compressed air or inert gas; The liquid CO2 source and the gas source are respectively connected to the mixing container through passage A; the liquid CO2 is mixed with compressed air or inert gas in the mixing container to form a mixed gas mixed with snowflake-shaped dry ice particles, and the mixed gas is connected to a plurality of nozzles installed in the chamber shell and the pipeline through passage B; the mixed gas is sprayed into the chamber shell and the pipeline through the plurality of nozzles; a butterfly valve and a pump are installed on the pipeline, and the plurality of nozzles are respectively installed on the cavity wall of the lower cavity of the chamber shell and at both ends of the position where the butterfly valve of the pipeline is located, and the mixed gas sprayed from the nozzle causes the dirt accumulated in the lower cavity of the chamber shell and the butterfly valve of the pipeline to fall off, and the fallen dirt is sucked away and discharged by the pump; A switch valve is provided on the passage A, and the control unit controls the on and off of passage A by controlling the opening and closing of the switch valve, thereby controlling whether the CO2 cleaning module works or not; a regulating valve is provided on the passage B, and the control unit controls the cleaning flow of the nozzle by controlling the opening of the regulating valve; the control unit also controls the opening and closing of the heater to adjust the temperature of the inner cavity of the chamber shell.

2. A semiconductor process chamber structure with chamber self-cleaning function as claimed in claim 1, characterized in that: Each nozzle can rotate freely 180° in horizontal and vertical directions, and the swing rate, rotation angle and position of each nozzle are controlled by the control unit.

3. A semiconductor process chamber structure with chamber self-cleaning function as claimed in claim 1, characterized in that: At least four nozzles are arranged in the lower cavity of the cavity shell, two of the four nozzles form a group, and the two nozzles in one group are arranged on the same side of the cavity shell wall in the vertical direction; at least four nozzles are arranged at the butterfly valve of the pipeline, two of the four nozzles form a group, and the two nozzles in one group are arranged on the same end of the butterfly valve in the horizontal direction.

4. A semiconductor process chamber structure with chamber self-cleaning function as claimed in claim 1, characterized in that: The inert gas is nitrogen.

5. A self-cleaning method for a semiconductor process cavity structure with a cavity self-cleaning function, based on the cavity structure of any one of claims 1 to 4, characterized in that: The self-purification method is: The control unit is preset to start the self-cleaning function after the cavity structure runs X pieces of goods continuously or the machine runs for Y hours: wherein X and Y are both preset values; The first step is that when the cavity structure runs X pieces of goods continuously or the machine runs for Y hours, the cavity structure stops running or the machine stops running, and at the same time, the control unit starts the self-cleaning function; The second step is to monitor the temperature of the cavity structure and control the heater to heat or not heat through the control unit, so that the inner cavity of the cavity shell is heated and cooled to room temperature; In the third step, the control unit turns on the switch valve on the control passage A to start the cleaning function of the CO2 cleaning module to clean the cavity wall of the cavity shell and the dirt accumulated in the pipeline. The control unit controls the cleaning flow of the nozzle by controlling the opening of the regulating valve on the control passage B, and controls the swing rate, rotation angle, and position of each nozzle. In the fourth step, after the cleaning is completed, the control unit is used to control the heater to heat or not heat, so that the inner cavity of the cavity shell is heated and cooled to the process temperature, and the cavity structure is run again or the machine is operated again.

6. A semiconductor process chamber structure with a chamber self-cleaning function, characterized in that: A CO2 cleaning module is added to the original chamber structure of the reaction chamber; The CO2 cleaning module includes: a liquid CO2 source, a gas source, a mixing container, an air jet hole, a passage A, a passage B and a control unit; The liquid CO2 source is used to provide liquid CO2; the gas source is used to provide compressed air or inert gas; The jet holes are arranged on the inner tube of the support frame, and the plurality of jet holes are evenly distributed on the inner tube. The outlet directions of any two adjacent jet holes are opposite, and the outlet of one jet hole is communicated with the inner cavity of the inner tube. When the silicon wafer, the wafer boat, the support frame and the inner tube on the support frame are raised into or lowered out of the quartz tube, the outlet of another jet hole is communicated with the annular cavity between the quartz tube and the inner tube, so as to realize the cleaning of the inner and outer walls of the inner tube, the inner wall of the quartz tube, the wafer boat and the support frame; The liquid CO2 source and the gas source are respectively connected to the mixing container through the passage A; the liquid CO2 is mixed with the compressed air or the inert gas in the mixing container to form a mixed gas mixed with snowflake-shaped dry ice particles, and the mixed gas is respectively connected to a plurality of uniformly distributed jet holes through the passage B; when the silicon wafer, the wafer boat, the support frame and the inner tube on the support frame are raised into or lowered out of the quartz tube, the mixed gas is respectively sprayed into the inner cavity of the inner tube and the annular cavity between the inner tube and the quartz tube through the uniformly distributed jet holes; A switch valve is provided on the passage A, and the control unit controls the on and off of the passage A by controlling the opening and closing of the switch valve, thereby controlling whether the CO2 cleaning module works or not; a regulating valve is provided on the passage B, and the control unit controls the cleaning flow of the jet hole by controlling the opening of the regulating valve; the control unit also controls the opening and closing of the heating coil to adjust the temperature of the inner cavity of the quartz tube.

7. A semiconductor process chamber structure with chamber self-cleaning function as claimed in claim 6, characterized in that: The jet hole is in a trumpet shape.

8. The semiconductor process chamber structure with chamber self-cleaning function according to claim 6, characterized in that: The inert gas is nitrogen.

9. A self-cleaning method for a semiconductor process cavity structure with cavity self-cleaning function, based on the cavity structure of any one of claims 6 to 8, characterized in that: The self-purification method is: The control unit is preset to start the self-cleaning function after the cavity structure runs continuously for Z hours: wherein Z is a preset value; In the first step, after the cavity structure has been running continuously for Z hours, the cavity structure stops running, and at the same time, the control unit starts the self-cleaning function; The second step is to monitor the temperature of the cavity structure and control the heating coil to heat or not heat through the control unit, so that the inner cavity of the quartz tube is heated and cooled to room temperature; In the third step, the control unit turns on the switch valve on the control passage A to start the cleaning function of the CO2 cleaning module to clean the inner and outer walls of the inner tube, the inner wall of the quartz tube, the crystal boat and the dirt on the support frame. The control unit controls the cleaning flow of the jet hole by controlling the opening of the regulating valve on the control passage B. In the fourth step, after the cleaning is completed, the control unit is used to control the heating coil to heat or not heat, so that the inner cavity of the quartz tube is heated and cooled to the process temperature, and the cavity structure is operated again.

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