Cleaning system for silicon nitride etching bushing

Abstract

The invention relates to a cleaning system for a silicon nitride etching bushing. Comprising a first main body, a second main body rotationally connected with the first main body, a cleaning pipeline composed of a main pipeline arranged in the first main body and a purging pipeline arranged in the second main body, a plasma generator connected with the main pipeline and a recovery channel penetrating through the first main body and the second main body. The axis of the recovery channel coincides with the axis of the main pipeline, the recovery channel is located in the main pipeline, the multiple purging pipelines are evenly arranged around the axis of the recovery channel, the first ends of the purging pipelines communicate with the main pipeline, and the second ends of the purging pipelines incline in the direction close to the recovery channel. According to the cleaning system of the silicon nitride etching bushing, photoresist on a complex pattern is completely removed through targeted cleaning of the areas on the base material, meanwhile, cleaning parameter adjustment of all the areas is achieved through movement and airflow pressure adjustment, and structural damage possibly caused by long-time exposure of the base material is avoided.

Description

Technical Field

[0001] The present application relates to the technical field of chip production equipment, and in particular to a cleaning system for a silicon nitride etching leak plate. Background Art

[0002] During the processing of silicon nitride etching leak board, photoresist is needed to assist production, and then the photoresist is stripped after production is completed. There are two etching methods: dry etching and wet etching. Wet etching is achieved by the corrosiveness of the solution. This method is anisotropic and requires a large amount of water and cleaning solvents. It is gradually being replaced by dry etching.

[0003] Dry etching uses light to complete etching and is isotropic. Based on dry etching, the photoresist removal process enters the dry removal stage. Since dry removal is also isotropic, the continuity of the isotropy of dry etching can be ensured.

[0004] Currently, a mainstream dry etching method is to place the substrate in a vacuum environment, inject an appropriate amount of oxygen and then ionize it. The generated plasma reacts with the photoresist under the drive of the electric field. This process has high requirements on vacuum degree, electric field strength and oxygen flow rate, and is time-consuming.

[0005] One reason why it is time-consuming is the non-planarity of the design pattern, which requires increasing the time to ensure the complete removal of the photoresist. However, the uneven distribution of the photoresist will cause the substrate to be exposed for a long time, posing a risk of damage. Summary of the invention

[0006] The present application provides a cleaning system for a silicon nitride etching leak plate, which can achieve complete removal of photoresist on complex patterns by targeted cleaning of areas on a substrate, and can also achieve adjustment of cleaning parameters for each area by movement and airflow pressure adjustment, thereby avoiding structural damage that may be caused by long-term exposure of the substrate.

[0007] The above-mentioned purpose of the present application is achieved through the following technical solutions:

[0008] The present application provides a cleaning system for a silicon nitride etching leak plate, comprising:

[0009] A first body and a second body rotatably connected to the first body;

[0010] A cleaning pipeline, including a main pipeline arranged in the first body and a purge pipeline arranged in the second body, wherein the number of the purge pipelines is multiple and all are connected to the main pipeline;

[0011] A plasma generator is connected to the main pipeline;

[0012] A recovery channel, which runs through the first body and the second body;

[0013] Wherein, the axis of the recovery channel coincides with the axis of the main pipeline and the recovery channel is located inside the main pipeline;

[0014] A plurality of purge pipes are evenly arranged around the axis of the recovery channel;

[0015] The first end of the purge pipeline is communicated with the main pipeline, and the second end of the purge pipeline is inclined toward a direction close to the recovery channel.

[0016] In a possible implementation of the present application, the area of ​​the enclosed region of the purge channel on the photoresist layer is one half to two thirds of the area of ​​the enclosed region of the purge channel.

[0017] In a possible implementation of the present application, a windshield curtain wall is provided on the second body, and the coverage area of ​​the purge pipeline is located inside the coverage area of ​​the windshield curtain wall;

[0018] The windshield curtain wall is tilted away from the recovery channel.

[0019] In a possible implementation of the present application, the windshield curtain wall extracts gas from the surrounding environment.

[0020] In a possible implementation of the present application, the windshield curtain wall includes:

[0021] Fan;

[0022] an air duct, arranged on the second main body;

[0023] The two ends of the flexible pipe are respectively connected to the fan and the air duct.

[0024] In a possible implementation of the present application, a plasma generator uses an external gas to generate plasma.

[0025] In a possible implementation of the present application, an arc-shaped guide body is provided on the distal end of the second main body, the recovery channel is located on the inner side of the arc-shaped guide body, and the second end of the purge pipe is located on the outer side of the arc-shaped guide body.

[0026] In a possible implementation of the present application, the axis of the second end of the purge pipe is parallel to a tangent line of the second end of the purge pipe at the location of the arc-shaped guide body.

[0027] In a possible implementation of the present application, an arc-shaped guide ring is provided on the arc-shaped guide body;

[0028] The second end of the purge pipeline is located between the arc-shaped guide body and the arc-shaped guide ring;

[0029] In the gas flow direction, the distance between the outer wall of the arc-shaped guide body and the inner wall of the arc-shaped guide ring is equal everywhere. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of an existing photoresist removal method.

[0031] Figure 2 It is a structural schematic diagram of a cleaning system provided in this application.

[0032] Figure 3 It is a structural schematic diagram of a first body, a second body and their interior provided by the present application.

[0033] Figure 4 This is a schematic diagram of a rotational connection between a first body and a second body provided in the present application.

[0034] Figure 5 This is a schematic diagram of the flow path of a cleaning gas provided in this application.

[0035] Figure 6 This is a schematic diagram of a cleaning path on a substrate provided in the present application.

[0036] Figure 7 The present invention is a comparative schematic diagram of existing photoresist removal.

[0037] Figure 8 It is a comparative schematic diagram of photoresist removal of the cleaning system provided in this application.

[0038] In the figure, 2, cleaning pipeline, 3, plasma generator, 4, recovery channel, 11, first body, 12, second body, 21, main pipeline, 22, purge pipeline, 23, arc guide body, 24, arc guide ring, 51, fan, 52, air duct, 53, flexible pipeline. DETAILED DESCRIPTION

[0039] In order to more clearly understand the technical solution in this application, the relevant technology is first introduced.

[0040] See also Figure 1 The substrate in the figure (chip or intermediate to be cleaned) is placed in a vacuum box, ionized in the box, and plasma is generated. An electric field is set in the vacuum box, and the plasma flows from top to bottom ( Figure 1 The photoresist moves (arrows in the figure), contacts and reacts with the photoresist on the substrate, causing the photoresist to decompose.

[0041] In this method, the contact time between the substrate and the plasma is equal, and in order to realize the photoresist on complex patterns ( Figure 2 To achieve peeling of the substrate (as shown), it is also necessary to increase the exposure time of the substrate.

[0042] The technical solution in this application is further described in detail below in conjunction with the accompanying drawings.

[0043] The present application discloses a cleaning system for a silicon nitride etching leak plate. In some examples, the cleaning system for a silicon nitride etching leak plate disclosed in the present application includes a first body 11 , a second body 12 , a cleaning pipeline 2 , a plasma generator 3 and a recovery channel 4 .

[0044] First of all, please refer to Figure 2 The cleaning system of the silicon nitride etching leak plate disclosed in the present application is installed in a cleaning box, and a rotating table is arranged at the bottom of the cleaning box, and the substrate is placed on the rotating table. The cleaning system of the silicon nitride etching leak plate disclosed in the present application is located on the top surface of the cleaning box.

[0045] In addition, a linear lifting module and a horizontal moving module are required to realize movement. The linear lifting module is installed on the top surface of the cleaning box, and the horizontal moving module is installed on the linear lifting module. The linear lifting module and the horizontal moving module are used to realize the vertical lifting and horizontal translation of the cleaning system for silicon nitride etching leak plate disclosed in this application.

[0046] At this time, by rotating the contact turntable, full coverage of the substrate can be achieved.

[0047] The first body 11 and the second body 12 are connected in a rotating manner. Figure 4 As shown, the bearing is installed at the parting surface between the first body 11 and the second body 12 .

[0048] In some possible implementations, a motor is installed on the first body 11, and the motor is used to drive the second body 12 to rotate at a fixed speed.

[0049] The cleaning pipeline 2 is divided into two parts, namely a main pipeline 21 located in the first main body 11 and a purge pipeline 22 located in the second main body 12. There are multiple purge pipelines 22 and they are all connected to the main pipeline 21. These purge pipelines 22 are evenly arranged around the axis of the recovery channel 4.

[0050] pass Figure 4 It can be seen that there is a buffer area below the main pipeline 21, and the purge pipeline 22 is connected to the buffer area.

[0051] The plasma generator 3 is connected to the main pipe 21 , and the plasma generator 3 can be installed on the first main body 11 or on the top surface of the cleaning box.

[0052] When the plasma generator 3 is installed on the first body 11, oxygen needs to be introduced from outside the cleaning box with the help of a hose; when the plasma generator 3 is installed on the top surface of the cleaning box, oxygen is introduced from outside the cleaning box and connected to the main pipeline 21 using a hose.

[0053] The plasma generator 3 generates plasma using an external gas.

[0054] The recovery channel 4 runs through the first body 11 and the second body 12, and its function is to recover the gas in contact with the substrate. The axis of the recovery channel 4 coincides with the axis of the main pipeline 21 and the recovery channel 4 is located inside the main pipeline 21, so that the recovery channel 4 can be located at the center of the first body 11 and the second body 12.

[0055] In conjunction with a specific cleaning process, the linear lifting module and the horizontal moving module move the cleaning system of the silicon nitride etching leak plate disclosed in the present application to a cleaning position above the substrate, and at the same time inject inert gas into the interior of the cleaning box to create an inert gas environment.

[0056] Then the plasma generator 3 is started, and the gas delivered to the inside of the plasma generator 3 is oxygen. The ionized oxygen generates plasma, which is then delivered to the main pipeline 21 and then delivered to each purge pipeline 22. After the oxygen containing plasma (hereinafter referred to as cleaning gas) is ejected from the purge pipeline 22, it contacts the photoresist on the substrate and decomposes the photoresist. The flow path of the cleaning gas is as follows: Figure 5 shown.

[0057] In the above process, the horizontal moving module and the rotating table cooperate to realize the removal of photoresist at various locations on the substrate. One advantage of this method is that it can adapt to substrates of different diameters and can also concentrate the cleaning gas, so that the cleaning path of the substrate can be controlled. Figure 6 shown.

[0058] After the cleaning gas ejected from the purge pipe 22 contacts the substrate, it will leave the cleaning box through the recovery channel 4. After the cleaning gas contacts the photoresist, the main product is gas, and the cleaning gas and the gas generated by the decomposition of the photoresist can leave the cleaning box through the recovery channel 4.

[0059] The cleaning effect comparison is Figure 7 and Figure 8 As shown, in Figure 7 It is obvious that the photoresist removal in the vertical area is difficult, but Figure 8 This problem does not exist in .

[0060] In addition, a certain amount of soluble substances will be produced during the decomposition process of the photoresist, and these soluble substances can be removed by adding water to the cleaning gas.

[0061] As for the shape of the purge pipe 22, the first end of the purge pipe 22 needs to be connected to the main pipe 21, and the second end needs to be inclined toward the recovery channel 4. The purpose is to make the cleaning gas flow toward the recovery channel 4, so that it can quickly leave the cleaning box after contacting the substrate.

[0062] This is because the cleaning system provided in the present application may produce photoresist debris compared to other cleaning methods. If these debris fall to other locations on the substrate, the photoresist thickness at other locations on the substrate will change, resulting in incomplete cleaning.

[0063] In some possible implementations, the area of ​​the enclosed region of the purge channel 22 on the photoresist layer is one half to two thirds of the area of ​​the enclosed region of the purge channel 22 .

[0064] In some examples, a windshield curtain wall 5 is provided on the second body 12, the coverage area of ​​the purge pipe 22 is located inside the coverage area of ​​the windshield curtain wall 5, and the windshield curtain wall 5 is inclined in a direction away from the recovery channel 4. The function of the windshield curtain wall 5 is to form a barrier around the purge pipe 22 to prevent the generated photoresist debris from falling to other positions on the substrate.

[0065] Furthermore, the windshield curtain wall 5 extracts gas from the surrounding environment, that is, directly uses the inert gas in the surrounding environment.

[0066] For some examples, see Figure 2 The windshield curtain wall 5 includes a fan 51, an air duct 52 and a flexible pipe 53. The fan 51 can be installed on the top surface of the cleaning box, the air duct 52 is located on the second main body 12, and both ends of the flexible pipe 53 are connected to the fan 51 and the air duct 52 respectively.

[0067] The fan 51 directly extracts inert gas from the cleaning box and delivers it into the air duct 52 through the flexible pipe 53. The inert gas is ejected from the air duct 52 and directly returns to the cleaning box.

[0068] For some examples, see Figure 3 An arc-shaped guide body 23 is provided at the distal end of the second main body 12 . The positional relationship between the arc-shaped guide body 23 , the recovery channel 4 and the purge pipe 22 is as follows: the recovery channel 4 is located on the inner side of the arc-shaped guide body 23 , and the second end of the purge pipe 22 is located on the outer side of the arc-shaped guide body 23 .

[0069] The arc-shaped guide body 23 has the following functions: guiding the flow direction of the cleaning gas, limiting the flow range of the cleaning gas and making the cleaning gas more concentrated.

[0070] In addition, when the arc-shaped guide 23 moves, the gap between it and the substrate will change. When non-planar cleaning is performed, the width of the gap between the arc-shaped guide 23 and the substrate can be appropriately reduced to improve the cleaning effect.

[0071] Furthermore, the axis of the second end of the purge pipe 22 is parallel to the tangent line of the second end of the purge pipe 22 at the location of the arc-shaped guide body 23 .

[0072] Furthermore, an arc-shaped guide ring 24 is provided on the arc-shaped guide body 23, and the positional relationship between the arc-shaped guide ring 24 and the second end of the purge pipe 22 and the arc-shaped guide body 23 is that the second end of the purge pipe 22 is located between the arc-shaped guide body 23 and the arc-shaped guide ring 24.

[0073] In addition, in the gas flow direction, the distance between the outer wall of the arc-shaped guide body 23 and the inner wall of the arc-shaped guide ring 24 is equal everywhere.

[0074] The arc-shaped guide body 23 cooperates with the arc-shaped guide ring 24 to make the flow direction and flow range of the cleaning gas more controllable, and can also make the cleaning gas more concentrated, reducing the waste caused by overflow.

[0075] The embodiments of this specific implementation method are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore, all equivalent changes made based on the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A cleaning system for a silicon nitride etching leak plate, characterized in that: include: A first body (11) and a second body (12) rotatably connected to the first body (11); A cleaning pipeline (2) comprises a main pipeline (21) arranged in the first body (11) and a purge pipeline (22) arranged in the second body (12); the purge pipelines (22) are multiple in number and are all connected to the main pipeline (21); A plasma generator (3) connected to the main pipeline (21); A recovery channel (4) passing through the first body (11) and the second body (12); The axis of the recovery channel (4) coincides with the axis of the main pipeline (21), and the recovery channel (4) is located inside the main pipeline (21); A plurality of purge pipes (22) are evenly arranged around the axis of the recovery channel (4); The first end of the purge pipe (22) is in communication with the main pipe (21), and the second end of the purge pipe (22) is inclined in a direction close to the recovery channel (4).

2. The cleaning system for silicon nitride etching bushing according to claim 1, characterized in that: The area of ​​the enclosed region of the purge channel (22) on the photoresist layer is one half to two thirds of the area of ​​the enclosed region of the purge channel (22).

3. The cleaning system for silicon nitride etching bushing according to claim 1 or 2, characterized in that: A windshield curtain wall (5) is provided on the second main body (12), and the coverage area of ​​the purge pipe (22) is located inside the coverage area of ​​the windshield curtain wall (5); The windshield curtain wall (5) is inclined in a direction away from the recovery channel (4).

4. The cleaning system for silicon nitride etching leak plate according to claim 3, characterized in that: The windshield curtain wall (5) extracts gas from the surrounding environment.

5. The cleaning system for silicon nitride etching bushing according to claim 3, characterized in that: The windshield curtain wall (5) comprises: Fan (51); An air duct (52) is provided on the second body (12); The flexible pipe (53) has two ends connected to the fan (51) and the air duct (52) respectively.

6. The cleaning system for silicon nitride etching leak plate according to claim 4, characterized in that: The plasma generator (3) generates plasma using an external gas.

7. The cleaning system for silicon nitride etching bushing according to claim 1, characterized in that: An arc-shaped guide body (23) is provided at the far end of the second main body (12), the recovery channel (4) is located on the inner side of the arc-shaped guide body (23), and the second end of the purge pipe (22) is located on the outer side of the arc-shaped guide body (23).

8. The cleaning system for silicon nitride etching bushing according to claim 7, characterized in that: The axis of the second end of the purge pipe (22) is parallel to the tangent line of the second end of the purge pipe (22) at the location of the arc-shaped guide body (23).

9. The cleaning system for silicon nitride etching bushing according to claim 8, characterized in that: An arc-shaped guide ring (24) is provided on the arc-shaped guide body (23); The second end of the purge pipe (22) is located between the arc-shaped guide body (23) and the arc-shaped guide ring (24); In the gas flow direction, the distance between the outer wall of the arc-shaped guide body (23) and the inner wall of the arc-shaped guide ring (24) is equal everywhere.

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