TSV etching equipment and cleaning method

Abstract

The embodiments of this specification provide a TSV etching device and a cleaning method, wherein the TSV etching device includes a cavity, an electrostatic chuck and a lower electrode module, wherein the lower electrode module is installed in the cavity, the electrostatic chuck is installed on the top of the lower electrode module, the lower electrode module includes a lower electrode and a support portion, and the support portion is connected to the inner bottom wall of the cavity; an isolation mesh plate is arranged between the electrostatic chuck and the cavity; a purge mechanism includes an air supply pipeline and a purge portion, the purge portion is arranged around the support portion, the air supply pipeline is used to supply air to the purge portion, and the purge portion purges the polymer adhered to the support portion; an exhaust pipe is connected to the purge pump, and the exhaust pipe extends to the interior of the cavity. By arranging a purge mechanism to purge the support portion, the air supply pipeline is used to supply air to the purge portion, the purge portion purges the polymer adhered to the support portion, and the purge pump extracts the polymer blown off the support portion, thereby realizing the cleaning operation of the lower electrode module under the electrostatic chuck.

Description

Technical Field

[0001] The present invention relates to the field of wafer etching technology, and in particular to a TSV etching device and a cleaning method. Background Art

[0002] For ICP (inductively coupled cavity) type TSV process, the gas used in TSV is generally fluorocarbon gas, which will produce some polymers during the etching process. When the polymer reaches a certain thickness, it will cause particle contamination to the cavity and damage the etching surface. Generally, Plasma plus SF6 and O2 gas can be used to remove polymers. The TSV electrostatic chuck generally uses low temperature process, which has adsorption to polymers, resulting in SF6 and O2 gases being unable to fully remove the side wall below the electrostatic chuck (such as part of the lower electrode module). Summary of the invention

[0003] In view of this, the embodiments of the present specification provide a TSV etching device and a cleaning method, in which a purge mechanism is provided to purge the support part, and an air supply pipeline is used to supply air to the purge part. The purge part will purge the polymer adhered to the support part, and the pneumatic pump will extract the polymer blown off the support part, thereby realizing the cleaning operation of the lower electrode module under the electrostatic suction cup.

[0004] The embodiments of this specification provide the following technical solutions: a TSV etching device, the TSV etching device comprising a chamber, an electrostatic chuck and a lower electrode module, the lower electrode module is installed in the chamber, the electrostatic chuck is installed on the top of the lower electrode module, the electrostatic chuck is used to adsorb the wafer, the lower electrode module comprises a lower electrode and a support part, the support part is connected to the bottom wall of the chamber, and the lower electrode is arranged on the top of the support part;

[0005] The TSV etching equipment further includes:

[0006] An isolation mesh plate, the isolation mesh plate is arranged between the electrostatic chuck and the cavity, and the outer side of the isolation mesh plate is connected to the inner wall of the cavity;

[0007] A purge mechanism, the purge mechanism comprising an air supply pipeline and a purge portion, the purge portion being arranged around the support portion, the air supply pipeline being used to supply air to the purge portion, and the purge portion purges the polymer adhered to the support portion;

[0008] A pneumatic pump is connected to the pneumatic pump and is provided with an air extraction pipe, and the air extraction pipe extends into the interior of the cavity.

[0009] Preferably, the purge part includes a plurality of purge rings, which are arranged around the support part, and a hollow area is formed inside the purge rings, which are connected to the air supply pipeline. A plurality of purge holes are opened on one side of the purge ring close to the support part, and the purge holes are connected to the hollow area.

[0010] Preferably, the purge hole is a downwardly inclined hole.

[0011] Preferably, the plurality of purge holes are evenly distributed in a ring shape on the purge ring.

[0012] Preferably, the gas supply pipeline includes a first pipeline and a second pipeline, the first pipeline passes through the cavity and is connected to an external nitrogen source, the first end of the second pipeline is connected to the first pipeline, the second end of the second pipeline is connected to the purge part, and the second pipeline is a deformable pipeline.

[0013] Preferably, the purge mechanism further includes a lifting portion, and the lifting portion is used to drive the purge portion to move along the axial direction of the support portion.

[0014] Preferably, the lifting part comprises a cylinder, a fixed end of the cylinder is connected to the cavity, and a telescopic end of the cylinder is connected to the purge part.

[0015] Preferably, the TSV etching equipment further comprises a ceramic ring, wherein the ceramic ring is arranged around the electrostatic chuck, the top of the ceramic ring forms a bearing portion, and the isolation mesh plate is in contact with the bearing portion.

[0016] The TSV etching equipment further includes a quartz ring, which is at least partially disposed around the electrostatic chuck and / or the lower electrode.

[0017] A cleaning method is applied to the TSV etching device as described in any one of the above items, wherein the cleaning method cleans the support portion when the electrostatic chuck is not working, and comprises the following steps:

[0018] When cleaning is performed, an external nitrogen source supplies gas to the purge part through a gas supply pipeline, and the purge part purges the polymer adhered to the support part;

[0019] Start the pneumatic pump, which will extract the polymer that has been blown down through the suction pipe.

[0020] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0021] The support part is purged by setting up a purge mechanism, and the air supply pipeline is used to supply air to the purge part. The purge part will purge the polymer adhering to the support part, and the pneumatic pump will extract the polymer blown off the support part, thereby realizing the cleaning operation of the lower electrode module under the electrostatic suction cup. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It is a structural schematic diagram of the TSV etching equipment provided by the present application;

[0024] Figure 2 It is a schematic diagram of the structure of the purge ring of the TSV etching equipment provided by the present application;

[0025] Figure 3 It is a cross-sectional view of the purge ring of the TSV etching equipment provided in the present application.

[0026] In the figure, 1, cavity; 2, electrostatic suction cup; 3, lower electrode; 4, support part; 5, isolation mesh plate; 6, purge part; 61, purge ring; 62, purge hole; 7, gas supply pipeline; 71, first pipeline; 72, second pipeline; 8, exhaust pipe; 9, ceramic ring; 10, quartz ring; 11, lifting part; 12, polymer. DETAILED DESCRIPTION

[0027] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0028] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0029] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0030] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0031] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects described may be practiced without these specific details.

[0032] Plasma etching: In a typical plasma etching process, different process gas combinations are excited by radio frequency in a radio frequency environment to form plasma. The formed plasma physically bombards and chemically reacts with the wafer surface under the action of the electric field of the upper and lower electrodes of the etching chamber, completing the processing of the wafer surface design pattern and key processes. Typical etching chambers include capacitively coupled chambers (CCP) and inductively coupled chambers (ICP).

[0033] For ICP type TSV process, the gas used for TSV is generally fluorinated gas. Some polymers will be generated during the etching process, which will affect the collision, adsorption and recombination of active ions and electrons. When the polymer reaches a certain thickness, it will cause particle contamination to the cavity and damage the etching surface. Generally, Plasma plus SF6 and O2 gas can be used to remove polymers. The general process temperature of TSV electrostatic chuck is low temperature, and low temperature has adsorption to polymers, resulting in SF6 and O2 gases unable to fully remove the side wall below the electrostatic chuck (such as part of the lower electrode module).

[0034] After extensive and in-depth experiments, the inventors designed a TSV etching device and a cleaning method.

[0035] The technical solutions provided by various embodiments of the present application are described below in conjunction with the accompanying drawings.

[0036] like Figure 1-Figure 3 As shown, a TSV etching device comprises a chamber 1, an electrostatic chuck 2 and a lower electrode 3 module, wherein the lower electrode 3 module is installed in the chamber 1, the electrostatic chuck 2 is installed on the top of the lower electrode 3 module, the electrostatic chuck 2 is used to adsorb wafers, the lower electrode 3 module comprises a lower electrode 3 and a support portion 4, the support portion 4 is connected to the inner bottom wall of the chamber 1, the support portion 4 is a columnar structure, the support portion 4 is fixedly installed in the chamber 1, the lower electrode 3 is arranged on the top of the support portion 4, and the electrostatic chuck 2 is installed on the top of the lower electrode 3;

[0037] The TSV etching equipment further includes:

[0038] An isolation mesh plate 5, wherein the isolation mesh plate 5 is disposed between the electrostatic chuck 2 and the cavity 1, and the outer side of the isolation mesh plate 5 is connected to the inner wall of the cavity 1;

[0039] A purge mechanism, the purge mechanism comprising an air supply pipeline 7 and a purge portion 6, the purge portion 6 being arranged around the support portion 4, the air supply pipeline 7 being used to supply air to the purge portion 6, and the purge portion 6 purges the polymer 12 adhered to the support portion 4;

[0040] A pneumatic pump is connected to the pneumatic pump and an air extraction pipe 8 is extended into the cavity 1 .

[0041] The support part 4 is purged by setting a purging mechanism, and the air supply pipeline 7 is used to supply air to the purging part 6. The purging part 6 will purge the polymer 12 adhered to the support part 4. The purging part 6 is arranged around the support part 4, which can ensure that the support part 4 is purged evenly and the purging effect of the support part 4 is ensured. The purged polymer 12 falls into the cavity 1, and the pneumatic pump extracts the purged polymer 12 on the support part 4 through the exhaust pipe 8, thereby realizing the cleaning operation of the lower electrode 3 module under the electrostatic suction cup 2.

[0042] It should be noted that the polymer 12 above the support portion 4 can be directly removed by beating Plasma. Due to the existence of the isolation mesh plate 5, it is difficult to clean the polymer 12 adhered to the outer wall of the support portion 4 only by beating Plasma. Therefore, the support portion 4 is purged by a purging mechanism.

[0043] It should also be noted that the speed of the wind pump is above 30,000 revolutions, which can ensure that the polymer 12 in the cavity 1 can be extracted.

[0044] like Figure 1-Figure 3As shown, in some embodiments, the purge portion 6 includes a plurality of purge rings 61, and the plurality of purge rings 61 are arranged around the support portion 4. A hollow area is formed inside the purge ring 61, and the hollow area is connected to the gas supply pipeline 7. A plurality of purge holes 62 are opened on one side of the purge ring 61 close to the support portion 4, and the purge holes 62 are connected to the hollow area. By using the purge ring 61 to purge the support portion 4, the gas supply pipeline 7 supplies the purge gas into the hollow area inside the purge ring 61, and then blows the purge gas toward the support portion 4 through the plurality of purge holes 62, thereby ensuring the purge effect on the polymer 12 adhered to the support portion 4.

[0045] It should be noted that, in the present embodiment, the number of the purge ring 61 is one, and in other embodiments, the number of the purge ring 61 may be two or more, which can be set according to actual conditions.

[0046] like Figure 2-Figure 3 As shown, in some embodiments, the purge hole 62 is a downwardly inclined hole. By setting the purge hole 62 as a downwardly inclined hole, the purge gas blown toward the support portion 4 through the purge hole 62 flows downward, thereby ensuring the purge effect on the support portion 4.

[0047] like Figure 2-Figure 3 As shown, in some embodiments, the plurality of purge holes 62 are evenly distributed in a ring shape on the purge ring 61 , and the plurality of purge holes 62 are evenly distributed around the support portion 4 , thereby achieving comprehensive and even purge of the support portion 4 and ensuring a cleaning effect on the support portion 4 .

[0048] like Figure 1 As shown, in some embodiments, the gas supply pipeline 7 includes a first pipe 71 and a second pipe 72, the first pipe 71 passes through the cavity 1 and is connected to an external nitrogen source, the first end of the second pipe 72 is connected to the first pipe 71, and the second end of the second pipe 72 is connected to the purge part 6, the second pipe 72 is a deformable pipe, the first pipe 71 passes through the cavity 1 and is connected to an external nitrogen source, and is purged with nitrogen, the second pipe 72 is connected to the purge part 6, and the second pipe 72 can be deformed so that the purge part 6 can move within a certain range relative to the support part 4.

[0049] like Figure 1 As shown, in some embodiments, the purge mechanism also includes a lifting portion 11, and the lifting portion 11 is used to drive the purge portion 6 to move along the axial direction of the support portion 4. By setting the lifting portion 11, the lifting portion 11 can drive the purge portion 6 to move up and down, thereby ensuring that the support portion 4 is fully purged. When the lifting portion 11 drives the purge portion 6 to move up and down, the second pipe 72 can be deformed, so it will not affect the movement of the purge portion 6.

[0050] like Figure 1 As shown, in some embodiments, the lifting part 11 includes a cylinder, the fixed end of the cylinder is connected to the cavity 1, and the telescopic end of the cylinder is connected to the purge part 6. The cylinder is used to drive the purge part 6 to move up and down. When the cylinder is extended, the purge part 6 moves upward to purge the upper area of ​​the support part 4. When the cylinder is contracted, the purge part 6 moves downward to purge the lower area of ​​the support part 4, thereby achieving comprehensive purge of the support part 4 and ensuring the cleaning effect.

[0051] It should be noted that, in other embodiments, the lifting part 11 may also adopt other structures such as electric cylinders and ball screws, which can be selected according to actual conditions.

[0052] like Figure 1 As shown, in some embodiments, the TSV etching equipment also includes a ceramic ring 9 and a quartz ring 10. The ceramic ring 9 is arranged around the electrostatic suction cup 2. The top of the ceramic ring 9 forms a bearing portion, and the isolation mesh plate 5 is in contact with the bearing portion; the quartz ring 10 is at least partially arranged around the electrostatic suction cup 2 and / or the lower electrode 3. By arranging the ceramic ring 9 and the quartz ring 10, support and protection are provided, and the device also has good insulation performance and corrosion resistance, which can meet the requirements for high precision and surface finish in the TSV manufacturing process.

[0053] See also Figure 1-Figure 3 Based on the same inventive concept, an embodiment of this specification provides a cleaning method, which is applied to the TSV etching equipment as described in any one of the above items, and the cleaning method cleans the support part 4 when the electrostatic chuck 2 is not working, and includes the following steps:

[0054] When cleaning, an external nitrogen source supplies gas to the purge portion 6 through the gas supply pipeline 7, and the purge portion 6 purges the polymer 12 adhered to the support portion 4;

[0055] The pneumatic pump is started, and the pneumatic pump draws away the polymer 12 that is blown down through the suction pipe 8 .

[0056] In practice, the purge unit 6 does not work during the TSV process, and the polymer 12 tends to cool. When plasma is blown during the TSV process, the temperature of the cavity 1 rises, and the polymer 12 generally does not adhere to the side wall. After the process is completed, the purge unit 6 is used for purge.

[0057] It should be noted that, when purging is performed, the lifting portion 11 can be used to drive the purge ring 61 to move up and down, thereby achieving a comprehensive purge of the support portion 4 and ensuring a cleaning effect on the support portion 4 .

[0058] The same or similar parts between the various embodiments in this specification can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the method embodiment described later, since it corresponds to the system, the description is relatively simple, and the relevant parts can be referred to the partial description of the system embodiment.

[0059] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A TSV etching device, comprising a chamber, an electrostatic chuck and a lower electrode module, wherein the lower electrode module is installed in the chamber, the electrostatic chuck is installed on the top of the lower electrode module, and the electrostatic chuck is used to adsorb a wafer, characterized in that: The lower electrode module comprises a lower electrode and a support portion, wherein the support portion is connected to the inner bottom wall of the cavity, and the lower electrode is arranged on the top of the support portion; The TSV etching equipment further includes: An isolation mesh plate, the isolation mesh plate is arranged between the electrostatic chuck and the cavity, and the outer side of the isolation mesh plate is connected to the inner wall of the cavity; A purge mechanism, the purge mechanism comprising an air supply pipeline and a purge part, the purge part being arranged around the support part, the air supply pipeline being used to supply air to the purge part, the purge part being used to purge the polymer adhered to the support part, the purge mechanism further comprising a lifting part, the lifting part being used to drive the purge part to move along the axial direction of the support part, so as to achieve comprehensive purge of the support part; A pneumatic pump is connected to the pneumatic pump and is provided with an air extraction pipe, and the air extraction pipe extends into the interior of the cavity.

2. The TSV etching equipment according to claim 1, characterized in that: The purge part includes a plurality of purge rings, which are arranged around the support part. A hollow area is formed inside the purge ring, and the hollow area is connected to the air supply pipeline. A plurality of purge holes are opened on one side of the purge ring close to the support part, and the purge holes are connected to the hollow area.

3. The TSV etching equipment according to claim 2, characterized in that: The purge hole is a hole inclined downward.

4. The TSV etching equipment according to claim 2, characterized in that: The plurality of purge holes are evenly distributed in an annular shape on the purge ring.

5. The TSV etching equipment according to any one of claims 1 to 4, characterized in that: The gas supply pipeline includes a first pipeline and a second pipeline, the first pipeline passes through the cavity and is connected to an external nitrogen source, the first end of the second pipeline is connected to the first pipeline, the second end of the second pipeline is connected to the purge part, and the second pipeline is a deformable pipeline.

6. The TSV etching equipment according to claim 1, characterized in that: The lifting part comprises a cylinder, a fixed end of the cylinder is connected to the cavity, and a telescopic end of the cylinder is connected to the purge part.

7. The TSV etching equipment according to claim 1, characterized in that: The TSV etching equipment further comprises a ceramic ring, which is arranged around the electrostatic chuck, and a bearing portion is formed on the top of the ceramic ring, and the isolation mesh plate is in contact with the bearing portion.

8. The TSV etching equipment according to claim 1, characterized in that: The TSV etching equipment further includes a quartz ring, which is at least partially disposed around the electrostatic chuck and / or the lower electrode.

9. A cleaning method, characterized in that: Applied to the TSV etching device according to any one of claims 1 to 8, the cleaning method cleans the support portion when the electrostatic chuck is not working, and comprises the following steps: When cleaning is performed, an external nitrogen source supplies gas to the purge part through a gas supply pipeline, and the purge part purges the polymer adhered to the support part; Start the pneumatic pump, which will extract the polymer that has been blown down through the suction pipe.

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