Multi-process bidirectional pressure regulation semiconductor wafer polishing device and method

Abstract

The invention relates to a multi-process bidirectional pressure regulation semiconductor wafer polishing device and method. The device comprises a workbench, a polishing tool head, a feeding and discharging device, a main shaft module, a sliding table and a plurality of pressure control modules, and the pressure control modules are installed on the workbench; the polishing tool head is installed on the main shaft module, the workbench and the main shaft module are both installed on the sliding table, the sliding table is used for adjusting the height position of the main shaft module, the main shaft module applies pressure to a wafer in a rough adjustment mode through lead screw feeding, and each pressure control module is provided with a pressure sensor and a micro-nano driving platform. A to-be-polished semiconductor wafer is placed at the top ends of the pressure control modules, the feeding and discharging device is used for completing feeding and discharging after machining of the to-be-polished semiconductor wafer, the pressure control modules conduct online detection on polishing pressure on different stations / procedures, and the pressure during polishing is dynamically and accurately adjusted through the micro-nano driving platform. And the optimal machining parameters of each wafer are kept all the time, and polishing machining of the wafers is completed.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor processing technology, and in particular to a multi-process bidirectional pressure-regulated semiconductor wafer polishing device and method. Background Art

[0002] In the modern semiconductor manufacturing process, polishing technology is widely used in wafer flattening. Polishing is an important step to ensure the quality of subsequent processes and the performance of finished products by removing surface and subsurface damage of the wafer and achieving the required sub-nanometer surface roughness, nanometer subsurface damage depth and sub-micron surface accuracy. With the continuous advancement of semiconductor technology, the increase in wafer size, the increase in circuit complexity and the use of hard and brittle semiconductor materials represented by SiC and GaN, the requirements for wafer polishing technology are becoming higher and higher.

[0003] Traditional polishing methods usually involve multiple processes and stations to ensure the processing quality and efficiency of wafers. Reasonable coordination of different processes and stations to achieve the integration, automation and intelligence of multi-process / multi-station polishing is very important for improving processing efficiency and yield rate. However, the existing multi-process and multi-station polishing technology has challenges in terms of wafer surface quality, processing quality consistency, system stability, etc. Therefore, it is urgent to develop a multi-process, multi-station, high-quality, efficient and stable wafer polishing device and method. Summary of the invention

[0004] In response to the technical problems raised above, a semiconductor wafer polishing device and method with multi-process bidirectional pressure regulation is provided.

[0005] The technical means adopted by the present invention are as follows:

[0006] A multi-process bidirectional pressure-regulated semiconductor wafer polishing device comprises: a workbench, a polishing tool head, a loading and unloading device, a spindle module, a slide and several pressure control modules, wherein the pressure control module is mounted on the workbench; the polishing tool head is mounted on the spindle module, and the workbench and the spindle module are both mounted on the slide, and the slide is used to adjust the height position of the spindle module, and the spindle module applies pressure to the wafer for coarse adjustment through screw feeding, and each pressure control module is provided with a pressure sensor and a micro-nano driving platform, and the semiconductor wafer to be polished is placed on the top of the pressure control module, and the loading and unloading device is used to complete the loading and unloading of the semiconductor wafer to be polished after processing, and based on preset indicators, each pressure control module performs online detection of the polishing pressure at different stations / processes, and dynamically and accurately adjusts the pressure during polishing through the micro-nano driving platform, so that each wafer always maintains the optimal processing parameters, and completes the polishing process of the wafer.

[0007] Furthermore, the pressure control module includes a wafer placement table, a pressure sensor, a micro-nano drive platform, a conductive slip ring, a working output shaft, a coupling and a wafer motor. The conductive slip ring stator and the work table are connected by bolts, the wafer placement table, the pressure sensor, the micro-nano drive platform and the conductive slip ring mover are connected by bolts, the output end of the wafer motor is connected to the working output shaft through a coupling, and the output end of the working output shaft is connected to the conductive slip ring mover. The pressure sensor can obtain the interaction force between the polishing tool head and the wafer in real time. The micro-nano drive platform adjusts the height of the wafer placement table through micro-nano drive technology, and further adjusts the pressure between the polishing tool head.

[0008] Furthermore, the polishing tool head comprises a polishing disc and a polishing pad, and the polishing disc and the polishing pad are arranged according to the requirements of the processing technology.

[0009] Furthermore, the polishing tool head can be directly used for chemical mechanical polishing and electrochemical mechanical polishing, and light / laser-assisted chemical mechanical polishing and electrochemical mechanical polishing can be adjusted to groove and open holes on the polishing disc and polishing pad according to the type of light source.

[0010] Furthermore, the spindle module includes a spindle motor, a coupling, a bearing, a spindle fixed table, a spindle conductive slip ring, a light source device and a tool head flange. The spindle fixed table is fixed to the spindle conductive slip ring stator by bolts, and the other end is fixed on the slide. The spindle motor is connected to the tool head flange through a coupling, and the spindle conductive slip ring mover is connected to the tool head flange by bolts. The tool head flange is detachably connected to the polishing tool head. A polishing liquid storage structure is provided above the spindle fixed table, and a plurality of liquid supply pipe interfaces are provided. Polishing liquid is provided to the working area through the liquid supply pipe. One end of the liquid supply pipe is connected to the spindle fixed table, and the other end extends deep above the polishing disk. A flow control valve for controlling the flow of polishing liquid is provided on the liquid supply pipe.

[0011] Furthermore, a ring-arranged light source is provided at the bottom of the light source device, and the light source device is connected to the tool head flange through bolts. The light source is irradiated onto the workpiece through the polishing disc and the polishing pad, and the spindle conductive slip ring provides electrical energy for the light source.

[0012] Furthermore, the slide module includes a lead screw, a slide motor, a housing, and a slider. The slider is fixed to the spindle module by bolts. The slide motor realizes the up and down movement of the slider through the lead screw, and further realizes the application of pressure on the wafer through the polishing tool head. The slide module is connected to the external stand by bolts.

[0013] The present invention also discloses a multi-process bidirectional pressure-regulated semiconductor wafer polishing method, in which the control system polishes the wafer based on a plurality of motion modes, including micro-nano driving of the wafer by the pressure control module, rotational motion of the wafer by the pressure control module, rotational motion of the spindle, and up and down movement between the polishing tool head and the wafer realized by the slide.

[0014] Furthermore, during multiple processing steps, the pressure between the polishing pad and the wafer is coarsely adjusted by feeding the screw of the spindle module, and multiple pressure control modules are driven based on the control system to adjust the pressure between the wafer and the polishing tool head, so that each individual process reaches the optimal processing pressure of that process, and different processes are processed synchronously.

[0015] Furthermore, the method specifically includes the following steps:

[0016] A multi-step bidirectional pressure regulating semiconductor wafer polishing method, such as Figure 6 As shown, the following steps are included:

[0017] Step 1: Develop a wafer polishing plan, determine the processing steps for each station and the polishing pressure parameters required for each step;

[0018] Step 2: Input the optimal polishing pressure for the corresponding workstation;

[0019] Step 3: drive the micro-nano driving platform to move upward, and the loading and unloading industrial robot places the wafer on the wafer workbench of the corresponding station;

[0020] Step 4, drive the slide motor to move the polishing tool head to contact the wafer and apply pressure to the wafer. When any pressure sensor data is close to the set pressure, stop the slide motor and stop moving the polishing tool head.

[0021] Step 5: Drive the micro-nano driving platform to move the wafer placement table, accurately adjust the pressure between the wafer and the wafer placement table, and when the set pressure is reached, the light source needs to be turned on for chemical mechanical polishing and electrochemical mechanical polishing assisted by light / laser, and no light source is required for chemical mechanical polishing and electrochemical mechanical polishing. Turn on the liquid supply pipe switch to provide polishing liquid to the working area, start the wafer motor and the spindle motor, and start polishing the wafer;

[0022] Step 6: The pressure sensor detects the pressure of each station during polishing in real time. When the pressure does not meet the initial setting, it is fed back to the micro-nano driving platform to move the wafer placement table, quickly respond and adjust the pressure between the wafer placement table and the polishing tool head;

[0023] Step 7. After the polishing of a single wafer is completed, the corresponding wafer motor stops rotating, the corresponding micro-nano drive platform descends, the loading and unloading industrial robot picks up the workpiece, completes the polishing of the single wafer, and places the next workpiece to be processed. After the polishing of all wafers is completed, the micro-nano drive platform descends, and the loading and unloading industrial robots pick up the workpieces in turn.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] 1. In the present invention, by setting up a plurality of independent wafer workstations and independently installing fast-response pressure regulating devices, the pressure between the plurality of wafers and the polishing pad can be adjusted individually, and in the processing of multiple stations in the same process / multiple stations in multiple processes / multiple processes in the same station / multiple processes, the surface accuracy problems caused by the preparation and wear of the polishing pad can be compensated. In the processing of multiple processes in the same station, by accurately adjusting the polishing pressure required by different polishing processes, the same station can realize the processing of multiple processes such as rough polishing, semi-finishing polishing, and fine polishing. In the processing of multiple processes, the polishing pressure required by different processes can be accurately adjusted to realize the processing of the whole process such as rough polishing, semi-finishing polishing, and fine polishing of the wafer at the same station. It integrates multiple stations and multiple processes into one, improves the processing efficiency, saves the processing time, omits the transportation process between different processes, and reduces the processing cost and equipment cost.

[0026] 2. In the present invention, by providing a fast-response pressure detection device and a pressure regulating device, it is ensured that the optimal polishing pressure is always maintained during the polishing process, thereby improving the wafer surface processing quality and material removal rate.

[0027] 3. In the present invention, by setting a light source and an industrial loading and unloading robot, chemical mechanical polishing processing assisted by light / laser and automatic loading and unloading are realized simultaneously, and it has the characteristics of high degree of automation and high degree of integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0029] Figure 1 It is a structural schematic diagram of a semiconductor wafer polishing device with multi-process bidirectional pressure regulation according to the present invention;

[0030] Figure 2 is a partial cross-sectional view of the pressure control module of the present invention;

[0031] Figure 3It is a schematic diagram of the working area structure of the present invention;

[0032] Figure 4 This is a schematic diagram of the structure of the spindle module of the present invention;

[0033] Figure 5 A schematic diagram of a polishing tool head and a light source in an embodiment of the present invention;

[0034] Figure 6 This is a flow chart of the polishing process method of the present invention;

[0035] In the figure: 1. workbench; 2. pressure control module; 3. polishing tool head; 4. loading and unloading industrial robot; 5. spindle module; 6. slide; 201. wafer placement table; 202. pressure sensor; 203. micro-nano drive platform; 204. conductive slip ring mover; 205. conductive slip ring stator; 206. working output shaft; 207. coupling; 208. wafer motor; 301. polishing disk; 302. polishing pad; 501. spindle motor; 502. coupling; 503. bearing; 504. spindle fixing table; 505. spindle conductive slip ring stator; 506. light source device; 507. tool head flange; 508. spindle conductive slip ring mover; 509. liquid supply pipe; 601. housing; 602. slide motor; 603. lead screw; 604. slider. DETAILED DESCRIPTION

[0036] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0037] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0039] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, the numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be clear that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0040] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention: the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0041] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below their position devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0042] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0043] like Figures 1 to 5As shown, an embodiment of the present invention discloses a multi-process bidirectional pressure-regulated semiconductor wafer polishing device, comprising: a workbench 1, a polishing tool head 3, a loading and unloading device, a spindle module 5, a slide 6 and a plurality of pressure control modules 2, wherein the pressure control module is mounted on the workbench; the polishing tool head is mounted on the spindle module, the workbench and the spindle module are both mounted on a slider 604 of the slide, the slide is used to adjust the height position of the spindle module, the workbench and the slide are fixed by bolts, the spindle module applies pressure to the wafer coarse adjustment by screw feeding, each pressure control module is provided with a pressure sensor and a micro-nano driving platform, the semiconductor wafer to be polished is placed on the top of the pressure control module, the loading and unloading device is used to complete the loading and unloading of the semiconductor wafer to be polished after processing, based on preset indicators, each pressure control module performs online detection of the polishing pressure at different stations / processes, and dynamically and accurately adjusts the pressure during polishing through the micro-nano driving platform, so that each wafer always maintains the optimal processing parameters, and completes the polishing process of the wafer. The device and method of the present invention have the characteristics of high automation, high integration, high efficiency and high intelligence, and can simultaneously realize multi-step polishing processing of wafers.

[0044] In this embodiment, the loading and unloading device uses an loading and unloading industrial robot 4. The loading and unloading industrial robot can adopt a multi-posture conversion mechanical arm structure or other devices capable of completing wafer extraction and placement, and load and unload materials into a preset finished product storage mechanism.

[0045] The pressure control module includes a wafer placement table 201, a pressure sensor 202, a micro-nano drive platform 203, a conductive slip ring, a working output shaft 206, a coupling 207 and a wafer motor 208, wherein the conductive slip ring includes a conductive slip ring stator and a conductive slip ring mover, the conductive slip ring stator 205 and the workbench are connected by bolts, the wafer placement table, the pressure sensor, the micro-nano drive platform and the conductive slip ring mover 204 are connected by bolts, the output end of the wafer motor is connected to the working output shaft through a coupling, and the output end of the working output shaft is connected to the conductive slip ring mover. The wafer placement table has a vacuum adsorption effect, which can limit the 6 degrees of freedom of the wafer, and the pressure sensor provided on the pressure control module can respectively perform online detection of the polishing pressure on different stations / processes, and the pressure during polishing is accurately adjusted in real time through the micro-nano drive technology of the micro-nano drive platform, so that each wafer always maintains the optimal processing parameters and completes the polishing process of the wafer.

[0046] Specifically, the pressure sensor can obtain the interaction force between the polishing tool head and the wafer in real time. The micro-nano driving platform accurately adjusts the height of the wafer placement table through micro-nano driving technology, further adjusts the pressure between the polishing tool head, and controls each wafer placement table separately in combination with the control system.

[0047] The polishing tool head includes a polishing disc 301 and a polishing pad 302, and the polishing disc and the polishing pad are set according to the requirements of the processing technology. Specifically, the polishing tool head can be directly used for chemical mechanical polishing and electrochemical mechanical polishing, and the chemical mechanical polishing and electrochemical mechanical polishing assisted by light / laser are adjusted by slotting and opening holes for the polishing disc and the polishing pad according to the type of light source.

[0048] The spindle module includes a spindle motor 501, a coupling 502, a bearing 503, a spindle fixed platform 504, a spindle conductive slip ring, a light source device 506, a tool head flange 507 and a liquid supply pipe 508. The spindle fixed platform is fixed to the spindle conductive slip ring stator 505 by bolts, and the other end is fixed on the slide. The spindle motor is connected to the tool head flange through a coupling. The spindle conductive slip ring mover 509 is connected to the tool head flange by bolts. The tool head flange is detachably connected to the polishing tool head by bolts. A polishing liquid storage structure is provided above the spindle fixed platform, and polishing liquid is provided to the working area through a liquid supply pipe. One end of the liquid supply pipe is connected to the spindle fixed platform, and the other end extends to the top of the polishing disk. A flow control valve is provided on the liquid supply pipe to control the flow of polishing liquid.

[0049] A ring-shaped light source is arranged at the bottom of the light source device. The light source device is connected to the tool head flange by bolts. The light source is irradiated onto the workpiece through the polishing disk and the polishing pad. The spindle conductive slip ring (including the spindle conductive slip ring stator 505 and the spindle conductive slip ring mover 508) ensures the rotation of the wafer in the pressure module while providing electrical energy for the light source. The spindle conductive slip ring mover is connected to the tool head flange by bolts.

[0050] The slide module includes a lead screw 603, a slide motor 602, a housing 601, and a slider 604. The slider is fixed to the spindle module by bolts. The slide motor realizes the up and down movement of the slider through the lead screw, and further realizes the application of pressure to the wafer through the polishing tool head. The slide module is connected to the external stand by bolts.

[0051] The present invention also discloses a multi-process bidirectional pressure-regulated semiconductor wafer polishing method, in which the control system polishes the wafer based on multiple motion modes, including micro-nano driving of the wafer by the pressure control module, rotational motion of the wafer by the pressure control module, rotational motion of the spindle, up and down movement between the polishing tool head and the wafer realized by the slide, and automatic loading and unloading movement-rotation of the loading and unloading industrial robot.

[0052] During multiple processing steps, the pressure between the polishing pad and the wafer is coarsely adjusted through the screw feed of the spindle module. Based on the control system, multiple pressure control modules are driven to adjust the pressure between the wafer and the polishing tool head, so that each individual process can achieve the optimal processing pressure of that process and process different processes can be processed simultaneously.

[0053] like Figure 6 As shown, a multi-step bidirectional pressure regulation semiconductor wafer polishing method specifically includes the following steps:

[0054] Step 1: Develop a wafer polishing plan, determine the processing steps for each station and the polishing pressure parameters required for each step;

[0055] Step 2: Input the optimal polishing pressure for the corresponding workstation;

[0056] Step 3: drive the micro-nano driving platform to move upward, and the loading and unloading industrial robot places the wafer on the wafer workbench of the corresponding station;

[0057] Step 4, drive the slide motor to move the polishing tool head to contact the wafer and apply pressure to the wafer. When any pressure sensor data is close to the set pressure, stop the slide motor and stop moving the polishing tool head.

[0058] Step 5: Drive the micro-nano driving platform to move the wafer placement table, accurately adjust the pressure between the wafer and the wafer placement table, and when the set pressure is reached, the light source needs to be turned on for chemical mechanical polishing and electrochemical mechanical polishing assisted by light / laser, and no light source is required for chemical mechanical polishing and electrochemical mechanical polishing. Turn on the liquid supply pipe switch to provide polishing liquid to the working area, start the wafer motor and the spindle motor, and start polishing the wafer;

[0059] Step 6: The pressure sensor detects the pressure of each station during polishing in real time. When the pressure does not meet the initial setting, it is fed back to the micro-nano driving platform to move the wafer placement table, quickly respond and adjust the pressure between the wafer placement table and the polishing tool head;

[0060] Step 7. After the polishing of a single wafer is completed, the corresponding wafer motor stops rotating, the corresponding micro-nano drive platform descends, the loading and unloading industrial robot picks up the workpiece, completes the polishing of the single wafer, and places the next workpiece to be processed. After the polishing of all wafers is completed, the micro-nano drive platform descends, and the loading and unloading industrial robots pick up the workpieces in turn.

[0061] The material removal rate (MRR) in chemical mechanical polishing can be calculated according to the Princeton formula:

[0062] MRR = kpv

[0063] Where k is the Princeton coefficient, p is the polishing pressure, and v is the relative motion speed between the wafer and the polishing pad.

[0064] The use method can adjust the polishing pressure to always maintain the optimal processing parameters, which is beneficial to improving the material removal rate.

[0065] The method of use described above has different goals in multi-step polishing processing. The polishing pressure suitable for the rough polishing stage can improve the material removal rate but the surface quality is poor. The polishing pressure suitable for the fine polishing stage can obtain good surface quality, but the material removal rate is low. By adjusting the polishing pressure, multi-step polishing can be achieved.

[0066] Based on the above equipment and method, the present invention can adopt the following specific implementation methods to complete a variety of processing requirements.

[0067] Embodiment 1

[0068] Semiconductor wafer polishing in multiple stations in the same process / multiple processes in the same station / multiple processes, combined Figure 1 and Figure 6 Wafer semiconductor polishing is an ultra-precision processing technology at the atomic level. There are surface accuracy problems in the preparation and wear of polishing pads and polishing discs. The change pattern of polishing pressure can be detected by pressure sensors. The wafer placement table can be moved by a micro-nano drive platform to adjust the polishing pressure in real time to ensure that the polishing pressure is always the optimal processing pressure, thereby achieving efficient and ultra-low damage processing of the wafer.

[0069] Embodiment 2

[0070] Semiconductor wafer polishing at multiple stations in the same process, combined with Figure 1 and Figure 6 , rough polishing / semi-finishing polishing / finishing polishing processes are carried out simultaneously, and 6 workstations are set to work simultaneously. Each workstation can ensure that the polishing pressure is always the optimal processing pressure, which improves the processing efficiency and processing accuracy of wafer polishing.

[0071] Embodiment 3

[0072] Semiconductor wafer polishing in multiple processes at the same station, combined Figure 1 and Figure 6 Each workstation performs multiple processes including rough polishing, semi-finishing polishing and finishing polishing. Six workstations are set up to work simultaneously. By accurately adjusting the polishing pressure required by different polishing processes, the entire process can be processed at the same workstation, omitting the processes of wafer handling and repeated cleaning after each process, thereby improving the processing efficiency of wafer polishing and reducing processing costs and equipment costs.

[0073] Embodiment 4

[0074] Semiconductor wafer polishing with different processes and multiple stations, combined Figure 1 and Figure 6 , 6 workstations are set up to work simultaneously, and each workstation can freely allocate and combine rough polishing, semi-finishing polishing and fine polishing processes, which improves the processing efficiency of wafer polishing and reduces processing costs and equipment costs.

[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-process bidirectional pressure regulating semiconductor wafer polishing device, characterized in that: include: A workbench, a polishing tool head, a loading and unloading device, a spindle module, a slide and several pressure control modules, wherein the pressure control module is installed on the workbench; the polishing tool head is installed on the spindle module, and the workbench and the spindle module are both installed on the slide, and the slide is used to adjust the height position of the spindle module, and the spindle module applies pressure to the wafer for coarse adjustment through screw feeding, and each pressure control module is provided with a pressure sensor and a micro-nano driving platform, and the semiconductor wafer to be polished is placed on the top of the pressure control module, and the loading and unloading device is used to complete the loading and unloading of the semiconductor wafer to be polished after processing, and based on preset indicators, each pressure control module performs online detection of the polishing pressure at different stations / processes, and dynamically and accurately adjusts the pressure during polishing through the micro-nano driving platform, so that each wafer always maintains the optimal processing parameters to complete the polishing process of the wafer.

2. The multi-process bidirectional pressure regulating semiconductor wafer polishing device according to claim 1 is characterized in that: The pressure control module includes a wafer placement table, a pressure sensor, a micro-nano driving platform, a conductive slip ring, a working output shaft, a coupling and a wafer motor. The conductive slip ring stator and the working table are connected by bolts, the wafer placement table, the pressure sensor, the micro-nano driving platform and the conductive slip ring mover are connected by bolts, the output end of the wafer motor is connected to the working output shaft through a coupling, and the output end of the working output shaft is connected to the conductive slip ring mover. The pressure sensor can obtain the interaction force between the polishing tool head and the wafer in real time. The micro-nano driving platform adjusts the height of the wafer placement table through micro-nano driving technology, and further adjusts the pressure between the polishing tool head.

3. The multi-process bidirectional pressure regulating semiconductor wafer polishing device according to claim 1 is characterized in that: The polishing tool head comprises a polishing disc and a polishing pad, and the polishing disc and the polishing pad are arranged according to the requirements of the processing technology.

4. The multi-process bidirectional pressure regulating semiconductor wafer polishing device according to claim 3 is characterized in that: The polishing tool head can be directly used for chemical mechanical polishing and electrochemical mechanical polishing. Light / laser-assisted chemical mechanical polishing and electrochemical mechanical polishing are adjusted for grooving and opening holes on the polishing disc and polishing pad according to the type of light source.

5. The multi-process bidirectional pressure regulating semiconductor wafer polishing device according to claim 1 is characterized in that: The spindle module includes a spindle motor, a coupling, a bearing, a spindle fixing table, a spindle conductive slip ring, a light source device, a tool head flange and a liquid supply pipe. The spindle fixing table is fixed to the spindle conductive slip ring stator by bolts, and the other end is fixed on the slide. The spindle motor is connected to the tool head flange through a coupling, and the spindle conductive slip ring mover is connected to the tool head flange by bolts. The tool head flange is detachably connected to the polishing tool head. A polishing liquid storage structure is provided above the spindle fixing table, and a plurality of liquid supply pipe interfaces are provided. Polishing liquid is provided to the working area through the liquid supply pipe. One end of the liquid supply pipe is connected to the spindle fixing table, and the other end extends above the polishing disk. A flow control valve for controlling the flow of polishing liquid is provided on the liquid supply pipe.

6. The multi-step bidirectional pressure regulating semiconductor wafer polishing device according to claim 5 is characterized in that: A circularly arranged light source is provided at the bottom of the light source device. The light source device is connected to the tool head flange through bolts. The light source is irradiated onto the workpiece through the polishing disc and polishing pad. The spindle conductive slip ring is used to provide electrical energy for the light source.

7. The multi-step bidirectional pressure regulating semiconductor wafer polishing device according to claim 1 is characterized in that: The slide module includes a lead screw, a slide motor, a housing, and a slider. The slider is fixed to the spindle module by bolts. The slide motor realizes the up and down movement of the slider through the lead screw, and further realizes the application of pressure to the wafer through the polishing tool head. The slide module is connected to the external stand by bolts.

8. A polishing method based on the multi-step bidirectional pressure regulating semiconductor wafer polishing device according to any one of claims 1 to 7, characterized in that: The control system polishes the wafer based on a variety of motion modes, including micro-nano drive of the wafer by the pressure control module, rotational movement of the wafer by the pressure control module, rotational movement of the spindle, and up and down movement between the polishing tool head and the wafer achieved by the slide.

9. The method according to claim 8, characterized in that During multiple processing steps, the pressure between the polishing pad and the wafer is coarsely adjusted through the screw feed of the spindle module. Based on the control system, multiple pressure control modules are driven to adjust the pressure between the wafer and the polishing tool head, so that each individual process can achieve the optimal processing pressure of that process and process different processes can be processed simultaneously.

10. The method according to claim 8, characterized in that The specific steps include: A multi-step bidirectional pressure-regulated semiconductor wafer polishing method comprises the following steps: Step 1: Develop a wafer polishing plan, determine the processing steps for each station and the polishing pressure parameters required for each step; Step 2: Input the optimal polishing pressure for the corresponding workstation; Step 3: drive the micro-nano driving platform to move upward, and the loading and unloading industrial robot places the wafer on the wafer workbench of the corresponding station; Step 4, drive the slide motor to move the polishing tool head to contact the wafer and apply pressure to the wafer. When any pressure sensor data is close to the set pressure, stop the slide motor and stop moving the polishing tool head. Step 5: Drive the micro-nano driving platform to move the wafer placement table, accurately adjust the pressure between the wafer and the wafer placement table, and when the set pressure is reached, the light source needs to be turned on for chemical mechanical polishing and electrochemical mechanical polishing assisted by light / laser, and no light source is required for chemical mechanical polishing and electrochemical mechanical polishing. Turn on the liquid supply pipe switch to provide polishing liquid to the working area, start the wafer motor and the spindle motor, and start polishing the wafer; Step 6: The pressure sensor detects the pressure of each station during polishing in real time. When the pressure does not meet the initial setting, it is fed back to the micro-nano driving platform to move the wafer placement table, quickly respond and adjust the pressure between the wafer placement table and the polishing tool head; Step 7. After the polishing of a single wafer is completed, the corresponding wafer motor stops rotating, the corresponding micro-nano drive platform descends, the loading and unloading industrial robot picks up the workpiece, completes the polishing of the single wafer, and places the next workpiece to be processed. After the polishing of all wafers is completed, the micro-nano drive platform descends, and the loading and unloading industrial robots pick up the workpieces in turn.

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