Wafer loading device

Abstract

The invention discloses a wafer loading device. The wafer loading device comprises a base; the bracket is positioned above the base; a detection assembly is arranged above the bracket, the detection assembly comprises a rod piece, the rod piece can swing up and down around a fixed point, and a balancing weight is arranged at the end of the rod piece; a pressure detection port is formed above the bracket, and the arrangement position of the balancing weight corresponds to that of the pressure detection port; the rod piece can drive the balancing weight to open or block the pressure detection opening along with whether the wafer is loaded on the rod piece or not and is in different states, so that whether the wafer is loaded or not is judged according to pressure changes.

Description

[0001] This application is a divisional application of the invention patent application filed on August 21, 2023, with application number 2023110488415. Technical Field

[0002] This invention belongs to the field of chemical mechanical polishing technology, and more specifically, relates to a wafer loading device. Background Technology

[0003] The integrated circuit industry is the core of the information technology industry, playing a crucial role in promoting the digital and intelligent transformation and upgrading of the manufacturing industry. Chips are the carriers of integrated circuits, and chip manufacturing involves processes such as integrated circuit design, wafer fabrication, wafer processing, electrical measurement, dicing, packaging, and testing. Among these, chemical mechanical polishing (CMP) is one of the five core processes in wafer fabrication.

[0004] Chemical mechanical polishing (CMP) is an ultra-precision surface finishing technique that achieves global planarization. In CMP, the wafer is typically held in place by the bottom surface of a support head, with the side of the wafer containing the deposited layer resting against the upper surface of a polishing pad. The support head rotates in the same direction as the polishing pad under the actuation of a drive assembly, applying a downward load to the wafer. Polishing fluid is supplied to the upper surface of the polishing pad and distributed between the wafer and the pad, allowing the wafer to undergo chemical and mechanical polishing through a combination of chemical and mechanical processes.

[0005] Chemical mechanical polishing systems are also equipped with wafer loading cups to enable wafer interaction. For example, a robotic arm places a wafer on a wafer loading / unloading device, and the loading head then picks up the wafer from the device and transfers it to the polishing pad. To ensure the continuity of wafer interaction, it is necessary to determine whether a wafer is loaded, i.e., whether a wafer is placed on the loading / unloading device.

[0006] In existing technologies, water pressure detection methods typically involve setting up a fluid channel inside the bracket, installing a pressure sensor at the inlet of the fluid channel, and setting the outlet of the fluid channel as a narrow orifice to determine whether the wafer is in place by measuring the change in the water pressure value of the fluid channel.

[0007] To control the contact area between the wafer and the carrier and prevent defects at the wafer edge, the wafer's bearing area needs to be narrowed to less than 1mm, which would prevent the fluid channels in the carrier from being processed.

[0008] Furthermore, existing wafer loading devices are unable to determine whether the trim wafer is in place because the wafer edge has a notch that cannot block the outlet of the fluid channel on the carrier, thus preventing any change in pressure.

[0009] Furthermore, when using existing testing methods, fluids under pressure come into direct contact with the wafer surface, which increases the chance of wafer contamination and affects the yield of wafer processing and manufacturing. Summary of the Invention

[0010] This invention provides a wafer loading apparatus designed to at least address one of the technical problems existing in the prior art.

[0011] A first aspect of the present invention provides a wafer loading apparatus, comprising:

[0012] Base;

[0013] The bracket is located above the base;

[0014] A detection component is arranged above the bracket. The detection component includes a rod that can swing up and down around a fixed point, and a counterweight is provided at its end.

[0015] A pressure detection port is provided above the bracket, and the counterweight is positioned corresponding to the pressure detection port. The rod is in different states depending on whether a wafer is loaded on it, and it can drive the counterweight to open or block the pressure detection port so as to determine whether a wafer is loaded by pressure changes.

[0016] In some embodiments, the position where the rod contacts the wafer to be loaded is provided with an inclined surface to control the contact area between the rod and the wafer.

[0017] In some embodiments, the number of detection components is multiple, and they are evenly distributed above the tray with reference to the center of the wafer loading area.

[0018] In some embodiments, one end of the rod is provided with an inclined surface, and the other end is provided with a counterweight.

[0019] In some embodiments, the bottom surface of the counterweight is a plane to block the pressure detection port when the wafer is not pressed against the rod.

[0020] In some embodiments, the detection component is further configured with a spring disposed between the swing point of the rod and the configuration block; the wafer to be loaded is pressed against the outside of the spring's location.

[0021] In some embodiments, the swing point of the rod is located inside or outside the wafer loading area.

[0022] A second aspect of the present invention provides a wafer loading apparatus, comprising:

[0023] Base;

[0024] The bracket is located above the base;

[0025] A detection component is arranged above the bracket. The detection component includes a rod that can move vertically and has a counterweight at its end.

[0026] A pressure detection port is provided above the bracket, and the counterweight is positioned corresponding to the pressure detection port. The rod is in different states depending on whether a wafer is loaded on it, and it can drive the counterweight to open or block the pressure detection port so as to determine whether a wafer is loaded by pressure changes.

[0027] In some embodiments, the detection assembly further includes a guide post disposed below the rod, with a spring sleeved on its outer periphery; the wafer loaded above the rod can overcome the spring force, causing the counterweight to move downward to block the pressure detection port.

[0028] In some embodiments, one end of the rod is provided with an inclined surface, and the other end is provided with a counterweight, with the guide post disposed between the inclined surface and the counterweight.

[0029] The beneficial effects of this invention include:

[0030] a. The rods of the detection component are in different states depending on whether a wafer is loaded on them. They can drive the counterweight to open or block the pressure detection port so as to determine whether the bracket is loaded with a wafer by the pressure change.

[0031] b. During in-situ testing, the pressure testing port will not come into contact with the wafer surface, effectively avoiding the impact of particulate matter contained in the pipeline on the wafer cleanliness;

[0032] c. The pressure detection port can be located near the edge of the bracket to reduce the space occupied inside the bracket, and also facilitate the daily cleaning and maintenance of the pressure detection port, effectively improving the ease of use. Attached Figure Description

[0033] The advantages of the present invention will become clearer and easier to understand through the following detailed description in conjunction with the accompanying drawings, which are merely illustrative and do not limit the scope of protection of the present invention, wherein:

[0034] Figure 1 This is a schematic diagram of a wafer loading apparatus provided in an embodiment of the present invention;

[0035] Figure 2 yes Figure 1 Top view of the corresponding wafer loading device;

[0036] Figure 3 This is a schematic diagram of a detection component provided in an embodiment of the present invention;

[0037] Figure 4 yes Figure 1A schematic diagram of the wafer placed on top of the support in the embodiment;

[0038] Figure 5 This is a schematic diagram of a wafer loading apparatus provided in another embodiment of the present invention;

[0039] Figure 6 This is a schematic diagram of a wafer loading apparatus provided in another embodiment of the present invention;

[0040] Figure 7 yes Figure 6 A schematic diagram of the wafer placed on top of the support in the embodiment;

[0041] Figure 8 This is a schematic diagram of a wafer loading apparatus provided in another embodiment of the present invention. Detailed Implementation

[0042] The technical solutions of the present invention will be described in detail below with reference to specific embodiments and accompanying drawings. The embodiments described herein are specific implementations of the present invention, used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary, and should not be construed as limiting the implementation of the present invention or the scope of protection of the present invention. In addition to the embodiments described herein, those skilled in the art can employ other obvious technical solutions based on the content disclosed in the claims and specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein.

[0043] The accompanying drawings in this specification are schematic diagrams used to illustrate the concept of the invention and to schematically show the shapes of the various parts and their interrelationships. It should be understood that, in order to clearly show the structure of the various components of the embodiments of the invention, the drawings are not drawn to the same scale, and the same reference numerals are used to indicate the same parts in the drawings.

[0044] In this invention, "Chemical Mechanical Polishing (CMP)" is also called "Chemical Mechanical Planarization (CMP)," and a wafer (W) is also called a substrate (Substrate), with equivalent meaning and practical function. The term "comprising" and similar expressions should be understood as open-ended inclusion, i.e., "including but not limited to." The term "based on" should be understood as "at least partially based on." The term "one embodiment" or "this embodiment" should be understood as "at least one embodiment." The terms "first," "second," etc., may refer to different or the same objects and are used only to distinguish the objects referred to, without implying a specific spatial order, temporal order, order of importance, etc., of the objects referred to. In some embodiments, values, processes, selected items, determined items, equipment, apparatus, means, parts, components, etc., are referred to as "best," "lowest," "highest," "minimum," "maximum," etc. It should be understood that such descriptions are intended to indicate that selection can be made from a number of available functional options, and that such selection is not necessarily better, lower, higher, smaller, larger, or otherwise preferred than other options in any other respect or in all respects.

[0045] Figure 1 This is a schematic diagram of a wafer loading apparatus 100 provided in an embodiment of the present invention. The wafer loading apparatus 100 includes:

[0046] The base 10 has a lifting drive device, such as a cylinder or electric cylinder, at its lower part to drive the base 10 and the components on it to move as a whole, so as to cooperate with the wafer and the carrier head or wafer handling robot to interact.

[0047] The bracket 20 is located above the base 10; typically, an elastic component with a buffer function is provided between the base 10 and the bracket 20, so that the wafer loading device 100 can interact with the carrier head; at the same time, the vertical positions of the base 10 and the bracket 20 are relatively fixed to ensure the accuracy of the interaction between the wafer loading device 100 and the robot arm.

[0048] A detection component 30 is configured above the tray 20, which is used to detect whether a wafer is placed on the tray 20, that is, for wafer in-situ detection.

[0049] In this invention, the detection component 30 includes a rod 31, which is capable of swinging up and down around a swing point L, and a counterweight 32 is provided at its end. Figure 3 As shown; if one end of the rod 31 is subjected to force, the rod 31 can drive the counterweight 32 to rotate up and down around the swing point L, thereby changing the vertical position of the counterweight 32.

[0050] Furthermore, a pressure detection port 21 is provided above the bracket 20, such as... Figure 1 As shown, the pressure detection port 21 cooperates with the detection component 30 to realize in-situ detection of the wafer.

[0051] Furthermore, the counterweight 32 is positioned corresponding to the pressure detection port 21. When the rod 31 is in different states depending on whether a wafer is loaded on it, it can drive the counterweight 32 to open or block the pressure detection port 21, so as to determine whether the bracket 20 is loaded with a wafer by the pressure change.

[0052] Figure 1 In the illustrated embodiment, the bracket 20 has a vertical channel 20a and a horizontal channel 20b inside. The vertical channel 20a is approximately located at the center of the bracket 20, and the vertical channel 20a is connected to a pipe ( Figure 1 (Indicated by the dashed line) It is connected to an external fluid source 50. A pressure sensor 40 is installed on the pipeline between the fluid source 50 and the vertical channel 20a to detect pressure changes in the pipeline.

[0053] It should be noted that multiple guide rods 80 are also provided above the bracket 20. The upper end of the guide rods 80 is rounded to guide the wafer to slide down from top to bottom onto the rod 31.

[0054] Figure 2 yes Figure 1 The wafer loading device 100 in this embodiment is shown in top view. The bracket 20 is also provided with a horizontal channel 20b, one end of which is connected to a vertical channel 20a, and the other end of which is connected to a pressure detection port 21. Specifically, a vertical hole 20c is provided at the end of the horizontal channel 20b (near the edge of the bracket 20), and the upper port of the vertical hole 20c is the pressure detection port 21.

[0055] Figure 2 In the middle, there are three transverse channels 20b, which form three pressure detection ports 21; correspondingly, three detection components 30 are arranged on the bracket 20. That is, the number of detection components 30 is equal to the number of pressure detection ports 21, so as to detect pressure changes through the pressure sensor 40 on the pipeline between the fluid source 50 and the vertical channel 20a.

[0056] As an embodiment of the present invention, the position where the rod 31 contacts the wafer W to be loaded is provided with an inclined surface 31a, such as... Figure 3 As shown, the contact area between the rod 31 and the wafer W is controlled to prevent excessive contact between the rod 31 and the edge of the wafer W, which could lead to scratches or introduce other particulate contaminants, thereby controlling the impact of the wafer loading process on the wafer processing quality.

[0057] Figure 3In this embodiment, the rod 31 may be provided with an inclined section, such that the edge of the wafer W contacts the inclined surface 31a formed by the inclined section of the rod 31, i.e., the contact is a line contact, and the length of the contact line segment is extremely small to prevent the wafer from being scratched or other contaminants from being introduced. As a variant of this embodiment, the top surface of the rod 31 is also directly provided with an inclined surface 31a to ensure line contact between the wafer and the rod 31.

[0058] Figure 2 In this design, there are three detection components 30, which are evenly distributed above the carrier 20 with the center of the wafer loading area as the reference. The counterweight 32 on the detection component 30 cooperates with the pressure detection port 21 on the carrier 20 to complete the in-situ detection of the wafer. It can be understood that there can be other numbers of detection components 30, and each detection component 30 is equipped with an independent pressure sensor 40 to determine whether the wafer is loaded by combining multiple detection points.

[0059] The following is combined Figure 1 and Figure 4 The following is a brief description of the steps for in-situ detection performed by the wafer loading apparatus 100 of the present invention:

[0060] Initially, no wafer W is placed on the tray 20, such as Figure 1 As shown; at this time, the counterweight 32 abuts against the top surface of the bracket 20 under the action of gravity, that is, the counterweight 32 blocks the pressure detection port 21 on the bracket 20; the fluid source 50 introduces fluid into the pipeline, and the pressure sensor 40 detects the pressure value P1 in the pipeline;

[0061] After wafer W is placed above bracket 20, guided by guide rod 80, the edge of wafer W presses against the top of rod 31; under the action of its own weight, rod 31 swings counterclockwise around swing point L, as... Figure 4 As shown, the counterweight 32 moves upward to disengage from the top surface of the bracket 20, thus opening the pressure detection port 21. At this time, the pressure sensor 40 detects a pressure value P2 in the pipeline.

[0062] By comparing the pressure changes in the pipeline, it can be determined whether the wafer W is placed on the tray 20. Specifically, if the pressure in the pipeline decreases, i.e., P2 < P1, then a wafer is placed on the tray 20; if the pressure value in the pipeline remains almost unchanged, then no wafer is placed on the tray 20.

[0063] The technical solution provided by this invention ensures that the wafer does not come into contact with the pressure detection port 21 on the carrier 20 during in-situ wafer inspection, thereby avoiding contamination of the wafer surface by the fluid in the pipeline. This helps maintain the cleanliness of the wafer surface and reduces the difficulty of subsequent wafer cleaning.

[0064] In order to ensure that the counterweight 32 can reliably block the pressure detection port 21, the bottom surface of the counterweight 32 is flat, so as to block the pressure detection port 21 on the bracket 20 when the wafer is not pressed against the rod 31.

[0065] Figure 1 In the embodiment shown, one end of the rod 31 is provided with an inclined surface 31a. Figure 3 As shown in the diagram, a counterweight 32 is configured at the other end of the bracket 20. Specifically, the counterweight 32 is positioned near the edge of the bracket 20, meaning the pressure detection port 21 is also positioned at the edge of the bracket 20. This configuration facilitates regular cleaning of the pressure detection port 21 and prevents a large amount of particulate matter from adhering to the top edge of the bracket 20, which could affect the accuracy of in-situ wafer detection.

[0066] Figure 5 This is a schematic diagram of a wafer loading apparatus 100 provided in another embodiment of the present invention, which is similar to... Figure 1 The embodiments shown are similar, and the differences between the two are briefly described below: the counterweight 32 of the detection component 30 is disposed near the inner side of the bracket 20, while the inclined surface that contacts the edge of the wafer is disposed near the edge of the bracket 20.

[0067] In this embodiment, the working principle of in-situ wafer detection is the same as... Figure 1 The illustrated embodiments are basically the same. When placing the wafer W on the bracket 20, the counterweight 32 of the rod 31 moves upward. It should be noted that in this embodiment, when the counterweight 32 moves upward, the top surface of the counterweight 32 cannot contact the back surface (the surface facing downward) of the wafer W to prevent the counterweight 32 from scratching the wafer or causing the wafer to shake on the bracket 20.

[0068] In another embodiment of the present invention, the detection component 30 is further configured with a spring 60, such as Figure 6 As shown. Spring 60 is positioned between the swing point L of rod 31 and configuration block 32; the wafer to be loaded is pressed against the outside of the position where spring 60 is located.

[0069] Figure 6 In this invention, the detection component 30 is positioned near the inner side of the tray 20; specifically, the detection component 30 is primarily located inside the wafer loading area. This solution can be adopted when the internal space of the tray 20 is relatively ample. In this invention, the wafer loading area refers to the circular area occupied by the wafer placed above the tray 20.

[0070] Specifically, after the wafer W is placed above the bracket 20, under the action of gravity, the wafer overcomes the elastic force of the spring 60 and presses the counterweight 32 against the top surface of the bracket 20 to block the pressure detection port 21. Figure 7 As shown, this causes pressure changes in the pipeline to determine whether the wafer has been successfully placed on the tray 20.

[0071] In this invention, the swing point of the rod 31 can be located inside the wafer loading area, such as... Figure 5 and Figure 6 The given embodiment; it can be understood that the swing point of the rod 31 can also be located outside the wafer loading area, such as Figure 1 The given embodiment. Comparing the two technical solutions, the solution of setting the swing point of the rod 31 on the outside of the wafer loading area is more advantageous. This is because the solution of setting the swing point of the rod 31 on the outside requires less space on the inside of the bracket 20. In addition, the detection component 30 is set towards the edge of the bracket 20, which helps to improve the convenience of operation and maintenance.

[0072] Furthermore, the present invention also provides a wafer loading device 110, which includes a base 10 and a bracket 20, such as... Figure 8 As shown, bracket 20 is located above base 10.

[0073] Furthermore, a detection component 30 is disposed above the bracket 20. The detection component 30 includes a rod 31, which is horizontally arranged and can move vertically. A counterweight 32 is disposed at its end.

[0074] The structure of bracket 20 and Figure 1 The illustrated embodiment is similar and will not be described again here. A pressure detection port 21 is provided above the bracket 20, and the position of the counterweight 32 corresponds to the pressure detection port 21.

[0075] In this embodiment, the rod 31 is in different states depending on whether a wafer is loaded on it. It can drive the counterweight 32 to open or block the pressure detection port so as to determine whether the bracket 20 is loaded with a wafer by the pressure change.

[0076] Furthermore, the detection assembly 30 also includes a guide post 70 disposed below the rod 31, and a spring 60 is sleeved on the outer periphery of the guide post 70; the wafer loaded above the rod 31 can overcome the elastic force of the spring 60, causing the counterweight 32 to move downward to block the pressure detection port 21 above the bracket 10, so that the pressure value on the pipeline connected to the fluid source 50 changes, in order to determine whether the wafer is placed on the bracket 20.

[0077] Furthermore, one end of the rod 31 is provided with an inclined surface 31a, such as... Figure 8 As shown, a counterweight 32 is provided at the other end, and a guide post 70 is provided between the inclined surface 31a and the counterweight 32. The wafer W placed above the bracket 20 can press against the inclined surface 31a of the rod 31.

[0078] Under the influence of the wafer W's own gravity, the rod 31 and the counterweight 32 move downward as a whole, causing the counterweight 32 to block the pressure detection port 21, thereby causing pressure changes in the pipeline. Its in-situ detection principle is similar to that of the above embodiment, and will not be repeated here.

[0079] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0080] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A method for in-situ wafer inspection, characterized in that, Testing is performed using a wafer loading device, including: When no wafer is placed on the tray, the counterweight blocks the pressure detection port on the tray, and fluid is introduced into the pipeline from the fluid source toward the tray. The pressure sensor detects the pressure in the pipeline as P1. After the wafer is placed on the tray, it is pressed against the top of the rod under the guidance of the guide rod; under the action of the wafer's own weight, the rod swings counterclockwise around the swing point, and the counterweight moves upward to detach from the top surface of the tray, so that the pressure detection port opens; the pressure sensor detects the pressure in the pipeline as P2; If P2 < P1, then a wafer is placed on the tray; if the pressure value on the pipeline remains unchanged, then no wafer is placed on the tray. The wafer loading device is equipped with a base and a bracket disposed above the base; A detection component is configured above the bracket, which includes a rod and a spring. The rod swings up and down around a fixed point. One end of the rod is provided with a counterweight, and the other end is provided with an inclined surface that contacts the edge of the wafer. The spring is located between the swing point of the rod and the counterweight. The wafer to be loaded is pressed against the outside of the spring's location. The swing point of the rod is located outside the wafer loading area. The bracket is provided with a pressure detection port on its edge; The bottom surface of the counterweight is a plane, which precisely corresponds to the position of the pressure detection port, and the bottom surface of the counterweight and the pressure detection port form a planar sealed contact.

2. The wafer in-situ inspection method as described in claim 1, characterized in that, As the rod is in different states depending on whether it is loaded with wafers, it drives the counterweight to open or block the pressure detection port, so as to determine whether the bracket is loaded with wafers by the pressure change.

3. The wafer in-situ inspection method as described in claim 1, characterized in that, The number of detection components is multiple, and they are evenly distributed above the tray with the center of the wafer loading area as the reference.

4. The wafer in-situ inspection method as described in claim 1, characterized in that, The detection assembly also includes a guide post disposed below the rod, with a spring sleeved on its outer periphery; the wafer loaded above the rod overcomes the elastic force of the spring, causing the counterweight to move downward to block the pressure detection port.

5. The wafer in-situ inspection method as described in claim 1, characterized in that, The bracket has a vertical channel inside, which is connected to an external fluid source through a pipe. A pressure sensor is installed on the pipe between the fluid source and the vertical channel.

6. The wafer in-situ inspection method as described in claim 5, characterized in that, The bracket is also equipped with a transverse channel, one end of which is connected to a vertical channel, and the other end of which is connected to a pressure detection port.

7. The wafer in-situ inspection method as described in claim 6, characterized in that, The number of transverse channels is three, and their upper ports form pressure detection ports; the number of detection components is equal to the number of pressure detection ports.

8. The wafer in-situ inspection method as described in claim 7, characterized in that, The detection components are evenly distributed above the tray with the center of the wafer loading area as the reference. The wafer loading area refers to the circular area occupied by the wafer placed above the tray.

9. The wafer in-situ inspection method as described in claim 4, characterized in that, One end of the rod is provided with an inclined surface, and the other end is provided with a counterweight. The guide post is located between the inclined surface and the counterweight.

10. The wafer in-situ inspection method as described in claim 1, characterized in that, The rod is set horizontally and moves vertically, so that the counterweight at the end of the rod opens or blocks the pressure detection port, and then the pressure value change on the pipeline connected to the fluid source is used to determine whether the wafer is placed on the bracket.

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