Wafer positioning method for a thinning machine apparatus

Abstract

The application relates to a thinning machine device and a wafer positioning method. The thinning machine device comprises a device body, a positioning structure and a moving table. The positioning structure is fixed on the device body, and the moving table is located below the positioning structure. The positioning structure comprises at least a fixed part and a positioning part. The positioning part is fixed on the fixed part, and the positioning part is used for positioning the wafer position. The moving table comprises moving parts and a bearing part. The bearing part is arranged between the two moving parts. The moving parts are used for driving the bearing part to move laterally. The application has the advantages of low cost, convenient installation, simple and fast positioning process and higher positioning precision.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of integrated circuits, in particular to a thinning machine and wafer positioning method. BACKGROUND

[0002] In the semiconductor field, wafer thinning has been relatively mature after years of development, and wafer thinning equipment has also become more and more mature, but the process direction of using a wafer thinning machine to edge grind a wafer has not yet been developed.

[0003] However, in the wafer edge grinding process, the relative concentricity of the rotating platform and the wafer needs to be ensured, and currently, the positioning tool and the ceramic suction cup are used for positioning, and then the three claws are used for synchronous centripetal movement to push the wafer to the relative concentricity of the ceramic suction cup.

[0004] However, the existing technology has the following disadvantages:

[0005] 1. Complex operation, positioning tool needs to be placed each time;

[0006] 2. Low positioning accuracy, because the positioning tool first needs to be matched with the ceramic suction cup, and then the positioning tool claw movement process will produce various movement precision deviations.

[0007] The above two factors superimpose to cause low overall positioning accuracy. SUMMARY

[0008] In view of the above-mentioned shortcomings, the present application aims to solve the problem of ensuring the relative concentricity of the rotating platform and the wafer. Based on this, it is necessary to provide a thinning machine and wafer positioning method for the above-mentioned technical problems.

[0009] The present application provides a thinning machine, which comprises a device body, a positioning structure and a moving table, the positioning structure is fixed on the device body, and the working position is below the positioning structure; wherein,

[0010] The positioning structure comprises a fixed part and a positioning part, the positioning part is fixed on the fixed part, and the positioning part is used for positioning the position of the wafer;

[0011] The moving table comprises a moving part and a bearing part, the bearing part is arranged between the two moving parts, and the moving part is used for driving the bearing part to move laterally.

[0012] As an alternative embodiment, the positioning part comprises a positioning claw and a positioning finger arranged at the end of the positioning claw;

[0013] The fixed part comprises vertical fixed plates and horizontal fixed plates which are detachably fixed as a whole structure, the positioning part is fixed on the horizontal fixed plate, and the vertical fixed plate is fixed on the thinning machine.

[0014] As an alternative embodiment, the positioning fingers have tangent cylinders which are located at the ends of the positioning fingers and are detachably fixed on the positioning claws.

[0015] As an alternative embodiment, the positioning claws are fan-shaped and comprise a connecting plate, a supporting rod and two connecting rods, one end of each connecting rod is fixed with a positioning finger, the other end of each connecting rod is fixed with the connecting plate, the two ends of the supporting rod are fixed on the middle parts of the connecting rods, and the connecting plate is detachably fixed on the horizontal fixed plate.

[0016] As an alternative embodiment, the fixed part further comprises side plates which are arranged on the two sides of the horizontal fixed plate.

[0017] As an alternative embodiment, the bearing part comprises a workbench and a suction disc fixed on the workbench, and the wafer is vacuum adsorbed on the suction disc.

[0018] The present application provides a wafer positioning method for the above-mentioned thinning machine, which comprises the following steps:

[0019] Determining the center of the wafer to be processed;

[0020] Determining the target position of the moving table, calculating the moving distance of the moving table, and adjusting the moving table to move to the target position;

[0021] Placing the wafer to be processed on the suction disc of the moving table, and the wafer is tangent to the positioning fingers;

[0022] Completing the positioning of the wafer to be processed, and the wafer to be processed is concentric with the suction disc.

[0023] As an alternative embodiment, the target position is such that the distance between the center of the suction disc and the center of the tangent cylinder of the two positioning fingers is equal to the sum of the radius of the wafer to be processed and the radius of the tangent cylinder of the positioning fingers.

[0024] As an alternative embodiment, the movement of the moving table is linear movement, and the line connecting the intersection of the center of the suction disc and the two connecting rods of the positioning claws is the transverse direction of the moving table.

[0025] As an alternative embodiment, the moving distance is the distance between the center of the suction disc at the initial position and the center of the suction disc at the target position in the transverse direction of the moving table.

[0026] The thinning machine device and wafer positioning method can realize the positioning of the wafer in the edge grinding process of the thinning machine by adding the positioning gripper mechanism in the thinning machine. BRIEF DESCRIPTION OF DRAWINGS

[0027] Fig. 1 Figure 1 is a structural schematic diagram of the thinning machine device of the present application;

[0028] Fig. 2 Figure 2 is a structural schematic diagram of the positioning structure of the present application;

[0029] Fig. 3 Figure 3 is a calculation schematic diagram of the positioning method of the present application. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the present application more clear, the technical scheme in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0031] The embodiments of the present application, examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The terms "first", "second", "third" and the like (if present) in the description and claims of the present application and the drawings are used to distinguish similar objects, and do not necessarily describe a particular order or sequence. It should be understood that the described objects can be interchanged under appropriate circumstances. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. The direction terms mentioned in the present application, such as: up, down, left, right, front, back, inner, outer, side, etc. are only the direction of the drawings. The embodiments described below by reference to the drawings are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application. In addition, the present application repeatedly refers to numbers and / or letters in different examples. Such repetition is for the purpose of simplification and clarity, and does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the present application provides examples of various specific processes and materials, but those skilled in the art can realize the application of other processes and / or the use of other materials.

[0032] The present application provides a thinning machine device, such as Figs. 1-2As shown, the thinning machine device comprises a device body (not shown), a positioning structure 10 fixed on the device body of the thinning machine, and a moving table 20 located below the positioning structure.

[0033] The positioning structure 10 comprises at least a fixed part 30 and a positioning part 40 fixed on the fixed part 30, and the positioning part 40 is used for positioning the position of the wafer.

[0034] Further, the fixed part 30 comprises a vertical fixed plate 31 and a horizontal fixed plate 32, which are detachably fixed as an integral structure, the positioning part 40 is fixedly installed on the horizontal fixed plate 32, and the vertical fixed plate 31 is fixedly installed on the thinning machine device.

[0035] Preferably, the fixed part 30 further comprises side plates 33, and two side plates 33 are respectively arranged on the two sides of the horizontal fixed plate 32. The two side plates 33 form a space with the horizontal fixed plate 32, and the positioning part 40 is fixedly connected with the fixed part 30 in the space.

[0036] The positioning part 40 comprises a positioning hand claw 41 and a positioning finger 42 arranged at the end of the positioning hand claw 41.

[0037] Preferably, the positioning finger 42 has a structure of a tangent cylinder 421 located at the end of the positioning finger 42, and the positioning finger 42 is detachably installed on the positioning hand claw 41.

[0038] Further, the bottom surface of the positioning finger 42 is a horizontal surface, the bottom surface of the tangent cylinder 421 is flush with the bottom surface of the positioning finger 42, and the tangent cylinder 421 is higher than the positioning finger 42.

[0039] The positioning hand claw 41 comprises a connecting plate 411, a supporting rod 412, and two connecting rods 413, one end of each connecting rod 413 is fixed with one positioning finger 42, the other end of each connecting rod 413 is fixed with the connecting plate 411, the two ends of the supporting rod 412 are fixed at the middle part of the connecting rods 413, and the connecting plate 411 is detachably installed and fixed on the horizontal fixed plate 32.

[0040] Preferably, the connecting plate 411 is slidably installed on the horizontal fixed plate 32, and the two side plates 33 form direction guides.

[0041] Further, two fixing grooves are arranged on the connecting plate 411, and the positioning part 40 is fixed on the fixed part by installing bolts in the fixing grooves. Preferably, the fixing grooves are long strips, and the length direction of the fixing grooves is consistent with the length direction of the side plates 33, so that the position of the positioning part 40 can be adjusted in the length direction.

[0042] Further, the connecting plate 411 is provided with a mounting groove, through which the horizontal fixing plate 32 can be mounted on the vertical fixing plate 31.

[0043] Further, the two connecting rods 413 form a fan shape, and an angle is formed between the two connecting rods 413, and the extension lines of the two connecting rods 413 intersect at a point.

[0044] The mobile station 20 comprises mobile parts 21 and a bearing part 22, the bearing part 22 is arranged between the two mobile parts 21, and the mobile parts 21 are used to drive the bearing part 22 to move laterally.

[0045] Further, the bearing part 22 comprises a workbench 221 and a suction disc 222 fixed on the workbench 221, and the wafer is vacuum adsorbed on the suction disc 222.

[0046] Preferably, the suction disc 222 is a ceramic suction disc, and wafers 1 of different sizes can be placed on the suction disc 222. The workbench 221 can move laterally relative to the positioning part 40.

[0047] Preferably, the mobile part 21 comprises an organ protective cover, and the two ends of the workbench 221 are respectively connected to the organ protective cover of one mobile part 21.

[0048] In another embodiment, the vertical fixing plate 31 is an L-shaped connecting plate, the horizontal fixing plate 32 and the side plate 33 form an I-shaped connecting plate, the I-shaped connecting plate is mounted and fixed on the L-shaped connecting plate, and the connecting plate 411 of the positioning part 40 is mounted and fixed on the I-shaped connecting plate.

[0049] The wafer positioning method of the wafer thinning machine device can be used to position the wafer in the wafer thinning machine edge grinding process.

[0050] In another embodiment, the wafer positioning method of the wafer thinning machine device is provided, which comprises the following steps:

[0051] S10, determining the center of the wafer 1 to be processed;

[0052] S20, determine the target position of the working table 221 of the moving table 20, calculate the moving distance of the working table 221 of the moving table 20, adjust the position of the moving table 20, and move it to the target position;

[0053] S30, place the wafer 1 to be processed on the suction cup 222 of the moving table 20, at this time, the wafer to be processed is tangent to the tangent cylinder 421 of the positioning finger 42 of the positioning structure 10;

[0054] S40, complete the positioning of the wafer 1 to be processed, at this time, the wafer 1 to be processed is concentric with the suction cup 222.

[0055] Specifically, the target position in step S20 is that the distance between the center of the suction cup 222 and the center of the tangent cylinder 421 of the two positioning fingers 42 is equal to the sum of the radius of the wafer 1 to be processed and the radius of the tangent cylinder 421 of the positioning finger 42.

[0056] The moving distance in step S20 is the distance between the center of the suction cup 222 at the initial position and the center of the suction cup 222 at the target position in the horizontal moving direction of the moving table 20.

[0057] Further, the movement of the moving table 20 is linear movement, and the line connecting the intersection of the center of the suction cup 222 and the two connecting rods 413 of the positioning finger 41 is the horizontal moving direction of the moving table 20.

[0058] When different sizes of wafers 1 to be processed need to be placed, the control module of the thinning machine device drives the working table 221 of the moving table 20 to move and stop at the target position calculated in advance, at which the distance between the center of the suction cup 222 and the center of the tangent cylinder 421 of the two positioning fingers 52 is equal to the sum of the radius of the wafer 1 to be processed and the radius of the tangent cylinder 421 of the positioning finger 52.

[0059] After the moving table 20 completes the movement, the wafer 1 to be processed is placed on the suction cup 222, so that the wafer 1 to be processed is tangent to the tangent cylinder 421 of the positioning finger 52. At this time, the wafer 1 to be processed is concentric with the suction cup 222.

[0060] Specifically, as a specific example, as shown in Fig. 3 .

[0061] A and B are the center points of the two tangent cylinders 421, the radius of the tangent cylinder 421 is 4mm, the length of the line AB is 218.5mm, C is the center of the wafer 1 to be processed, the diameter of the wafer 1 to be processed is 305mm, D is the center of the suction cup 222, the diameter of the suction cup 222 is 330mm, C and D are on a horizontal line, O is the vertical intersection point of C and AB. Therefore,

[0062] AB = 218.5mm

[0063] AO = BO = 218.5 ÷ 2 = 109.25mm

[0064] AC = BC = (305 ÷ 2) + 4 = 156.5mm

[0065] AD = BD = (330 ÷ 2) + 4 = 169mm

[0066] According to the Pythagorean theorem:

[0067] OC = 109.25mm 112.0566mm

[0068] OD = 128.9396mm 128.9396mm

[0069] CD = OD - CD = 128.9396 - 112.0566 = 16.883 ≈ 17mm

[0070] Therefore, the lateral movement distance of the mobile station 20 is 17mm.

[0071] The wafer positioning method of the present application uses the positioning principle of three-point circle positioning to fix the center of the wafer, and drives the center of the chuck and the wafer to be concentric by adjusting the center of the chuck carrying the wafer. Therefore, the wafer positioning method of the present application can realize accurate positioning of the wafer to be processed.

[0072] It should be understood that although the steps are shown in sequence, these steps are not necessarily executed in sequence. Unless explicitly stated herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences.

[0073] The thinning machine device in the wafer positioning method can refer to the definition of the thinning machine device in the above, which will not be repeated here.

[0074] The thinning machine device and wafer positioning method of the present application use two positioning jaws of the positioning jaw mechanism to position the center of the wafer; use the lateral movement of the workbench to adjust the center of the chuck; in the case of determining the center of the wafer, adjust the center of the chuck to make the chuck and the wafer concentric; by adding the positioning jaw mechanism in the thinning machine, the positioning of the wafer in the edge grinding process of the thinning machine can be realized. The technical scheme of the thinning machine device and wafer positioning method of the present application has low implementation cost, is easy to install, has simple and fast positioning process, and has higher positioning accuracy.

[0075] Any combination of the technical features in the above-described embodiments can be made, and for the sake of brevity, not all possible combinations are described, however, as long as there is no conflict, any combination of the technical features should be considered within the scope of the present disclosure.

[0076] The above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be pointed out that, for ordinary skilled persons in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims.

Claims

1. A wafer positioning method for a thinning machine, characterized in that, the thinning machine comprises a machine body, a positioning structure and a moving table, the positioning structure is fixed on the machine body, and the moving table is located below the positioning structure; wherein, the positioning structure comprises at least a fixed part and a positioning part, the positioning part is fixed on the fixed part, and the positioning part is used for positioning the wafer position; the moving table comprises moving parts and a bearing part, the bearing part is arranged between the two moving parts, and the moving parts are used to drive the bearing part to move laterally; the positioning part comprises a positioning hand claw and a positioning finger arranged at the end of the positioning hand claw; the fixed part comprises a vertical fixed plate and a horizontal fixed plate, the vertical fixed plate and the horizontal fixed plate are detachably fixed as an integral structure, the positioning part is fixed on the horizontal fixed plate, and the vertical fixed plate is fixed on the machine body; the wafer positioning method comprises: determining the center of the wafer to be processed; determining the target position of the moving table, calculating the moving distance of the moving table, and adjusting the moving table to move to the target position; placing the wafer to be processed on the suction cup of the moving table, and the wafer is tangent to the positioning finger; completing the positioning of the wafer to be processed, and the wafer to be processed is concentric with the suction cup.

2. The wafer positioning method of a thinning apparatus according to claim 1, wherein The positioning finger has a tangent cylinder, the tangent cylinder is located at the end of the positioning finger, and the positioning finger is detachably mounted on the positioning hand claw.

3. The wafer positioning method of a thinning apparatus according to claim 2, wherein The positioning hand claw comprises a connecting plate, a supporting rod and two connecting rods, one end of each connecting rod is fixed with a positioning finger, the other end of each connecting rod is fixed with the connecting plate, and the two ends of the supporting rod are fixed on the middle part of the connecting rods, and the connecting plate is detachably mounted on the horizontal fixed plate.

4. The wafer positioning method of a thinning apparatus according to claim 1, wherein The fixed part further comprises side plates, and two side plates are arranged on the two sides of the horizontal fixed plate.

5. The wafer positioning method of a thinning apparatus device according to claim 1, wherein, The bearing part comprises a workbench and a suction cup fixed on the workbench, and the wafer is vacuum adsorbed on the suction cup.

6. The wafer positioning method of a thinning apparatus according to claim 1, wherein The target position is that the distance between the center of the suction cup and the center of the tangent cylinder of the two positioning fingers is equal to the sum of the radius of the wafer to be processed and the radius of the tangent cylinder of the positioning finger.

7. The wafer positioning method of a thinning apparatus according to claim 6, wherein The moving table moves in a straight line, and the connecting line between the center of the suction cup and the intersection of the two connecting rods of the positioning hand claw is the transverse direction of the moving table.

8. The wafer positioning method of a thinning apparatus according to claim 6, wherein The moving distance is the distance between the center of the suction cup at the initial position and the center of the suction cup at the target position in the transverse direction of the moving table.

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