Device for dividing wafer into N parts with fixed size and working method thereof

Abstract

The invention relates to a device for dividing a wafer into N parts with fixed sizes and a working method thereof, and belongs to the field of semiconductor equipment, a round hole is formed in the top of a main frame, a cylinder is installed in the round hole, and an upper pressing head is installed at the end of a telescopic rod of the cylinder; fixing columns are arranged at the bottom of the fixing plate and used for installing lower pressing heads of different sizes. The fixed plate is installed in the main frame and located above the lower pressing head, a sinking area is arranged in the fixed plate, a hole is formed in the center of the sinking area, and the movable plate is placed in the sinking area of the fixed plate and can move in the sinking area; a through round hole is formed in the center of the movable plate, and a collapsing ring used for clamping a blue film is fixedly arranged on the round hole. According to the invention, the device assists manual work in separating wafers with fixed sizes, the crystal grains are directly adhered to the blue film, the adhesion effect is improved, rapid separation of the crystal grains can be realized, rapid film pouring of the separated single crystal grains can be realized, and the separation and film pouring efficiency of the cut single crystal grains can be improved.

Description

Technical Field

[0001] The present invention relates to a device for dividing a wafer into N parts of fixed size and a working method thereof, belonging to the technical field of semiconductor equipment, and in particular to a device for dividing a wafer into N parts of fixed size by film inversion, and capable of separating wafers of various sizes, wherein N is greater than or equal to 2. Background Art

[0002] In the production process of semiconductor wafers, multiple processes are required. After the wafers have passed the electrical performance test, the grains of different grades and performances are separated and attached to different blue films through a sorting machine. Then, the visual appearance inspection is carried out by quality inspectors, and then they are packaged and enter the next production link. The separated grains are selected by the crystal bonding machine and placed on the tray.

[0003] The existing method for separating wafers after sorting mainly adopts manual operation. The blue film with grains is placed with the grains facing up, and then three smooth non-stick plastic films are used on the surface of the grains to piece together the production specified size (that is, the side length is within a certain size range). Three plastic films are used to block the area outside this size, and then a blue film with stickiness downward is placed on the upper end. Then, these three layers are put into a laminator together, compacted into one piece, and then torn apart. In this way, the grains outside the area covered by the blue film are obtained, and the grains within a fixed size are separated. This method has low working efficiency, and a ruler needs to be used to measure whether it exceeds the specified size each time. After the operation is completed, the film used for blocking needs to be torn off, and the process is relatively cumbersome.

[0004] Therefore, there is a need for a device that can assist manual separation of wafers of fixed sizes.

[0005] Chinese patent document CN 111509107A (application number: 202010333331.2) discloses a method for separating N parts of LED wafers into inverted films, which belongs to the field of semiconductor inverted film technology, and includes the following steps: S1. The crystal on the carrier large blue film is separated into multiple single grains by equipment, and the back of the crystal is glued to the carrier large blue film; S2. A partition with an area larger than the total area of ​​the crystal before cutting is covered on the front of the product after cutting, at which time the back of the partition fits the front of the single grain, and at the same time, a single grain after cutting is aligned with the through hole on the partition, and the other single grains on the carrier large blue film are blocked by the partition; S3. A transition carrier film that is more than 2 cm larger than the periphery of the through hole port is glued to the front of the partition, so that the transition carrier film covers the through hole port. This method may affect the effect of the blue film adhering to the grain due to the thickness of the cover plate or the shielding film. Because when the thickness of the cover plate or the shielding film is too large, the shovel cannot press the grains in the area to be removed, and a good contact effect cannot be achieved. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention provides a device for dividing a wafer into N portions of fixed size and a working method thereof, and a device for assisting manual separation of wafers of fixed size. The crystal grains are directly adhered to the blue film, which improves the adhesion effect and can achieve rapid separation of the crystal grains, and rapid film inversion of the single crystal grains after separation, thereby improving the separation of the single crystal grains after cutting and the efficiency of film inversion.

[0007] The technical solution of the present invention is as follows:

[0008] A device for dividing a wafer into N pieces of fixed size, used for separating qualified grains with the same performance after the wafer manufacturing sorting process, comprising a main frame, a cylinder, a fixed plate, a movable plate, an upper pressure head and a lower pressure head. The main frame is a rectangular parallelepiped structure with the front and rear surfaces removed. A circular hole is provided on the top of the main frame, in which a cylinder is installed. An upper pressure head is installed at the end of the telescopic rod of the cylinder, and the upper pressure head can move up and down under the drive of the cylinder.

[0009] The bottom of the fixed plate is provided with a protruding fixed column for installing pressing heads of different sizes; the fixed plate is installed in the main frame and is located above the pressing head, a sinking area is provided inside the fixed plate, a hole is provided in the center of the sinking area, so that the wafer on the blue film on the collapse ring can contact the pressing head, and the movable plate is placed in the sinking area of ​​the fixed plate and can move in the sinking area; the purpose of setting the sinking area is to facilitate the movable plate to move freely within its range, and the movable movable plate is used to confirm the film pressing area between the blue film on the collapse ring and the surface light source of the pressing head;

[0010] A through circular hole is arranged at the center of the movable plate, and a collapse ring for clamping the blue film is fixedly arranged on the circular hole. The diameter of the circular hole is slightly smaller than the diameter of the collapse ring to prevent the collapse ring from falling due to excessive diameter.

[0011] Preferably, the surface of the lower pressure head is provided with a light source to facilitate confirmation of the grains in the area to be separated. The lower pressure head can be understood as a square pressure head with arc treatment on all sides and a light source on the middle plane part. The lower pressure head can be disassembled and replaced, and the upper pressure head is a plane slightly larger than the lower pressure head. When working, it mainly relies on the plane of the lower pressure head surface and the extrusion of the top pressure head. At this time, the force-bearing area will be limited to the plane part of the lower pressure head surface, and the rest of the part cannot be subjected to force with the top pressure head, so only the grains within the plane area of ​​the lower pressure head can be adhered to another blue film by extrusion.

[0012] Preferably, the upper pressure head is a silicone disc, which can achieve a better extrusion effect when extruded with the lower pressure head and has a certain buffering performance to avoid damaging the wafer.

[0013] Preferably, a threaded hole is provided on the side of the pressing head, and the pressing head is fixed to the fixing column by screws. The side of the fixing column inside is clamped by screwing in the screws, and when replacing, only the screws need to be loosened.

[0014] Preferably, the sunken area is formed by digging out a portion of the thickness inside the fixing plate, and the removed thickness is half of the thickness of the fixing plate.

[0015] Preferably, the collapse ring includes an inner ring and an outer ring which are nested with each other, the inner ring and the outer ring are used to clamp the blue film, the blue film is sandwiched between the two circular rings, and a wafer is adhered to the surface of the blue film. Three limiting columns for fixing the collapse ring are arranged around the circular hole of the movable plate, which cooperate with the groove of the collapse ring to achieve precise positioning.

[0016] The main principle of the invention is to push the upper pressure head through the cylinder to extrude with the lower pressure head, squeeze the two blue films together and then tear them apart, so that the grains on one film adhere to the sticky side of the other blue film.

[0017] Preferably, the edge of the sinking area is provided with scales, which can be used to assist experience and memory.

[0018] A working method of the above-mentioned device for dividing a wafer into N pieces of fixed size comprises the following steps:

[0019] (1) The initial state is that the cylinder is retracted and the upper pressure head is at the top;

[0020] (2) During operation, the blue film with chip grains is fixed on the collapse ring using a film expansion machine, the collapse ring is fixed on the movable plate, and the position is limited by the limit column so that it is located at the center of the movable plate;

[0021] (3) Manual movable plate, the movable plate moves in the sinking area of ​​the fixed plate, and the area to be pressed is confirmed by the light source on the surface of the lower pressure head. The luminous area of ​​the lower pressure head is the area where the film can be pressed. The area without light source and the upper pressure head cannot be subjected to force during extrusion, so only the luminous part in the middle of the lower pressure head can be operated, and the range of each operation will not be larger than the luminous area, which well ensures that the size will not exceed when the grains are separated;

[0022] (4) After confirming the area, place a blue film with sticky downward (i.e., the target for the grains to adhere) on the broken ring, press the cylinder switch, and the upper pressure head moves downward through the cylinder until it contacts the lower pressure head (the pressure is between 5-10Mpa). The two blue films are squeezed together, and the upper layer of blue film is manually peeled off. In this way, a part of the grains of the lower pressure head surface area is peeled off from the blue film with grains below, completing a working cycle.

[0023] The present invention separates the crystals by the ejection effect of the lower pressure head, which can solve the influence of the thickness of the covering method on the pressing effect, and can adapt to the wafer separation size with different requirements by replacing the lower pressure head.

[0024] The beneficial effects of the present invention are:

[0025] 1. The present invention replaces manual film pasting for size positioning, and solves the problems of different film pasting angles and exceeding the limit size between different employees. The present invention can complete wafer separation quickly and accurately without error when the downward pressure head is determined, and standardizes the operation procedure.

[0026] 2. The present invention can meet the requirements of different sizes by replacing the lower pressure head, and has a wide range of applications and strong versatility.

[0027] 3. The present invention adopts an ejection extrusion method, and the wafer in the operating area is lifted up by the downward pressure head. There are no other objects in the middle, and the grains are directly adhered to the blue film, which improves the adhesion effect and solves the current operation method of covering the surface of the grains during separation (adding a layer of covering between the two films will affect the adhesion effect of the wafer in the hole of the covering).

[0028] 4. The surface of the lower pressure head is equipped with a light source, which can simplify the personnel's confirmation of the grains in the area to be separated.

[0029] 5. The edge of the sinking area of ​​the present invention is provided with scales. When a single product is used for a long time, the scale at which the movable plate is located during each separation can be manually memorized, thereby further improving work efficiency.

[0030] 6. The present invention has a simple structure, low equipment cost, simple later maintenance, and low repair cost, and is suitable for mass production and investment in the semiconductor industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The drawings in the specification, which constitute a part of the present application, are used to provide further understanding of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute improper limitations on the present application.

[0032] Figure 1 An axonometric diagram of a device for dividing a wafer into N pieces of fixed size according to the present invention;

[0033] Figure 2 This is a schematic diagram of the decomposition of the collapse ring and the movable plate;

[0034] Figure 3 It is the front and side view of the collapse ring and the movable plate;

[0035] Figure 4 It is a schematic diagram of the structure of the lower pressure head;

[0036] Figure 5 It is a top view of the fixed plate;

[0037] In the figure, 1-main frame, 2-cylinder, 3-fixed plate, 4-movable plate, 5-upper pressure head, 6-lower pressure head, 7-fixed column, 8-hole, 9-broken ring, 10-threaded hole, 11-limiting column, 12-cylinder switch, 13-chip grain. DETAILED DESCRIPTION

[0038] In order to enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of the present invention are clearly and completely described, but not limited to this. Anything not fully described in the present invention shall be based on conventional techniques in the art.

[0039] Example 1

[0040] A device for dividing a wafer into N pieces of fixed size, such as Figures 1 to 5 As shown, it includes a main frame 1, a cylinder 2, a fixed plate 3, a movable plate 4, an upper pressure head 5 and a lower pressure head 6. The main frame 1 is a rectangular parallelepiped structure with the front and rear surfaces removed. A circular hole is opened on the top of the main frame 1, and the cylinder 2 is installed in the circular hole. The upper pressure head 5 is installed at the end of the telescopic rod of the cylinder. The upper pressure head 5 can move up and down under the drive of the cylinder 2;

[0041] A protruding fixed column 7 is provided at the bottom of the fixed plate 3 for installing the pressing heads 6 of different sizes; the fixed plate 3 is installed in the main frame 1 and is located above the pressing head 6, and a sinking area is provided inside the fixed plate 3, and a hole 8 is provided in the center of the sinking area, so that the wafer on the blue film on the collapse ring can contact with the pressing head, and the movable plate 4 is placed in the sinking area of ​​the fixed plate and can move in the sinking area; the purpose of setting the sinking area is to facilitate the movable plate to move freely within its range, and the movable movable plate is used to confirm the film pressing area between the blue film on the collapse ring and the surface light source of the pressing head;

[0042] A through circular hole is arranged at the center of the movable plate 4, on which a collapse ring 9 for clamping the blue film is fixedly arranged, and the diameter of the circular hole is slightly smaller than the diameter of the collapse ring 9 to prevent the collapse ring from falling due to excessive diameter.

[0043] Example 2

[0044] A device for dividing a wafer into N pieces of fixed size, as described in Example 1, except that a light source is provided on the surface of the pressing head 6 to facilitate identification of the grains in the area to be separated. Figure 4As shown, the lower pressure head 6 can be understood as a square pressure head with arc treatment on all sides and a light source on the middle plane part. The lower pressure head can be disassembled and replaced, and the upper pressure head is a plane slightly larger than the lower pressure head. When working, it mainly relies on the plane surface of the lower pressure head and the extrusion of the top pressure head. At this time, the force area will be limited to the plane part of the lower pressure head surface, and the rest of the part cannot be subjected to force with the top pressure head, so only the grains within the plane area of ​​the lower pressure head can be extruded and adhered to another blue film.

[0045] The upper pressing head 5 is a silicone disc, which can achieve a better pressing effect when pressed with the lower pressing head, and has a certain buffering performance to avoid damaging the wafer.

[0046] A threaded hole 10 is provided on the side of the pressing head 6, and the pressing head 6 is fixed to the fixing column 7 by screws. The side of the fixing column inside is clamped by screwing in the screws, and when replacing, only the screws need to be loosened.

[0047] The sunken area is formed by digging out part of the thickness inside the fixed plate, and the thickness of the digging out is half of the thickness of the fixed plate.

[0048] The broken ring 9 includes an inner ring and an outer ring which are nested with each other. The inner ring and the outer ring are used to clamp the blue film. The blue film is sandwiched between the two circular rings. A wafer is adhered to the surface of the blue film. Three limiting columns 11 for fixing the broken ring are arranged around the circular hole of the movable plate, which cooperate with the groove of the broken ring to achieve precise positioning.

[0049] The main principle of the invention is to push the upper pressure head through the cylinder to extrude with the lower pressure head, squeeze the two blue films together and then tear them apart, so that the grains on one film adhere to the sticky side of the other blue film.

[0050] The edge of the sunken area is provided with scales, which can be used to assist with experience and memory.

[0051] Example 3

[0052] A working method of a device for dividing a wafer into N pieces of fixed size comprises the following steps:

[0053] (1) The initial state is that the cylinder 2 is retracted and the upper pressure head 5 is at the top;

[0054] (2) During operation, the blue film with the chip grains 13 is fixed on the collapse ring 9 by using a film expansion machine, and the collapse ring 9 is fixed on the movable plate 4, and the position is limited by the limiting column 11 so that it is located at the center of the movable plate;

[0055] (3) Manually move the movable plate 4, which moves in the sinking area of ​​the fixed plate, and confirms the area to be pressed by the light source on the surface of the lower pressure head 6. The luminous area of ​​the lower pressure head is the area where the film can be pressed. The area without light source and the upper pressure head cannot be subjected to force during extrusion, so only the luminous part in the middle of the lower pressure head can be operated, and the range of each operation will not be larger than the luminous area, which well ensures that the size will not exceed when the grains are separated;

[0056] (4) After confirming the area, place a blue film with stickiness downward (i.e., the target to which the grains are to adhere) on the broken ring 9, press the cylinder switch 12, and the upper pressure head moves downward through the drive of the cylinder 2 until it contacts the lower pressure head (the pressure is between 5-10Mpa). The two blue films are squeezed together, and the upper layer of blue film is manually peeled off. In this way, a part of the grains of the same size as the surface of the lower pressure head are peeled off from the blue film with grains below, completing a working cycle.

[0057] Comparative Example:

[0058] A method for separating LED wafers into N pieces by flipping a film, which uses a cover plate to cover the holes, and uses a shovel to press at a 45° angle. During operation, the cover plate covers the surface of the grain, exposing a portion of the grain. This method may affect the effect of the blue film adhering to the grain due to the thickness of the cover plate or the shielding film. Because when the thickness of the cover plate or the shielding film is too large, the shovel cannot press the grain in the area to be removed, and a good contact effect cannot be achieved.

[0059] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A device for dividing a wafer into N pieces of fixed size, characterized in that: It includes a main frame, a cylinder, a fixed plate, a movable plate, an upper pressure head and a lower pressure head. A circular hole is opened on the top of the main frame, and a cylinder is installed in the circular hole. The upper pressure head is installed at the end of the telescopic rod of the cylinder. A fixing column is provided at the bottom of the fixed plate for installing pressure heads of different sizes; the fixed plate is installed in the main frame and located above the pressure head, a sinking area is provided inside the fixed plate, a hole is provided in the center of the sinking area, and the movable plate is placed in the sinking area of ​​the fixed plate and can move in the sinking area; A penetrating circular hole is arranged at the center of the movable plate, and a collapse ring for clamping the blue film is fixedly arranged on the circular hole, and the diameter of the circular hole is smaller than the diameter of the collapse ring.

2. The device for dividing a wafer into N pieces of fixed size according to claim 1, characterized in that: The surface of the lower pressure head is provided with a light source, which is convenient for confirming the grains in the area to be separated.

3. The device for dividing a wafer into N pieces of fixed size according to claim 2, characterized in that: The upper pressure head is a silica gel disc.

4. The device for dividing a wafer into N pieces of fixed size according to claim 3, characterized in that: A threaded hole is arranged on the side of the pressing head, and the pressing head is fixed to the fixing column by screws.

5. The device for dividing a wafer into N pieces of fixed size according to claim 4, characterized in that: The sunken area is formed by digging out a portion of the thickness inside the fixed plate, and the removed thickness is half of the thickness of the fixed plate.

6. The device for dividing a wafer into N pieces of fixed size according to claim 5, characterized in that: The collapse ring comprises an inner ring and an outer ring which are nested with each other, and the inner ring and the outer ring are used to clamp the blue film. Three limiting columns for fixing the collapse ring are arranged around the circular hole of the movable plate.

7. The device for dividing a wafer into N pieces of fixed size according to claim 6, characterized in that: The edge of the sinking area is provided with scales.

8. A working method of the device for dividing a wafer into N pieces of fixed size based on claim 7, characterized in that: The steps include: (1) The initial state is that the cylinder is retracted and the upper pressure head is at the top; (2) During operation, the blue film with chip grains is fixed on the collapse ring using a film expansion machine, the collapse ring is fixed on the movable plate, and the position is limited by the limit column so that it is located at the center of the movable plate; (3) Manually move the movable plate, which moves in the sunken area of ​​the fixed plate, and confirms the area to be pressed by the light source on the surface of the lower pressure head; (4) After confirming the area, place a blue film with the sticky side facing downward on the broken ring, press the cylinder switch, and the upper pressure head moves downward through the drive of the cylinder until it contacts the lower pressure head. The two blue films are squeezed together, and the upper layer of blue film is manually peeled off to complete a working cycle.

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