Device and method for picking up crystal grains

Abstract

The present invention provides a device and method for picking up grains, the device comprising: a carrier, comprising a horizontal surface for placing grains; a push element arranged in the carrier, comprising a pin that can switch between extended and retracted states in a direction perpendicular to the horizontal surface; when the pin is in an extended state, the top of the pin is higher than the horizontal surface and can be fixed at multiple height positions; a vacuum clamp for clamping the grains from the carrier, which is arranged above the carrier. The present invention optimizes and adjusts the device and process for picking up grains of large-size chips, thereby ensuring that the process for picking up grains of large-size chips has a high success rate; a multi-stage lifting pin design is adopted, and by adjusting the lifting height and dwell time of the pin, it is ensured that the vacuum clamp can successfully pick up large-size chip grains.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor packaging technology, and in particular to a crystal grain picking device and method. Background Art

[0002] With the development of information technology, the requirements for chip performance and integration are increasing. In the fields of automotive chips, large-size chips have been widely used and have good development prospects.

[0003] At present, in the packaging process of large-size chips, the success rate of chip die pick-up is one of the important factors affecting the yield and cost of the packaging process. If abnormal conditions such as die drop or deviation occur during die pick-up, the die cannot be packaged normally in different packaging stations, and may even break and become scrapped.

[0004] However, for large-sized chip dies, since their size and quality exceed the specifications of existing chip dies, it is difficult to ensure the success rate of picking up large-sized chip dies using existing die picking equipment and processes. Too low a success rate of picking up can lead to abnormal situations such as more die dropping or deviation during picking up, which in turn affects the product yield of large-sized chips.

[0005] Therefore, it is necessary to propose a new die picking device and method to solve the above problems. Summary of the invention

[0006] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a die picking device and method for solving the problem that large-size chips cannot be effectively picked up in the prior art.

[0007] To achieve the above-mentioned object and other related objects, the present invention provides a grain picking device, characterized in that it comprises:

[0008] A carrier, which comprises a horizontal surface for placing the die;

[0009] A pushing element disposed in the platform includes a push pin that can switch between an extended state and a retracted state in a direction perpendicular to the horizontal platform surface; when the push pin is in an extended state, the top of the push pin is higher than the horizontal platform surface and can be kept fixed at multiple height positions;

[0010] A vacuum clamp for clamping the crystal grain from the carrier is arranged above the carrier.

[0011] As an optional solution of the present invention, the height of the top of the ejector pin above the horizontal surface can be kept fixed at least at a first height and a second height; the second height is greater than the first height, and the difference between the first height and the second height is less than the first height.

[0012] As an optional solution of the present invention, the pushing element further includes a transmission unit for driving the ejector pin to extend and retract in a direction perpendicular to the horizontal platform surface.

[0013] As an optional solution of the present invention, the pushing element further includes a timing unit for controlling the duration that the ejector pin remains fixed at the first height and the second height.

[0014] As an optional solution of the present invention, the size of the grain is greater than 25×25 mm 2 The upper surface of the pushing element is exposed to the horizontal table surface of the carrier, and the upper surface of the pushing element is a circular table with a diameter greater than 45 mm.

[0015] As an optional solution of the present invention, there are multiple ejector pins, which are arranged in a centrally symmetrical array on the circular table surface, and the distance between the outermost ejector pins in the array and the edge of the circular table surface is one third of the radius of the circular table surface.

[0016] As an optional solution of the present invention, there are five ejector pins, one of which is located at the center of the circular table, and the remaining four ejector pins are at the same distance from the ejector pin located at the center of the circular table.

[0017] As an optional solution of the present invention, the vacuum clamp includes a vacuum nozzle and a fixing structure located around the vacuum nozzle; the size of the fixing structure is greater than 20×20 mm 2 .

[0018] As an optional solution of the present invention, the grain picking device further includes:

[0019] A control unit is connected to the pushing element and the vacuum clamp, and is used to control the pushing element to push the grain, control the vacuum clamp to pick up the grain, and determine whether the vacuum clamp picks up the grain.

[0020] The present invention also provides a grain picking method, which is characterized by comprising the following steps:

[0021] 1) Providing a die picking device according to the present invention;

[0022] 2) placing the crystal grains to be picked up on the carrier;

[0023] 3) pushing the crystal grain to a first height by the ejector pin and keeping the crystal grain there for a first dwelling time;

[0024] 4) pushing the crystal grain to a second height by the ejector pin and keeping the crystal grain there for a second dwelling time, wherein the second height is greater than the first height;

[0025] 5) Picking up the die by the vacuum fixture.

[0026] As an optional solution of the present invention, the first residence time and the second residence time are 0.05 to 1 s.

[0027] As an optional solution of the present invention, the following steps are also included after step 5):

[0028] 6) Determining whether the vacuum clamp picks up the grain;

[0029] 7) When it is determined that the vacuum clamp has picked up the grain, the grain is clamped and transferred by the vacuum clamp; when it is determined that the vacuum clamp has not picked up the grain, the ejector pin is retracted to a retracted state and steps 3) to 7) are re-executed.

[0030] As described above, the present invention provides a grain picking device and method, which ensures that the grain picking process of large-size chips has a high success rate by optimizing and adjusting the grain picking device and process for large-size chips; adopts a multi-stage lifting pin design, and ensures that the vacuum clamp can successfully pick up large-size chip grains by adjusting the lifting height and dwelling time of the pin. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Shown is a partial schematic diagram of a die pickup device provided in the first embodiment of the present invention.

[0032] Figure 2 Shown is a front view schematic diagram of the pushing element provided in the first embodiment of the present invention.

[0033] Figure 3 Shown is a schematic top view of the pushing element provided in the first embodiment of the present invention.

[0034] Figure 4 Shown is a front view schematic diagram of the vacuum clamp provided in the first embodiment of the present invention.

[0035] Figure 5 Shown is a bottom view schematic diagram of the vacuum clamp provided in the first embodiment of the present invention.

[0036] Figure 6 Shown is a flow chart of a die picking method provided in the second embodiment of the present invention.

[0037] Figure 7 It is a schematic diagram showing the placement of the crystal grain to be picked up on the stage provided in the second embodiment of the present invention.

[0038] Figure 8 It is a schematic diagram showing the method of pushing a die to a first height by a push pin provided in the second embodiment of the present invention.

[0039] Fig. 9 It is a schematic diagram showing the method of pushing a die to a second height by a push pin provided in the second embodiment of the present invention.

[0040] Fig.10 It is a schematic diagram showing the picking up of a die by a vacuum clamp provided in the second embodiment of the present invention.

[0041] Fig.11 It is a schematic diagram showing the movement of a die picked up by a vacuum clamp provided in the second embodiment of the present invention.

[0042] Component number description

[0043] 101 Carrier

[0044] 101a Horizontal surface

[0045] 102 Push element

[0046] 102a Ejector pin

[0047] 102b Rod-like structure

[0048] 103 Vacuum fixture

[0049] 103a Vacuum nozzle

[0050] 103b Fixed structure

[0051] 200 grains

[0052] S1~S5 Steps 1)~5) DETAILED DESCRIPTION

[0053] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0054] See also Figures 1 to 11It should be noted that the illustrations provided in this embodiment are only schematic illustrations of the basic concept of the present invention. Although the illustrations only show components related to the present invention and are not drawn according to the number, shape and size of components in actual implementation, the form, quantity and proportion of each component in actual implementation may be changed arbitrarily, and the component layout may also be more complicated.

[0055] Embodiment 1

[0056] See also Figures 1 to 5 as well as Figures 7 to 9 This embodiment provides a die picking device, characterized by comprising:

[0057] The carrier 101 comprises a horizontal surface 101a for placing the die 200;

[0058] The pushing element 102 disposed in the carrier 101 includes a push pin 102a that can switch between an extended state and a retracted state in a direction perpendicular to the horizontal platform surface 101a; when the push pin 102a is in an extended state, the top of the push pin 102a is higher than the horizontal platform surface 101a and can be kept fixed at multiple height positions;

[0059] A vacuum clamp 103 for clamping the die 200 from the carrier 101 is disposed above the carrier 101 .

[0060] like Figure 1 , which is a partial front view schematic diagram of a grain picking device provided in this embodiment. The grain picking device includes a carrier 101. Figure 1 2 shows a partial structure of the carrier 101 for contacting the die 200, and the upper surface thereof is the horizontal surface 101a. Figure 1 Also shown is a pushing element 102 disposed in the carrier 101 and a vacuum clamp 103 disposed above the carrier 101 .

[0061] like Figure 2 FIG. 1 is a schematic front view of the pushing element 102. Figure 3 This is its top view. Figure 3 It can be seen that there are multiple ejector pins 102a, which are arranged in a centrally symmetrical array on the circular table surface, and the distance between the outermost ejector pins 102a in the array and the edge of the circular table surface is one third of the radius of the circular table surface. Specifically, there are five ejector pins 102a, one of which is located at the center of the circular table surface, and the remaining four ejector pins 102a have the same distance as the ejector pin 102a located at the center of the circular table surface. It should be noted that the arrangement of the ejector pins 102a is not limited to Figure 3 The arrangement shown can also be used to adjust the number and arrangement of the ejector pins 102 a according to the size of the die 200 .

[0062] As an example, the size of the die 200 is greater than 25×25 mm. 2 The upper surface of the pushing element 102 is exposed to the horizontal table surface 101a of the carrier 101, and the upper surface of the pushing element 102 is a circular table surface with a diameter greater than 45mm. For large-sized chip grains, their size is generally greater than 25×25mm. 2 , for example 30×26mm 2 , compared to the general size of existing conventional grains, such as 12×8mm 2 , it will be difficult to place the large-sized chip grains stably on the conventional grain carrier. By setting a circular table with a diameter greater than 45 mm, the large-sized chip grains can be stably placed on the circular table, making the grain picking process more stable. Optionally, the grain 200 can be a flip-chip grain prepared by wafer-level packaging with metal pads and solder balls formed on the surface.

[0063] like Figure 4 , which is a schematic diagram of the vacuum clamp 103, Figure 5 This is its top view.

[0064] As an example, Figure 5 As shown, the vacuum fixture 103 includes a vacuum nozzle 103a and a fixing structure 103b located around the vacuum nozzle 103a; the size of the fixing structure 103b is greater than 20×20 mm 2 .from Figure 4 and Figure 5 As can be seen in FIG. 1 , the vacuum fixture 103 is further provided with a vacuum pipe 103b, which is connected to a vacuum pump to provide vacuum negative pressure to the vacuum suction nozzle 103a. Figure 5 As shown, the vacuum fixture 103 is located at the center of the fixed structure 103b. When picking up the die 200, the vacuum nozzle 103a contacts the die 200 through the fixed structure 103b and fixes the die 200 by vacuum adsorption. It should be noted that there may be multiple vacuum nozzles 103a, and the multiple vacuum nozzles 103a may be arranged in an array evenly on the fixed structure 103b to firmly adsorb the die 200.

[0065] like Figure 7 As shown, Figure 1 Schematic diagram of the die 200 being placed on the stage 101 when the ejector pin 102a is switched to the retracted state. Figure 8 and Fig. 9As shown, when the ejector pin 102a is in the extended state, the height of the top of the ejector pin 102a above the horizontal surface 101a can be kept fixed at least at a first height H1 and a second height H2; the second height H2 is greater than the first height H1, and the difference between the first height H1 and the second height H2 is less than the first height H1. Figure 8 In the embodiment, the top of the ejector pin 102a is at a first height H1; Fig. 9 In the embodiment, the top of the ejector pin 102a is at a second height H2.

[0066] As an example, the pushing element 102 also includes a transmission unit for driving the ejector pin 102a to extend and retract in a direction perpendicular to the horizontal surface 101a. Optionally, the pushing element 102 has a rod-shaped structure 102b, which is used to fix and support the pushing element 102 and connect the ejector pin 102a and the transmission unit, so that the transmission unit can drive the ejector pin 102a to extend and retract. At the first height H1 and the second height H2, the ejector pin 102a can remain fixed, so that the grain 200 supported by the ejector pin 102a can be temporarily maintained at the corresponding fixed position. Optionally, the transmission unit includes a stepping motor, which is connected to the ejector pin 102a through the rod-shaped structure 102b to drive the ejector pin 102a to extend and retract.

[0067] As an example, the pushing element 102 further includes a timing unit for controlling the duration of the ejector pin 102a being fixed at the first height and the second height. Optionally, the timing unit is connected to the transmission unit to control the transmission unit to drive the ejector pin 102a to be fixed at the first height H1 and the second height H2. The duration can range from 0.05 to 1s, for example, 0.1s.

[0068] As an example, the die picking device further includes:

[0069] The control unit is connected to the pushing element 102 and the vacuum clamp 103 , and is used to control the pushing element 102 to push the die 200 , control the vacuum clamp 103 to pick up the die 200 , and determine whether the vacuum clamp 103 has picked up the die 200 .

[0070] Optionally, the control unit is connected to the transmission unit and the timing unit, and is used to control the transmission unit and the timing unit to drive the ejector pin 102a to extend and retract, and to maintain a fixed duration at the first height and the second height; the control unit is also connected to the vacuum clamp 103, controls the vacuum clamp 103 to pick up the die 200, and determines whether the vacuum clamp 103 picks up the die 200. For example, by measuring the vacuum state inside the vacuum clamp 103, it is determined whether the vacuum clamp 103 picks up the die 200.

[0071] As an example, the die picking process in this embodiment is after the die cutting of the wafer, and a plurality of the cut die are placed on a carrier tape not shown in the figure, and are placed on the horizontal platform 101a through the carrier tape. Through the horizontal movement of the carrier tape, the die to be picked up is sequentially transferred to the top of the pushing element 102 along the extension direction of the carrier tape, and the die is lifted up by the pushing element 102 and picked up by the vacuum clamp 103. The vacuum clamp 103 picks up the die and transfers it to the next packaging processing station.

[0072] Embodiment 2

[0073] like Figures 6 to 11 As shown, this embodiment provides a method for picking up a die, characterized in that it includes the following steps:

[0074] 1) Providing a die picking device as described in Embodiment 1;

[0075] 2) placing the die 200 to be picked up on the carrier 101;

[0076] 3) Pushing the crystal grain 200 to a first height and keeping it there for a first dwelling time by the ejector pin 102a;

[0077] 4) Pushing the die 200 to a second height and keeping it there for a second dwelling time by the ejector pin 102a, wherein the second height is greater than the first height;

[0078] 5) Pick up the die 200 by the vacuum clamp 103 .

[0079] In step 1), refer to Figure 6 The S1 step and Figures 1 to 5 , providing a die picking device as described in the first embodiment. Figures 1 to 5 As shown, the grain picking method of this embodiment is based on the grain picking device described in Embodiment 1. In other implementation cases of the present invention, the grain picking method can also be based on a grain picking device with a similar structure to the grain picking device described in Embodiment 1, which does not affect the implementation of the grain picking method provided by the present invention.

[0080] In step 2), refer to Figure 6 The S2 step and Figure 7 , placing the crystal grain 200 to be picked up on the carrier 101. Figure 7 As shown, when the die 200 is placed on the carrier 101, the ejector pins 102a are in a retracted state, and the lower surface of the die 200 is flush with the surface of the horizontal platform 101a. This ensures that the die 200 is placed on the carrier 101 in a stable posture.

[0081] In step 3), refer to Figure 6 The S3 steps and Figure 8 , the die 200 is pushed to a first height H1 by the ejector pin 102a and stays there for a first dwelling time. Figure 8 As shown, the driving unit controls the ejector pin 102a to push the die 200 to a first height H1. Optionally, the die 200 is kept at the first height H1 for a first dwell time, which is 0.05-1s, for example, 0.1s.

[0082] In step 4), refer to Figure 6 The S4 step and Fig. 9 , the die 200 is pushed to a second height H2 by the ejector pin 102a and stays there for a second dwelling time, wherein the second height H2 is greater than the first height H1. Fig. 9 As shown, the driving unit controls the ejector pin 102a to continue to push the grain 200 to a second height H2. Optionally, it maintains a second dwell time at the second height H2, and the second dwell time is 0.05 to 1s, for example, 0.1s. In other embodiments of the present invention, the second dwell time and the first dwell time can also be set to be different.

[0083] In step 5), refer to Figure 6 S5 steps and Figures 10 to 11 , the die 200 is picked up by the vacuum clamp 103. Fig.10 In the figure, the vacuum clamp 103 approaches the die 200 along the direction of the arrow in the figure to pick up the die. After the vacuum clamp 103 adsorbs and fixes the die 200, the vacuum clamp 103 picks up the die 200 to the next packaging process station for further processing.

[0084] As an example, after step 5), the following steps are also included:

[0085] 6) Determine whether the vacuum clamp 103 picks up the die 200;

[0086] 7) When it is determined that the vacuum clamp 103 picks up the die 200, the die 200 is clamped and transferred by the vacuum clamp 103; when it is determined that the vacuum clamp 103 does not pick up the die 200, the ejector pin 102a is retracted to the retracted state and steps 3) to 7) are re-executed.

[0087] The grains of large-size chips have large size and mass, and the picking process is difficult. If the vacuum clamp 103 moves the grain 200 before it firmly adsorbs the grain 200, it may cause the grain to fall or even break. Before the grain moves, first determine whether the vacuum clamp 103 picks up the grain 200 to avoid the above situation. It is necessary to determine whether the vacuum clamp 103 picks up the grain 200 through a control unit. For example, by measuring the vacuum state inside the vacuum clamp 103, it is determined whether the vacuum clamp 103 picks up the grain 200. If it is found that the grain 200 is not picked up, steps 3) to 7) can be repeatedly performed until the vacuum clamp 103 picks up the grain 200.

[0088] In summary, the present invention provides a device and method for picking up grains, the device comprising: a carrier, comprising a horizontal surface for placing grains; a pushing element disposed in the carrier, comprising a pin that can switch between extended and retracted states in a direction perpendicular to the horizontal surface; when the pin is in an extended state, the top of the pin is higher than the horizontal surface and can remain fixed at multiple height positions; a vacuum clamp for clamping the grains from the carrier, which is disposed above the carrier. The present invention optimizes and adjusts the device and process for picking up grains of large-size chips, thereby ensuring that the process for picking up grains of large-size chips has a high success rate; a multi-stage lifting pin design is adopted, and by adjusting the lifting height and dwell time of the pin, it is ensured that the vacuum clamp can successfully pick up large-size chip grains.

[0089] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A grain picking device, characterized in that: include: A carrier, which comprises a horizontal surface for placing the die; The ejection element disposed in the carrier comprises an ejector pin which can switch between an extended state and a retracted state in a direction perpendicular to the horizontal platform surface, and the ejector pin is used to push and support the grain; when the ejector pin is in an extended state, the ejector pin supports the grain, and the height of the top of the ejector pin above the horizontal platform surface can be kept fixed at least at a first height and a second height; the second height is greater than the first height, and the difference between the first height and the second height is less than the first height; wherein the size of the grain is greater than 25×25 mm 2 , the upper surface of the pushing element is exposed to the horizontal table surface of the carrier, and the upper surface of the pushing element is a circular table with a diameter greater than 45 mm; there are multiple ejector pins, and the multiple ejector pins are arranged in a centrally symmetrical array on the circular table, and the distance between the outermost ejector pins in the array and the edge of the circular table is one third of the radius of the circular table; A vacuum clamp for clamping the crystal grain from the carrier is arranged above the carrier.

2. The die pick-up device according to claim 1, characterized in that: The pushing element also includes a transmission unit for driving the ejector pin to extend and retract in a direction perpendicular to the horizontal platform surface.

3. The die pick-up device according to claim 1, characterized in that: The ejection element further includes a timing unit for controlling the duration of time that the ejector pin remains fixed at the first height and the second height.

4. The die pick-up device according to claim 1, characterized in that: There are five ejector pins, one of which is located at the center of the circular table, and the remaining four ejector pins are at the same distance from the ejector pin located at the center of the circular table.

5. The die pick-up device according to claim 1, characterized in that: The vacuum fixture comprises a vacuum nozzle and a fixing structure located around the vacuum nozzle; the size of the fixing structure is greater than 20×20 mm 2 .

6. The die pick-up device according to claim 1, characterized in that: Also includes: A control unit is connected to the pushing element and the vacuum clamp, and is used to control the pushing element to push the grain, control the vacuum clamp to pick up the grain, and determine whether the vacuum clamp picks up the grain.

7. A grain picking method, characterized in that: The following steps are involved: 1) Providing a die pickup device as claimed in any one of claims 1 to 6; 2) placing the crystal grains to be picked up on the carrier; 3) pushing the crystal grain to a first height by the ejector pin and keeping the crystal grain there for a first dwelling time; 4) pushing the crystal grain to a second height by the ejector pin and keeping the crystal grain there for a second dwelling time, wherein the second height is greater than the first height; 5) Picking up the die by the vacuum clamp.

8. The method for preparing a grain picking device according to claim 7, characterized in that: The first residence time and the second residence time are 0.05 to 1 s.

9. The method for preparing a grain picking device according to claim 7, characterized in that: After step 5), the following steps are also included: 6) Determining whether the vacuum clamp picks up the grain; 7) When it is determined that the vacuum clamp has picked up the grain, the grain is clamped and transferred by the vacuum clamp; when it is determined that the vacuum clamp has not picked up the grain, the ejector pin is retracted to a retracted state and steps 3) to 7) are re-executed.

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