Wafer level package mold preventing separation film from floating up

Abstract

The utility model discloses a wafer level packaging mould of preventing separation membrane from floating, including upper die and lower die, the lower die includes main cavity board and the base of being located main cavity board below, the separation membrane is located the top surface of main cavity board, the inside of main cavity board is provided with first adsorption loop, the inside of base is provided with second adsorption loop, first adsorption loop is linked together with second adsorption loop for adsorbing separation membrane, first adsorption loop penetrates the thickness direction of main cavity board, the center of main cavity board is located the area of first adsorption loop within. The utility model discloses a wafer level packaging mould of preventing separation membrane from floating, through setting up the first adsorption loop of covering the middle part of main cavity board in the main cavity board of lower die, and it is linked together with the second adsorption loop of base, is favorable to increase the adhesion of separation membrane in lower die, makes separation membrane not to be absorbed upward because of negative pressure, thereby avoids the product quality problem.

Description

Technical Field

[0001] This utility model belongs to the field of semiconductor injection molding technology, specifically relating to a wafer-level packaging mold that prevents the separation membrane from floating. Background Technology

[0002] In existing technologies, when a vacuum is opened inside the mold during semiconductor wafer-level packaging, the negative pressure inside the mold will suck up the separation film in the lower mold, causing the resin on the separation film to come into premature contact with the wafer and chip in the upper mold, resulting in product quality problems. Utility Model Content

[0003] In view of this, in order to overcome the shortcomings of the prior art, the purpose of this utility model is to provide a wafer-level packaging mold that prevents the separation membrane from floating.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A wafer-level packaging mold for preventing the separation membrane from floating includes an upper mold and a lower mold. The lower mold includes a main cavity plate and a base located below the main cavity plate. The separation membrane is located on the top surface of the main cavity plate. A first adsorption circuit is provided inside the main cavity plate, and a second adsorption circuit is provided inside the base. The first adsorption circuit and the second adsorption circuit are connected to adsorb the separation membrane. The first adsorption circuit extends through the thickness direction of the main cavity plate, and the center of the main cavity plate is located within the region of the first adsorption circuit.

[0005] By setting a first adsorption circuit in the main cavity plate of the lower mold, the first adsorption circuit covers the middle part of the main cavity plate and is connected to the second adsorption circuit of the base. The setting of the first adsorption circuit helps to increase the adhesion of the separation membrane to the lower mold, so that the separation membrane will not be sucked up due to negative pressure, thereby avoiding product quality problems.

[0006] According to some preferred embodiments of this utility model, the main cavity plate has multiple adsorption holes vertically downwards from its top surface. Each adsorption hole contains a fixing pin, the length of which is greater than the depth of the adsorption hole, and the depth of the adsorption hole is less than the thickness of the main cavity plate. The fixing pins are provided to facilitate control of the airflow channel size in the first adsorption circuit, thereby controlling the airflow magnitude.

[0007] According to some preferred embodiments of the present invention, each of the adsorption holes includes a first hole portion and a second hole portion that are connected to each other, the axis of the first hole portion coincides with the axis of the second hole portion, the first hole portion is located above the second hole portion and the diameter of the first hole portion is smaller than the diameter of the second hole portion.

[0008] According to some preferred embodiments of the present invention, each fixing pin includes a head, a main body and a bottom from top to bottom. The centerline of the bottom coincides with the centerline of the main body. The top surface of the head is flush with the top surface of the first hole. The bottom surface of the bottom is in contact with the top surface of the base. The bottom is located below the second hole.

[0009] According to some preferred embodiments of the present invention, the length of the head is greater than the depth of the first hole, the outer diameter of the main body is equal to the outer diameter of the head and less than the diameter of the second hole, the length of the bottom is greater than the diameter of the second hole, and the width of the bottom is less than the diameter of the second hole.

[0010] According to some preferred embodiments of this utility model, the outer peripheral surface of the head includes multiple cut surfaces and multiple arc-shaped surfaces. The length of each cut surface and arc-shaped surface is equal to the length of the head. Each cut surface is a plane, and the multiple cut surfaces are evenly spaced around the axis of the head. Each arc-shaped surface connects two adjacent cut surfaces. The arc-shaped surface fits against the inner wall of the first hole, and there is a gap between the cut surface and the inner wall of the first hole. The cut surfaces of the outer peripheral surface of the fixing needle head are formed by cutting. The design of the cut surfaces ensures that there is a gap between part of the outer wall of the head and the first hole, and the cut surfaces extend into the second hole. This ensures communication between the first hole and the second hole after the fixing needle is installed, ensuring air venting. In addition, in some embodiments of this utility model, the depth and number of cut surfaces can be set according to the adsorption effect. The deeper and more numerous the cut surfaces, the better the adsorption effect, but the larger the trace left on the surface of the encapsulated body.

[0011] According to some preferred embodiments of the present invention, the main cavity plate has multiple sets of adsorption units, each set of adsorption units includes multiple adsorption holes evenly spaced apart and a fixing pin disposed in each adsorption hole, the multiple adsorption holes of each set of adsorption units enclose a circular area, and the multiple sets of adsorption units are arranged sequentially and spaced apart from the center of the main cavity plate.

[0012] According to some preferred embodiments of the present invention, the main cavity plate has a plurality of first grooves vertically upward from its bottom surface. The plurality of first grooves are arranged one-to-one with a plurality of adsorption units, and each first groove is connected to a plurality of adsorption holes of a corresponding adsorption unit. The sum of the depths of the adsorption holes and the first grooves is equal to the thickness of the main cavity plate. The bottoms of the plurality of fixing pins in each adsorption unit are located in the corresponding first groove.

[0013] According to some preferred embodiments of the present invention, the main cavity plate is further provided with two intersecting and perpendicular second grooves on its bottom surface. The second grooves pass through the axis of the main cavity plate, and the depth of the second grooves is equal to the depth of the first grooves. Each second groove is used to connect all the first grooves. The plurality of adsorption units together with the plurality of first grooves and the two second grooves form the first adsorption circuit.

[0014] According to some preferred embodiments of this utility model, the base has multiple through holes extending through its thickness direction, and these through holes are connected to the second groove. The base has two intersecting and perpendicular third grooves extending upwards from its bottom surface. These third grooves pass through the axis of the main cavity plate and are also connected to the through holes, with each through hole located at one end of a third groove. The length of the third groove is less than the length of the second groove, and the orthographic projection of the third groove onto the bottom surface of the main cavity plate coincides with the second groove. The multiple through holes and the two third grooves together form the second adsorption circuit. The two third grooves are provided to connect the multiple through holes, thereby converging the exhaust gases from the first and second adsorption circuits to the center of the base's bottom surface, where they can then cooperate with the exhaust ports on the molding press.

[0015] By adopting the above technical solution, compared with the prior art, the wafer-level packaging mold of this utility model for preventing the separation membrane from floating up, by setting a first adsorption circuit covering the middle of the main cavity plate in the lower mold and connecting it to the second adsorption circuit of the base, helps to increase the adhesion of the separation membrane on the lower mold, so that the separation membrane will not be sucked up due to negative pressure, thereby avoiding product quality problems. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a three-dimensional structural diagram of the wafer-level packaging mold in a preferred embodiment of the present invention; Figure 2 This is a three-dimensional structural diagram of the lower mold in a preferred embodiment of the present invention; Figure 3 This is a cross-sectional view of the lower mold in a preferred embodiment of the present invention; Figure 4 This is a bottom view of the main cavity plate in a preferred embodiment of the present invention; Figure 5This is a three-dimensional structural diagram of the fixing pin in a preferred embodiment of the present invention; Figure 6 This is a top view of the fixing pin in a preferred embodiment of the present invention; The attached figures are labeled as follows: Upper mold-10, lower mold-20, main cavity plate-1, adsorption unit-11, first hole-111, second hole-112, head-113, cut surface-1131, arc surface-1132, main body-114, bottom-115, first groove-12, second groove-13, base-2, through hole-21, third groove-22, first movable cavity plate-3, second movable cavity plate-4. Detailed Implementation

[0018] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0019] Reference Figures 1 to 6 This embodiment provides a wafer-level packaging mold for preventing the separation membrane from floating, comprising an upper mold 10 and a lower mold 20 that cooperate with each other. The lower mold 20 includes a main cavity plate 1, a base 2 located below the main cavity plate 1, and a first movable cavity plate 3 and a second movable cavity plate 4 surrounding the outer periphery of the main cavity plate 1. The separation membrane is located on the top surface of the main cavity plate 1, and the area of ​​the separation membrane is larger than the area of ​​the main cavity plate 1. In this embodiment, a first adsorption circuit is provided inside the main cavity plate 1, and a second adsorption circuit is provided inside the base 2. The first adsorption circuit penetrates the thickness direction of the main cavity plate 1, and the second adsorption circuit penetrates the thickness direction of the base 2. The first adsorption circuit and the second adsorption circuit are connected to adsorb the separation membrane.

[0020] Furthermore, the main cavity plate 1 has multiple sets of adsorption units 11. Each set of adsorption units 11 includes multiple adsorption holes evenly spaced apart and a fixing pin disposed in each adsorption hole. The multiple adsorption holes of each set of adsorption units 11 enclose a circular area. The multiple sets of adsorption units 11 are arranged sequentially and spaced apart from the center of the main cavity plate 1, that is, the multiple sets of adsorption units 11 are arranged in a concentric circle. In this embodiment, an adsorption hole is provided at the center of the main cavity plate 1 and a fixing pin is installed in the adsorption hole.

[0021] Specifically, the adsorption hole is vertically downwardly opened from the top surface of the main cavity plate 1. The depth of the adsorption hole is less than the thickness of the main cavity plate 1, and the length of the fixing pin is greater than the depth of the adsorption hole. For example, Figure 3 and Figure 4 As shown, each adsorption pore includes a first pore portion 111 and a second pore portion 112 that are connected to each other. The axis of the first pore portion 111 coincides with the axis of the second pore portion 112. The first pore portion 111 is located above the second pore portion 112 and the diameter of the first pore portion 111 is smaller than the diameter of the second pore portion 112.

[0022] like Figure 3 , Figure 5 and Figure 6 As shown, each fixing pin includes a head 113, a main body 114 and a bottom 115 from top to bottom. The axis of the bottom 115 coincides with the axis of the main body 114. The outer diameter of the main body 114 is equal to the outer diameter of the head 113. The top surface of the head 113 is flush with the top surface of the first hole 111. The bottom surface of the bottom 115 is in contact with the top surface of the base 2. The outer peripheral surface of the head 113 includes multiple cut surfaces 1131 and multiple arc surfaces 1132. The length of each cut surface 1131 and arc surface 1132 is equal to the length of the head 113. Each cut surface 1131 is a plane. The multiple cut surfaces 1131 are evenly spaced around the axis of the head 113. Each arc surface 1132 is connected between two adjacent cut surfaces 1131. The arc surface 1132 fits against the inner wall of the first hole 111. There is a gap between the cut surface 1131 and the inner wall of the first hole 111. The length of the head 113 is greater than the depth of the first hole 111, ensuring that the connection between the first hole 111 and the second hole 112 is maintained after the fixing pin is installed, without affecting the exhaust. Furthermore, the bottom 115 is located below the second hole 112, the outer diameter of the main body 114 is smaller than the diameter of the second hole 112, the length of the bottom 115 is greater than the diameter of the second hole 112, and the width of the bottom 115 is smaller than the diameter of the second hole 112, so as to ensure that the second hole 112 can limit the bottom 115 of the fixing pin, thereby fixing the fixing pin.

[0023] like Figure 3 and Figure 4As shown, the main cavity plate 1 has multiple first grooves 12 vertically upward from its bottom surface. Each first groove 12 corresponds to one of the multiple adsorption units 11, and each first groove 12 communicates with multiple adsorption holes of a corresponding adsorption unit 11. The sum of the depths of the adsorption holes and the first grooves 12 is equal to the thickness of the main cavity plate 1. The bottoms 115 of the multiple fixing pins in each adsorption unit 11 are located in the corresponding first groove 12. The main cavity plate 1 also has two intersecting and perpendicular second grooves 13 vertically upward from its bottom surface. The second grooves 13 pass through the axis of the main cavity plate 1, and their depth is equal to the depth of the first grooves 12. Each second groove 13 connects all the first grooves 12. In this embodiment, the multiple adsorption units 11, the multiple first grooves 12, and the two second grooves 13 together form a first adsorption circuit, and the center of the main cavity plate 1 is located within the area of ​​the first adsorption circuit, ensuring that the first adsorption circuit can adsorb most of the middle portion of the separation membrane above the main cavity plate 1.

[0024] Furthermore, such as Figure 3 As shown, the base 2 has multiple through holes 21 extending through its thickness, which are connected to the second groove 13. The base 2 also has two intersecting and perpendicular third grooves 22 extending upwards from its bottom surface. These third grooves 22 pass through the axis of the main cavity plate 1 and are also connected to the through holes 21. Each through hole 21 is located at one end of a third groove 22. The length of the third groove 22 is less than the length of the second groove 13, and the orthographic projection of the third groove 22 onto the bottom surface of the main cavity plate 1 coincides with the second groove 13. The multiple through holes 21 and the two third grooves 22 together form a second adsorption circuit. The two third grooves 22 are designed to connect the multiple through holes 21, allowing the air from the first and second adsorption circuits to be collected at the center of the bottom surface of the base 2, thus cooperating with the air outlet on the molding press.

[0025] The above embodiments are only for illustrating the technical concept and features of this utility model. Their purpose is to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They should not be used to limit the protection scope of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be included within the protection scope of this utility model.

Claims

1. A wafer-level packaging mold for preventing the separation membrane from floating, comprising an upper mold and a lower mold, the lower mold comprising a main cavity plate and a base located below the main cavity plate, the separation membrane being located on the top surface of the main cavity plate, characterized in that, The main cavity plate is provided with a first adsorption circuit inside, and the base is provided with a second adsorption circuit inside. The first adsorption circuit and the second adsorption circuit are connected to each other for adsorbing the separation membrane. The first adsorption circuit runs through the thickness direction of the main cavity plate, and the center of the main cavity plate is located in the area of ​​the first adsorption circuit.

2. The wafer-level packaging mold according to claim 1, characterized in that, The main cavity plate has multiple adsorption holes vertically downward from its top surface. Each adsorption hole is equipped with a fixing pin. The length of the fixing pin is greater than the depth of the adsorption hole, and the depth of the adsorption hole is less than the thickness of the main cavity plate.

3. The wafer-level packaging mold according to claim 2, characterized in that, Each of the adsorption pores includes a first pore portion and a second pore portion that are connected to each other. The axis of the first pore portion coincides with the axis of the second pore portion. The first pore portion is located above the second pore portion and the diameter of the first pore portion is smaller than the diameter of the second pore portion.

4. The wafer-level packaging mold according to claim 3, characterized in that, Each of the fixing pins comprises a head, a main body, and a bottom from top to bottom. The centerline of the bottom coincides with the centerline of the main body. The top surface of the head is flush with the top surface of the first hole. The bottom surface of the bottom is in contact with the top surface of the base. The bottom is located below the second hole.

5. The wafer-level packaging mold according to claim 4, characterized in that, The length of the head is greater than the depth of the first hole, the outer diameter of the main body is equal to the outer diameter of the head and less than the diameter of the second hole, the length of the bottom is greater than the diameter of the second hole, and the width of the bottom is less than the diameter of the second hole.

6. The wafer-level packaging mold according to claim 5, characterized in that, The outer peripheral surface of the head includes multiple cut surfaces and multiple arc surfaces. The length of each cut surface and arc surface is equal to the length of the head. Each cut surface is a plane. The multiple cut surfaces are evenly spaced around the axis of the head. Each arc surface is connected between two adjacent cut surfaces. The arc surface fits against the inner wall of the first hole. There is a gap between the cut surface and the inner wall of the first hole.

7. The wafer-level packaging mold according to claim 4, characterized in that, The main cavity plate has multiple sets of adsorption units. Each set of adsorption units includes multiple adsorption holes evenly spaced apart and a fixing pin disposed in each adsorption hole. The multiple adsorption holes of each set of adsorption units enclose a circular area. The multiple sets of adsorption units are arranged sequentially and spaced apart from the center of the main cavity plate.

8. The wafer-level packaging mold according to claim 7, characterized in that, The main cavity plate has multiple first grooves vertically upward from its bottom surface. Each of the multiple first grooves corresponds to a multiple adsorption unit, and each first groove is connected to multiple adsorption holes of a corresponding adsorption unit. The sum of the depths of the adsorption holes and the first grooves is equal to the thickness of the main cavity plate. The bottoms of the multiple fixing pins in each adsorption unit are located in the corresponding first groove.

9. The wafer-level packaging mold according to claim 8, characterized in that, The main cavity plate also has two intersecting and perpendicular second grooves vertically upward formed on its bottom surface. The second grooves pass through the axis of the main cavity plate, and the depth of the second grooves is equal to the depth of the first grooves. Each second groove is used to connect all the first grooves. The multiple adsorption units, the multiple first grooves, and the two second grooves together form the first adsorption circuit.

10. The wafer-level packaging mold according to claim 9, characterized in that, The base has multiple through holes extending through its thickness, which are connected to the second groove. The base has two intersecting and perpendicular third grooves extending upwards from its bottom surface. The third grooves pass through the axis of the main cavity plate and are also connected to the through holes. Each through hole is located at one end of the third groove. The length of the third groove is less than the length of the second groove, and the orthographic projection of the third groove on the bottom surface of the main cavity plate coincides with the second groove. The multiple through holes and the two third grooves together form the second adsorption circuit.

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