Anti-splashing chip pre-packaging cover body and chip pre-packaging method

Abstract

The invention relates to an anti-splashing chip pre-packaging cover body and a chip pre-packaging method, the anti-splashing chip pre-packaging cover body comprises an annular wall and a mold sheet layer, and the annular wall and the mold sheet layer are both made of polydimethylsiloxane; one end of the annular wall is connected to the peripheral edge of the mold sheet layer, the annular wall is perpendicular to the mold sheet layer, and a concave structure which is arranged corresponding to a pattern on a pre-packaged chip and has the same shape as the pattern on the pre-packaged chip is formed on one side surface, close to the annular wall, of the mold sheet layer; the inner side wall of the annular wall is matched with the peripheral edge of the pre-packaged chip, and the axial height of the annular wall is larger than the thickness of the pre-packaged chip, so that when the inner side wall of the other end of the annular wall is fixed to the peripheral edge of the pre-packaged chip, an avoiding gap is reserved between the inner surface of the mold sheet layer and the top of the pre-packaged chip. The surface of the surface acoustic wave filter can be isolated, so that splashes generated in the welding process are effectively isolated, the filter is protected against pollution, meanwhile, the packaging process is simplified, the cost is reduced, and the production efficiency and the product quality are improved.

Description

Technical Field

[0001] The present invention relates to the technical field related to semiconductor packaging, and in particular to a splash-proof chip pre-packaging cover and a chip pre-packaging method. Background Art

[0002] With the rapid development of wireless communication technology, surface acoustic wave filters are key components of the RF front end, and their performance is crucial to the quality of the entire communication system. Although traditional packaging methods such as wafer-level packaging (WLP) technology can reduce the impact of splashing waste on filter performance to a certain extent, this technology has the disadvantages of high equipment cost, complex process flow, and cumbersome operation, which increases production costs and manufacturing difficulty.

[0003] In the process of using energy storage welding sealing tubes, it is easy to generate excess metal splashes due to factors such as tube seat and tube cap processing errors, tooling fixture loss, and excessive welding head temperature. When the excess metal splashes fall on the functional area on the surface of the interdigital transducer, it will have a great impact on the performance of the device. Summary of the invention

[0004] In order to solve one or more technical problems existing in the prior art, the present invention provides a splash-proof chip pre-packaging cover and a chip pre-packaging method.

[0005] The technical solution of the present invention for solving the above technical problems is as follows: a splash-proof chip pre-packaging cover, comprising an annular wall and a mold layer, both of which are made of polydimethylsiloxane; one end of the annular wall is connected to the peripheral edge of the mold layer, the annular wall and the mold layer are arranged vertically, and a side surface of the mold layer close to the annular wall is formed with a recessed structure arranged corresponding to and having the same shape as a pattern on the pre-packaged chip; the inner side wall of the annular wall is adapted to the peripheral edge of the pre-packaged chip, and the axial height of the annular wall is greater than the thickness of the pre-packaged chip, so that when the inner side wall of the other end of the annular wall is fixed to the peripheral edge of the pre-packaged chip, an avoidance gap is reserved between the inner surface of the mold layer and the top of the pre-packaged chip.

[0006] The beneficial effects of the present invention are as follows: the anti-splash chip pre-packaging cover of the present invention can isolate the surface of the surface acoustic wave filter, thereby effectively isolating the spatter generated during the welding process and protecting the filter from contamination, while simplifying the packaging process, reducing costs, and improving production efficiency and product quality.

[0007] Based on the above technical solution, the present invention can also be improved as follows.

[0008] Furthermore, one end of the annular wall is integrally connected to the peripheral edge of the mold sheet layer.

[0009] Furthermore, the thickness of the ring wall is uniform.

[0010] Furthermore, the axial height of the annular wall is uniform.

[0011] A chip prepackaging method comprises the following steps:

[0012] S1, using the mold substrate to perform the same photolithography coating stripping operation as that used to prepare the pre-packaged chip, and cutting it into the same size as the pre-packaged chip to obtain a mold chip;

[0013] S2, placing the mold chip into the mold box, pouring polydimethylsiloxane so that the polydimethylsiloxane fills the periphery and top of the mold chip;

[0014] S3, after the polydimethylsiloxane is completely cured, a demoulding process is performed to achieve pattern transfer, thereby obtaining the above-mentioned anti-splash chip pre-packaged cover;

[0015] S4, sticking the other end of the ring wall of the anti-splash chip pre-packaging cover to the surrounding side walls of the chip to be packaged in the tube shell, and performing a baking process.

[0016] The beneficial effects of the present invention are as follows: the chip pre-packaging method of the present invention, by using polydimethylsiloxane for pre-packaging, effectively isolates welding spatter, reduces its adverse effect on the performance of the surface acoustic wave filter, and improves the yield and reliability of the product. Compared with the traditional high-cost packaging technology, the pre-packaging method of the present invention has simple equipment and convenient operation, which helps to reduce production costs. The simplified process reduces the production cycle and improves production efficiency. The polydimethylsiloxane PDMS material is non-toxic and harmless, easy to handle, and meets environmental protection requirements.

[0017] Furthermore, the thickness of the mold substrate is greater than the thickness of the chip substrate used to prepare the pre-packaged chip.

[0018] Furthermore, in S1, the same photolithography, coating and stripping operations as those used to prepare pre-packaged chips are performed on the mold substrate, including cleaning the mold substrate, evenly spreading photoresist on the upper surface of the mold substrate, and then performing photolithography, coating and stripping operations, and then performing wafer testing and dicing to obtain the mold chip.

[0019] Furthermore, the inner surface of the mold sheet layer does not contact the top of the chip to be packaged.

[0020] Furthermore, the other end surface of the annular wall is flush with the bottom surface of the mold substrate.

[0021] Furthermore, the upper surface and the lower surface of the mold substrate are parallel and both are planes, the upper surface and the lower surface of the chip substrate are parallel and both are planes, and the material of the mold substrate is the same as that of the chip substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a flow chart of the chip prepackaging method of the present invention;

[0023] Figure 2 Schematic diagram of the structure of the pre-packaged chip prepared by the present invention Figure 1 ;

[0024] Figure 3 Schematic diagram of the structure of the pre-packaged chip prepared by the present invention Figure 2 ;

[0025] Figure 4 Schematic diagram of the structure of the pre-packaged chip prepared by the present invention Figure 3 ;

[0026] Figure 5 Schematic diagram of the structure of the pre-packaged chip prepared by the present invention Figure 4 ;

[0027] Figure 6 Schematic diagram of the structure of the pre-packaged cover for preparing the anti-splash chip of the present invention Figure 1 ;

[0028] Figure 7 Schematic diagram of the structure of the pre-packaged cover for preparing the anti-splash chip of the present invention Figure 2 ;

[0029] Figure 8 Schematic diagram of the structure of the pre-packaged cover for preparing the anti-splash chip of the present invention Figure 3 ;

[0030] Fig. 9 Schematic diagram of the structure of the pre-packaged cover for preparing the anti-splash chip of the present invention Figure 4 ;

[0031] Fig.10 Schematic diagram of the structure of the pre-packaged cover for preparing the anti-splash chip of the present invention Figure 5 ;

[0032] Fig.11 Schematic diagram of the structure of the pre-packaged cover for preparing the anti-splash chip of the present invention Figure 6 ;

[0033] Fig.12 Schematic diagram of the structure of the pre-packaged cover for preparing the anti-splash chip of the present invention Figure 7 .

[0034] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0035] 1. Ring wall; 11. Mold layer; 2. Chip substrate; 3. Mold substrate; 4. Photoresist; 5. Metal electrode. DETAILED DESCRIPTION

[0036] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0037] like Fig.11 and Fig.12 As shown, a splash-proof chip pre-packaged cover of the present embodiment comprises an annular wall 1 and a mold sheet layer 11, both of which are made of polydimethylsiloxane (PDMS); one end of the annular wall 1 is connected to the peripheral edge of the mold sheet layer 11, the annular wall 1 and the mold sheet layer 11 are arranged vertically, and a concave structure corresponding to the pattern on the pre-packaged chip and having the same shape is formed on a side of the mold sheet layer 11 close to the annular wall; the inner side wall of the annular wall 1 is adapted to the peripheral edge of the pre-packaged chip, and the axial height of the annular wall 1 is greater than the thickness of the pre-packaged chip, so that when the inner side wall of the other end of the annular wall 1 is fixed to the peripheral edge of the pre-packaged chip, an avoidance gap is reserved between the inner surface of the mold sheet layer 11 and the top of the pre-packaged chip.

[0038] like Fig.11 and Fig.12 As shown, a preferred solution of this embodiment is that one end of the annular wall 1 is integrally connected to the peripheral edge of the mold sheet layer 11 .

[0039] Preferably, Figure 10 to Figure 12 As shown, the thickness of the annular wall 1 of this embodiment is uniform and consistent. The axial height of the annular wall 1 is uniform and consistent, thereby ensuring the stability of the overall structural strength of the entire pre-packaged cover when in use.

[0040] The anti-splash chip pre-packaging cover of this embodiment can isolate the surface of the surface acoustic wave filter, thereby effectively isolating the spatter generated during the welding process and protecting the filter from contamination, while simplifying the packaging process, reducing costs, and improving production efficiency and product quality.

[0041] This embodiment also provides a chip pre-packaging method, such as Figures 1 to 12 As shown, the following steps are included:

[0042] S1, using the mold substrate 3 to perform the same photolithography coating stripping operation as that used to prepare the pre-packaged chip, and cutting it into the same size as the pre-packaged chip to obtain a mold chip;

[0043] S2, placing the mold chip into the mold box, pouring polydimethylsiloxane so that the polydimethylsiloxane fills the periphery and top of the mold chip;

[0044] S3, after the polydimethylsiloxane is completely cured, a demoulding process is performed to achieve pattern transfer, thereby obtaining the above-mentioned anti-splash chip pre-packaged cover;

[0045] S4, the other end of the ring wall of the anti-splash chip pre-packaging cover is pasted on the surrounding side walls of the chip to be packaged in the tube shell, and the process is baked. After the PDMS pre-packaging is completed, the subsequent operation is carried out according to the conventional energy storage welding packaging process. Due to the presence of the PDMS pre-packaging layer, the influence of spatter on the filter during the welding process can be effectively reduced.

[0046] In this embodiment, Figure 2 to Figure 5 They are photoresist, photolithography, coating and stripping operations, and their purpose is to prepare chip samples to be packaged. Figure 6 to Figure 9 They are photoresist, photolithography, coating and stripping operations, and their purpose is to prepare mold chips. Fig.10 The purpose of the PDMS pouring operation is to transfer the pattern of the mold chip to the PDMS, and then perform demolding to form Fig.11 The pre-packaged cover body in. Fig.12 For PDMS pre-packaging, Figure 5 The chip sample to be packaged is subjected to PDMS pre-packaging operation to achieve the purpose of splash prevention.

[0047] like Figure 5 and Fig. 9 As shown, the thickness of the mold substrate 3 of this embodiment is greater than the thickness of the chip substrate 2 used to prepare the pre-packaged chip.

[0048] Specifically, in S1, the same photolithography coating stripping operation as that used to prepare the pre-packaged chip is performed using the mold substrate 3, including cleaning the mold substrate 3, then evenly laying the photoresist 4 on the upper surface of the mold substrate 3, and then performing photolithography, coating and stripping operations, and then dicing after wafer testing to obtain a mold chip with a metal electrode 5. The same photolithography coating stripping operation is used for pattern transfer. If the pre-packaged cover is used to package the pre-packaged chip, if the cover collapses due to changes in air pressure, temperature, etc., it can prevent polydimethylsiloxane from directly contacting the metal electrode 5 of the pre-packaged chip to prevent affecting the device performance.

[0049] like Fig.12 As shown, the inner surface of the mold sheet layer 11 does not contact the top of the chip to be packaged.

[0050] like Fig.12 As shown, the other end surface of the annular wall 1 of this embodiment is flush with the bottom surface of the mold substrate 3 .

[0051] like Fig.11 and Fig.12As shown, in this embodiment, the upper surface and lower surface of the mold substrate 3 are parallel and both are planes, the upper surface and lower surface of the chip substrate 2 are parallel and both are planes, and the material of the mold substrate 3 is the same as that of the chip substrate 2.

[0052] In this embodiment, polydimethylsiloxane is selected as the pre-packaging material because of its excellent flexibility, high temperature resistance and good chemical stability. A PDMS film layer suitable for pre-packaging of surface acoustic wave filters is prepared through a specific ratio and mixing process (general ratio, the mass ratio of PDMS glue and curing agent is 10:1).

[0053] The chip pre-packaging method of this embodiment uses polydimethylsiloxane for pre-packaging, which effectively isolates welding spatter, reduces its adverse effects on the performance of the surface acoustic wave filter, and improves the yield and reliability of the product. Compared with the traditional high-cost packaging technology, the pre-packaging method of the present invention has simple equipment and convenient operation, which helps to reduce production costs. The simplified process reduces the production cycle and improves production efficiency. Polydimethylsiloxane PDMS material is non-toxic and harmless, easy to handle, and meets environmental protection requirements.

[0054] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0055] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0056] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0058] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0059] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A splash-proof chip pre-package cover, characterized in that: The invention comprises an annular wall and a mold sheet layer, both of which are made of polydimethylsiloxane; one end of the annular wall is connected to the peripheral edge of the mold sheet layer, the annular wall and the mold sheet layer are arranged vertically, and a concave structure corresponding to and having the same shape as the pattern on the pre-packaged chip is formed on a side of the mold sheet layer close to the annular wall; the inner side wall of the annular wall is adapted to the peripheral edge of the pre-packaged chip, the axial height of the annular wall is greater than the thickness of the pre-packaged chip, so that when the inner side wall of the other end of the annular wall is fixed to the peripheral edge of the pre-packaged chip, an avoidance gap is reserved between the inner surface of the mold sheet layer and the top of the pre-packaged chip.

2. The splash-proof chip pre-package cover according to claim 1, characterized in that: One end of the annular wall is integrally connected to the peripheral edge of the mold sheet layer.

3. The splash-proof chip pre-package cover according to claim 1, characterized in that: The thickness of the annular wall is uniform.

4. The splash-proof chip pre-package cover according to claim 1, characterized in that: The axial height of the annular wall is uniform.

5. A chip pre-packaging method, characterized in that: The following steps are involved: S1, using the mold substrate to perform the same photolithography coating stripping operation as that used to prepare the pre-packaged chip, and cutting it into the same size as the pre-packaged chip to obtain a mold chip; S2, placing the mold chip into the mold box, pouring polydimethylsiloxane so that the polydimethylsiloxane fills the periphery and top of the mold chip; S3, performing demolding after the polydimethylsiloxane is completely cured to achieve pattern transfer, thereby obtaining a splash-proof chip pre-packaged cover as described in any one of claims 1 to 4; S4, sticking the other end of the ring wall of the anti-splash chip pre-packaging cover to the surrounding side walls of the chip to be packaged in the tube shell, and performing a baking process.

6. A chip prepackaging method according to claim 5, characterized in that: The thickness of the mold substrate is greater than the thickness of the chip substrate used to prepare the pre-packaged chip.

7. A chip prepackaging method according to claim 5, characterized in that: In S1, the same photolithography, coating and stripping operations as those used to prepare pre-packaged chips are performed on the mold substrate, including cleaning the mold substrate, evenly spreading photoresist on the upper surface of the mold substrate, and then performing photolithography, coating and stripping operations, and then dicing after wafer testing to obtain the mold chip.

8. A chip prepackaging method according to claim 5, characterized in that: The inner surface of the mold sheet layer does not contact the top of the chip to be packaged.

9. A chip prepackaging method according to claim 5, characterized in that: The other end surface of the annular wall is flush with the bottom surface of the mold substrate.

10. A chip prepackaging method according to claim 1, characterized in that: The upper surface and the lower surface of the mold substrate are parallel and both are planes, the upper surface and the lower surface of the chip substrate are parallel and both are planes, and the material of the mold substrate is the same as that of the chip substrate.

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