MOS device packaging structure

Abstract

The utility model provides a metal oxide semiconductor (MOS) device packaging structure, which relates to the field of MOS device packaging, and comprises a packaging shell, a packaging cover and an MOS chip, the inner sides of the packaging shell and the packaging cover are packaged and wrapped with the MOS chip, the inner side surface of the packaging shell is fixedly provided with a metal supporting sheet, the lower surface of the MOS chip is bonded with the metal supporting sheet through a soldering paste layer, and the metal supporting sheet is fixed on the packaging shell. A heat-conducting fin is fixedly embedded in the inner side of the packaging cover, a graphite heat dissipation film is fixed on the upper surface of the packaging cover, a heat-conducting fin is attached to the lower end face of the graphite heat dissipation film, a ceramic heat-conducting column is fixed to the lower end face of the heat-conducting fin, and the lower column face of the ceramic heat-conducting column is tightly attached to the soldering paste layer through a silica gel sheet. According to the utility model, the problem that in the prior art, the ceramic chip and the protruding block are both located on the bottom surface of the epoxy packaging body, and when the bottom surface of the MOS device is attached to the electronic device, the conducted heat is easy to gather is solved.

Description

Technical Field

[0001] The utility model relates to the field of MOS device packaging, in particular to a MOS device packaging structure. Background Art

[0002] MOS device is an electronic switch, whose switching state is controlled by the gate voltage. When it is turned on, it is conducted by electrons or holes. It has the advantages of simple control and fast switching, so it is widely used in power electronic systems, mainly including switching power supplies and motor drives. After searching, the prior art (Announcement No.: CN202222296643.8) Power MOS device packaging structure, the article records "the utility model power MOS device packaging structure, its metal support sheet further includes a support sub-sheet and an outer extension sub-sheet, the outer extension sub-sheet of the metal support sheet is located outside the epoxy package body, and the upper surface and lower surface of the support sub-sheet of the metal support sheet are respectively provided with The upper and lower bumps improve the bonding force between the epoxy package and the epoxy package, avoid delamination between the supporting sub-piece and the epoxy package, and thus improve the structural stability of the device; in addition, it further provides a protruding block on the lower surface of the ceramic sheet, the protruding block is embedded in the through-area of ​​the supporting sub-piece and extends from the through-area, and the bottom surface of the protruding block of the ceramic sheet is flush with the bottom surface of the epoxy package, which can quickly conduct the heat of the MOS chip to the outside, thereby extending the service life of the device. However, in the prior art, the ceramic sheet and the protruding block are both located on the bottom surface of the epoxy package, and when the bottom surface of the MOS device is in contact with the electronic device, the conducted heat is prone to accumulation. Utility Model Content

[0003] In order to overcome the defects of the prior art, a MOS device packaging structure is provided to solve the problem that in the prior art, the ceramic sheet and the protruding block are both located on the bottom surface of the epoxy package body, and the heat conducted is easily accumulated when the bottom surface of the MOS device is attached to the electronic device.

[0004] To achieve the above object, a MOS device packaging structure is provided, comprising: a packaging shell, a packaging cover and a MOS chip, wherein the packaging shell and the packaging cover are encapsulated with a MOS chip.

[0005] A metal support sheet is fixed to the inner side of the packaging shell, the metal support sheet is bonded to the lower surface of the MOS chip through a solder paste layer, a heat conductive sheet is embedded and fixed to the inner side of the packaging cover, a graphite heat dissipation film is fixed to the upper surface of the packaging cover, a heat conductive sheet is attached to the lower end surface of the graphite heat dissipation film, a ceramic heat conductive column is fixed to the lower end surface of the heat conductive sheet, and the lower column surface of the ceramic heat conductive column is tightly attached to the solder paste layer through a silicone sheet.

[0006] Furthermore, an epitaxial wafer is embedded and fixed on the rear side of the packaging shell; and a through hole is opened on the surface of the epitaxial wafer, and a packaging cover is sealed and fixed on the upper end surface of the packaging shell.

[0007] Furthermore, three groups of metal pins are embedded and fixed in the front end surface of the packaging shell; and the three groups of metal pins are respectively connected to the gate region, source region and drain region of the MOS chip.

[0008] Furthermore, a protective cover is bonded to the upper surface of the packaging cover; and the graphite heat dissipation film is located on the inner side of the protective cover, and the outer side of the protective cover is provided with a dustproof mesh surface.

[0009] Furthermore, the ceramic heat-conducting columns are symmetrically distributed on the left and right sides of the MOS chip, and the silicone sheet is in the shape of an isosceles trapezoidal sheet attached to the upper surface of the solder paste layer.

[0010] Furthermore, the ceramic heat-conducting column, the graphite heat-dissipating film, the heat-conducting sheet and the silicone sheet constitute an upward transfer type heat dissipation structure of the MOS chip.

[0011] Furthermore, the ceramic heat-conducting column, the graphite heat-dissipating film, the heat-conducting sheet and the silicone sheet constitute an upward transfer type heat dissipation structure of the MOS chip.

[0012] The beneficial effect of the utility model is that the MOS device packaging structure of the utility model utilizes the ceramic heat-conducting column, the graphite heat dissipation film and the silicone sheet of the MOS device packaging cover to form a top heat dissipation structure, and the silicone sheet is in contact with the solder paste layer at the bottom of the MOS chip to transfer heat upward to the graphite heat dissipation film for dissipation, thereby preventing the heat of the graphite heat dissipation film from being transferred to the adjacent electronic devices, facilitating the rapid transfer of heat to the outside of the MOS device packaging shell, enhancing the heat transfer effect of the MOS device, and improving the heat dissipation performance of the MOS device packaging structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the three-dimensional structure of the MOS device packaging structure of an embodiment of the utility model.

[0014] Figure 2 It is a front view cross-sectional structural diagram of the MOS device packaging structure according to an embodiment of the utility model.

[0015] Figure 3 It is a schematic diagram of the top view of the MOS device packaging structure of an embodiment of the utility model.

[0016] Figure 4 It is a schematic diagram of the side structure of the ceramic heat-conducting column according to an embodiment of the utility model.

[0017] In the figure: 1. Package shell; 11. Epitaxial wafer; 12. Metal pins; 13. Metal support sheet; 2. Package cover; 21. Protective cover; 22. Dustproof mesh; 3. MOS chip; 31. Solder paste layer; 4. Ceramic thermal conductive column; 41. Graphite heat dissipation film; 42. Thermal conductive sheet; 43. Silicone sheet. DETAILED DESCRIPTION

[0018] Reference Figures 1 to 4 As shown, the utility model provides a MOS device packaging structure, including: a packaging shell 1, a packaging cover 2 and a MOS chip 3, wherein the MOS chip 3 is packaged and wrapped inside the packaging shell 1 and the packaging cover 2.

[0019] A metal support sheet 13 is fixed to the inner side of the packaging shell 1, and the metal support sheet 13 is bonded to the lower surface of the MOS chip 3 through a solder paste layer 31. A heat conductive sheet 42 is embedded and fixed to the inner side of the packaging cover 2, and a graphite heat dissipation film 41 is fixed to the upper surface of the packaging cover 2. The heat conductive sheet 42 is attached to the lower end surface of the graphite heat dissipation film 41, and a ceramic heat conductive column 4 is fixed to the lower end surface of the heat conductive sheet 42. The lower column surface of the ceramic heat conductive column 4 is tightly attached to the solder paste layer 31 through a silicone sheet 43.

[0020] The ceramic thermal conductive column 4, graphite heat dissipation film 41 and silicone sheet 43 of the MOS device packaging cover 2 constitute a top heat dissipation structure, which contacts the solder paste layer 31 at the bottom of the MOS chip 3 through the silicone sheet 43, and transfers heat upward to the graphite heat dissipation film 41 for dissipation, thereby preventing the heat of the graphite heat dissipation film 41 from being transferred to the adjacent electronic devices, facilitating the rapid transfer of heat to the outside of the MOS device packaging shell, enhancing the heat transfer effect of the MOS device, and improving the heat dissipation performance of the MOS device packaging structure.

[0021] In this embodiment, an epitaxial wafer 11 is embedded and fixed on the rear side of the package shell 1; a through hole is opened on the surface of the epitaxial wafer 11, and a package cover 2 is sealed and fixed on the upper end surface of the package shell 1. Three groups of metal pins 12 are embedded and fixed on the front end surface of the package shell 1; and the three groups of metal pins 12 are respectively connected to the gate region, source region and drain region of the MOS chip 3.

[0022] As a preferred embodiment, the epitaxial wafer 11 can adjust the concentration and thickness to achieve the required breakdown voltage of the MOS device. The three groups of metal pins 12 are connected to the gate region, source region and drain region of the MOS chip 3, respectively playing the role of controlling the current, controlling the channel and controlling the output current.

[0023] In this embodiment, a protective cover 21 is bonded to the upper surface of the packaging cover 2 ; and the graphite heat dissipation film 41 is located on the inner side of the protective cover 21 , and a dustproof mesh surface 22 is provided on the outer side of the protective cover 21 .

[0024] As a preferred embodiment, the protective cover 21 is convenient for protecting the graphite heat dissipation film 41 and reducing the degree of damage to the graphite heat dissipation film 41. The dustproof mesh surface 22 plays the role of dustproof, ventilation and heat dissipation.

[0025] In this embodiment, the ceramic heat-conducting columns 4 are symmetrically distributed on the left and right sides of the MOS chip 3, and the silicone sheet 43 is in the shape of an isosceles trapezoidal sheet attached to the upper surface of the solder paste layer 31. Five groups of ceramic heat-conducting columns 4 are arranged between the heat-conducting sheet 42 and the silicone sheet 43; and the five groups of ceramic heat-conducting columns 4 are arranged and distributed in a shape of thick inside and thin outside. The ceramic heat-conducting columns 4, the graphite heat-dissipating film 41, the heat-conducting sheet 42 and the silicone sheet 43 constitute an upward transfer heat dissipation structure of the MOS chip 3.

[0026] As a preferred embodiment, the silicone sheet 43 increases the contact area between the ceramic heat-conducting column 4 and the solder paste layer 31, so that the heat generated by the MOS chip 3 is transferred to the ceramic heat-conducting column 4 through the silicone sheet 43 and the solder paste layer 31, and then transferred to the graphite heat dissipation film 41 for dissipation. The upward transfer heat dissipation structure of the MOS chip 3 prevents the heat of the graphite heat dissipation film from being transferred to the adjacent electronic devices, facilitates the rapid transfer of heat to the outside of the MOS device packaging shell, strengthens the heat transfer effect of the MOS device, and improves the heat dissipation performance of the MOS device packaging structure.

[0027] The MOS device packaging structure of the present invention can effectively solve the problem that heat conducted when the bottom surface of the MOS device is in contact with the electronic device is easily accumulated, avoids the heat transfer of the graphite heat dissipation film to the attached electronic device, facilitates the rapid transfer of heat to the outside of the MOS device packaging shell, strengthens the heat transfer effect of the MOS device, and improves the heat dissipation performance of the MOS device packaging structure, and is suitable for the MOS device packaging structure.

Claims

1. A MOS device packaging structure, comprising: A packaging shell (1), a packaging cover (2) and a MOS chip (3), wherein the MOS chip (3) is packaged and wrapped inside the packaging shell (1) and the packaging cover (2), and is characterized in that: A metal support sheet (13) is fixed to the inner side of the packaging shell (1); the lower surface of the MOS chip (3) is bonded to the metal support sheet (13) via a solder paste layer (31); a heat conductive sheet (42) is embedded and fixed to the inner side of the packaging cover (2); a graphite heat dissipation film (41) is fixed to the upper surface of the packaging cover (2); the lower end surface of the graphite heat dissipation film (41) is bonded to the heat conductive sheet (42); a ceramic heat conductive column (4) is fixed to the lower end surface of the heat conductive sheet (42); and the lower column surface of the ceramic heat conductive column (4) is tightly bonded to the solder paste layer (31) via a silicone sheet (43).

2. A MOS device packaging structure according to claim 1, characterized in that: An epitaxial wafer (11) is embedded and fixed on the rear side of the packaging shell (1); a through hole is provided on the surface of the epitaxial wafer (11); and a packaging cover (2) is sealed and fixed on the upper end surface of the packaging shell (1).

3. A MOS device packaging structure according to claim 1, characterized in that: Three groups of metal pins (12) are embedded and fixed on the front end surface of the packaging shell (1); and the three groups of metal pins (12) are respectively connected to the gate region, source region and drain region of the MOS chip (3).

4. A MOS device packaging structure according to claim 1, characterized in that: A protective cover (21) is bonded to the upper surface of the packaging cover (2); and a graphite heat dissipation film (41) is located inside the protective cover (21); and dustproof mesh surfaces (22) are provided on the outer side surfaces of the protective cover (21).

5. The MOS device packaging structure according to claim 1, characterized in that: The ceramic heat-conducting columns (4) are symmetrically distributed on the left and right sides of the MOS chip (3), and the silicone sheet (43) is in the shape of an isosceles trapezoid and is attached to the upper surface of the solder paste layer (31).

6. The MOS device packaging structure according to claim 1, characterized in that: Five groups of ceramic heat-conducting columns (4) are arranged between the heat-conducting sheet (42) and the silicone sheet (43); and the five groups of ceramic heat-conducting columns (4) are arranged and distributed in a shape of being thick inside and thin outside.

7. The MOS device packaging structure according to claim 1, characterized in that: The ceramic heat-conducting column (4), the graphite heat-dissipating film (41), the heat-conducting sheet (42) and the silicone sheet (43) constitute an upward transfer type heat-dissipating structure of the MOS chip (3).

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