High-power-density laminated ceramic packaging structure

Abstract

The invention provides a high-power-density laminated ceramic packaging structure. The high-power-density laminated ceramic packaging structure comprises a ceramic substrate, a square cavity is formed in the ceramic substrate, a first bonding table, a connecting table and a second bonding table are oppositely arranged on two opposite angles in the ceramic substrate respectively, the first bonding table, the connecting table and the second bonding table are arranged at different heights, a power device is mounted at the bottom of the ceramic substrate, and a plurality of electric plates are stacked on the connecting table. According to the invention, the chips are mounted in the ceramic shell in a multi-layer manner in a stacking manner, so that the power density of the device is improved; and the metal frame is arranged on each layer of the electric plate to form a heat balance design, so that the internal heat balance is ensured, and the heat dissipation function is increased by using the metal frame as a sealing ring.

Description

Technical Field

[0001] The invention relates to a high-power density laminated ceramic packaging structure. Background Art

[0002] With the continuous development of semiconductor technology, electronic devices are becoming increasingly miniaturized and denser. In the field of electronic control switches, the size of switches is decreasing while the control current is increasing. As a result, traditional ceramic tube shells cannot meet the heat dissipation requirements, making it impossible to further reduce the size of the product.

[0003] For example, CN216490437U discloses a ceramic sealed photoelectric isolation switch with high dielectric withstand voltage. Field effect tubes, photovoltaic arrays, and ceramic substrates are distributed and installed at the bottom of a ceramic tube holder, and a certain spacing is set to avoid thermal effects between chips. All chips are arranged at the bottom of the ceramic tube shell to greatly reduce its power density. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a high power density laminated ceramic packaging structure.

[0005] The present invention is achieved through the following technical solutions.

[0006] The present invention provides a high-power density laminated ceramic packaging structure, comprising a ceramic substrate; a square cavity is provided in the ceramic substrate, a first bonding platform, a connecting platform, and a second bonding platform are respectively provided on two diagonal portions of the ceramic substrate, the first bonding platform, the connecting platform, and the second bonding platform are at different heights, a power device is installed at the bottom of the ceramic substrate, a plurality of electric boards are stacked on the connecting platform, each electric board is respectively bonded to the first bonding platform or the second bonding platform adjacent thereto, a metal frame is also provided on the top of the ceramic substrate, the top of the metal frame is closed by a cover plate, a lead column is also installed in the bottom of the ceramic substrate, both ends of the lead column extend out of the two ends of the bottom of the ceramic substrate, and the end outside is connected to a lead fixed to the bottom of the ceramic substrate.

[0007] The second bonding platform and the connecting platform on the two diagonals are respectively connected to the two side walls of the diagonals. The first bonding platform is arranged parallel to the connecting platform and its two sides are respectively connected to the second bonding platform and the connecting platform. The heights of the first bonding platform, the connecting platform and the second bonding platform increase in sequence.

[0008] Two power devices are installed at the bottom of the ceramic substrate, and the two power devices are respectively adjacent to and in contact with the second bonding platform and the first bonding platform on two diagonal corners.

[0009] A metal sheet is arranged between the power device and the ceramic substrate.

[0010] The number of the electrical boards is specifically two, and each of the electrical boards includes a ceramic board and a metal half frame. The metal half frame surrounds one end and both sides of the ceramic board along the front edge of the ceramic board. A bonding area is provided on the other end of the ceramic board, and a device welding area is provided in the middle of the front of the ceramic board; two bottom bonding areas parallel to each other are also provided at both ends of the bottom of the ceramic board, and the ends of the two bottom bonding areas separated from each other are respectively aligned with the edges of the ceramic board.

[0011] The bonding areas and device welding areas on the two boards are set according to the size and polarity of the devices installed thereon. The metal half-frame widths on the two boards are different, and the outer wall width of any one is smaller than the inner wall width of the other.

[0012] Conductive areas are printed on the tops of the first bonding platform, the connecting platform, and the second bonding platform.

[0013] The lead column is made of a ceramic substrate or a plurality of metal wires.

[0014] The beneficial effects of the present invention are as follows: the chips are installed in a ceramic housing in multiple layers by stacking, thereby improving the power density of the device; and a metal frame is arranged on each layer of the electric board to form a thermal balance design to ensure internal thermal balance, and the metal frame is used as a sealing exchange to increase the heat dissipation function. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the present invention;

[0016] Figure 2 It is a schematic diagram of the cross-sectional structure of the shell of the present invention;

[0017] Figure 3 It is a schematic diagram of the top view of the housing structure of the present invention;

[0018] Figure 4 It is a schematic diagram of the facade structure of the shell of the present invention;

[0019] Figure 5 This is a schematic diagram of the front structure of the first electric plate of the present invention;

[0020] Figure 6 This is a schematic diagram of the front structure of the second electric plate of the present invention;

[0021] Figure 7 It is a schematic diagram of the back structure of the first electric plate of the present invention;

[0022] Figure 8 It is a schematic diagram of the back structure of the second electric plate of the present invention;

[0023] Fig. 9 It is a schematic diagram of the side structure of the electric plate of the present invention;

[0024] In the figure: 1-ceramic substrate, 2-first bonding platform, 3-connecting platform, 4-second bonding platform, 5-metal frame, 6-power device, 7-lead column, 8-lead, 9-first electric plate, 10-second electric plate, 11-bonding area, 12-device welding area, 13-ceramic plate, 14-metal half frame, 15-bottom bonding area. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is further described below, but the scope of protection claimed is not limited to the description.

[0026] like Figure 1 As shown, a high power density laminated ceramic packaging structure includes a ceramic substrate 1; a square cavity is provided in the ceramic substrate 1, and a first bonding platform 2, a connecting platform 3, and a second bonding platform 4 are respectively provided on two diagonal corners in the ceramic substrate 1, wherein the first bonding platform 2, the connecting platform 3, and the second bonding platform 4 are at different heights; a power device 6 is installed at the bottom of the ceramic substrate 1, and a plurality of electric boards are stacked on the connecting platform 3, and each electric board is respectively bonded to the first bonding platform 2 or the second bonding platform 4 adjacent thereto; a metal frame 5 is further provided on the top of the ceramic substrate 1, and the top of the metal frame 5 is closed by a cover plate; a lead column 7 is further installed in the bottom of the ceramic substrate 1, and both ends of the lead column 7 extend out of the two ends of the bottom of the ceramic substrate 1, and the end outside is connected to a lead 8 fixed to the bottom of the ceramic substrate 1. The height of the metal frame is between 1 / 4 and 1 / 2 of the height of the product body (excluding the thickness of the metal lead). It is made of metal material. The metal frame replaces the metal sealing ring and part of the ceramic side wall of the traditional structure. Since the heat dissipation capacity of metal is higher than that of ceramic, the metal frame acts as a small radiator. The metal frame and the ceramic cavity are connected by sintering.

[0027] The ceramic cavity is made by traditional ceramic shell manufacturing process, through ceramic lamination, punching, printing, filling and other processes. The metal sheet and metal lead can be molybdenum, copper, kovar alloy, other metals or other metal alloys, etc., and can be the same metal or different metals; according to the internal and external dimensions and technical requirements, the metal sheet and metal lead can also be replaced by metal slurry.

[0028] like Figure 3 and Figure 4As shown, the second bonding platform 4 and the connecting platform 3 on the two diagonals are respectively connected to the two side walls of the diagonals, the first bonding platform 2 is arranged parallel to the connecting platform 3 and is respectively connected to the second bonding platform 4 and the connecting platform 3 on both sides, and the heights of the first bonding platform 2, the connecting platform 3, and the second bonding platform 4 are increased in sequence. The interior of the product is formed into different heights through the ceramic sintering process, and from bottom to top, they are the power device area, the bonding 1 area, the connecting area, and the bonding 2 area; wherein the power device area is used to assemble power devices, and the metal sheet is sintered with the ceramic base, and the bonding 1 area, the connecting area, and the bonding 2 area are printed by slurry printing, electroplating and other processes, wherein the bonding 1 area is the power device electrode connection area, and the assembled power device realizes the connection between the chip surface electrode and the ceramic tube shell through the bonding 1 area; the connection area, the bonding 2 area and the power device area can determine their internal connection relationship according to the internal electrical connection relationship of the actual assembled chip, as well as the connection relationship with the lead.

[0029] The connection area is used for point connection with the first electric plate or the second electric plate, and the connection process can be sintering or bonding. The bonding area 2 is used for connection with the back bonding area of ​​the first electric plate or the second electric plate through a bonding process.

[0030] Two power devices 6 are installed at the bottom of the ceramic substrate 1 , and the two power devices 6 are adjacent to and in contact with the second bonding platform 4 and the first bonding platform 2 on two diagonal sides, respectively.

[0031] A metal sheet is provided between the power device 6 and the ceramic substrate 1 .

[0032] There are two electric boards, each of which includes a ceramic board 13 and a metal half frame 14. The metal half frame 14 surrounds one end and both sides of the ceramic board 13 along the front edge of the ceramic board 13. A bonding area 11 is provided on the other end of the ceramic board 13, and a device welding area 12 is provided in the middle of the front of the ceramic board 13. Two bottom bonding areas 15 parallel to each other are also provided at both ends of the bottom of the ceramic board 13. The separated ends of the two bottom bonding areas 15 are respectively aligned with the edges of the ceramic board 13, so as to facilitate the connection or welding of the electric board and its adjacent bonding area using conductive glue.

[0033] The bonding area 11 and the device welding area 12 on the two boards are set according to the size and polarity of the device installed, and the printed pattern is changed according to the device pattern. The bonding area and the device area can be connected to the back bonding or connection area through the inside of the ceramic as needed to establish an internal three-dimensional connection structure. The internal device area, bonding area, bonding or connection area all use slurry printing technology and electroplating technology. The metal half-frames 14 on the two boards have different widths, and the outer wall width of any one is smaller than the inner wall width of the other.

[0034] Conductive areas are printed on the top of the first bonding platform 2 , the connection platform 3 , and the second bonding platform 4 .

[0035] like Figure 2 As shown, the lead column 7 is made of one or more metal wires on a ceramic substrate. Figure 2 As shown in the figure, the lead is composed of metal wires, which can be one or more metal wires, and are made of metal materials, replacing traditional filling slurry, which is beneficial to further reduce the thermal resistance inside the package; the internal connection metal wire is sintered with the ceramic cavity through the slurry to achieve partial connection of the ceramic cavity; then the internal connection is achieved through solder and the metal sheet, and connected to the metal lead through solder; the metal sheet, the internal connection metal wire, and the metal lead form a small heat sink, while minimizing the internal thermal resistance of the product and achieving internal and external heat dissipation enhancement.

[0036] The present invention improves the installation density of the product by adopting a three-dimensional stacking method through a high-power density laminated ceramic shell and increases the power density by adding a metal heat dissipation structure, thereby realizing shell and tube support for high-power density products. The power density of the product using the shell and tube can reach more than 5000W / cm3, which is more than 1 times that of the existing traditional shell and tube, and the product output current capacity is more than 3 times that of similar products.

Claims

1. A high power density laminated ceramic packaging structure, comprising a ceramic substrate (1), characterized in that: The ceramic substrate (1) is provided with a square cavity, and a first bonding platform (2), a connecting platform (3), and a second bonding platform (4) are respectively arranged opposite to each other at two diagonal positions in the ceramic substrate (1), and the first bonding platform (2), the connecting platform (3), and the second bonding platform (4) are at different heights. A power device (6) is installed at the bottom of the ceramic substrate (1), and a plurality of electric boards are stacked on the connecting platform (3), and each electric board is respectively bonded to the first bonding platform (2) or the second bonding platform (4) adjacent thereto. A metal frame (5) is also provided at the top of the ceramic substrate (1), and the top of the metal frame (5) is closed by a cover plate. A lead column (7) is also installed at the bottom of the ceramic substrate (1), and both ends of the lead column (7) extend out of the two ends of the bottom of the ceramic substrate (1), and the end outside is connected to a lead (8) fixed to the bottom of the ceramic substrate (1).

2. The high power density laminated ceramic package structure according to claim 1, characterized in that: The second bonding platform (4) and the connecting platform (3) on two diagonal corners are respectively connected to the two side walls of the diagonal corners; the first bonding platform (2) is arranged parallel to the connecting platform (3) and is respectively connected to the second bonding platform (4) and the connecting platform (3) on both sides; the heights of the first bonding platform (2), the connecting platform (3) and the second bonding platform (4) are increased in sequence.

3. The high power density laminated ceramic package structure according to claim 1, characterized in that: Two power devices (6) are installed at the bottom of the ceramic substrate (1), and the two power devices (6) are respectively adjacent to and in contact with the second bonding platform (4) and the first bonding platform (2) and the power device (6) at two diagonal positions.

4. The high power density laminated ceramic package structure as claimed in claim 3, characterized in that: A metal sheet is provided between the power device (6) and the ceramic substrate (1).

5. The high power density laminated ceramic package structure according to claim 1, characterized in that: The number of the electric plates is specifically two, each of which comprises a ceramic plate (13) and a metal half frame (14), the metal half frame (14) surrounding one end and both sides of the ceramic plate (13) along the front edge of the ceramic plate (13), a bonding area (11) being provided on the other end of the ceramic plate (13), and a device welding area (12) being provided in the middle of the front of the ceramic plate (13); two bottom bonding areas (15) parallel to each other are also provided at both ends of the bottom of the ceramic plate (13), and the separated ends of the two bottom bonding areas (15) are respectively aligned with the edges of the ceramic plate (13).

6. The high power density laminated ceramic package structure according to claim 5, characterized in that: The bonding area (11) and the device welding area (12) on the two electric boards are arranged according to the size and polarity of the devices installed thereon. The metal half frames (14) on the two electric boards have different widths, and the outer wall width of any one is smaller than the inner wall width of the other.

7. The high power density laminated ceramic package structure according to claim 1, characterized in that: Conductive areas are printed on the tops of the first bonding platform (2), the connecting platform (3) and the second bonding platform (4).

8. The high power density laminated ceramic package structure according to claim 1, characterized in that: The lead column (7) is made of a ceramic substrate (1) and one or more metal wires.

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