Short-wave infrared detector packaging structure and manufacturing method thereof

Abstract

The invention discloses a short-wave infrared detector packaging structure and a manufacturing method thereof. The short-wave infrared detector packaging structure comprises a high-heat-conduction packaging carrier plate, a ceramic electrode plate, a short-wave infrared detector module, a protection support and an optical window. The bottom surface of the ceramic electrode plate is welded to a first area of the upper surface of the high-thermal-conductivity packaging carrier plate through thermocompression welding, and the short-wave infrared detector module is arranged in a second area of the upper surface of the ceramic electrode plate; the protective bracket is arranged in a peripheral area of a first area on the upper surface of the high-thermal-conductivity packaging carrier plate to form a cavity for accommodating the ceramic electrode plate and the short-wave infrared detector module; the optical window is arranged at the upper end of the protection support. Through an efficient heat conduction structure composed of the high heat conduction packaging carrier plate, the ceramic electrode plate and the protection support, heat during normal work is rapidly conducted out of the packaging structure, so that the size of a thermoelectric cooler in an existing packaging structure is reduced, and the advantages of being good in heat conduction effect and small in size structure are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor electronic device packaging, and particularly to a packaging structure for a short-wave infrared detector and a manufacturing method thereof. Background Art

[0002] With the rapid development of the semiconductor industry, semiconductor photodetectors are increasingly widely used in industries such as monitoring and color sorting. Short-wave infrared detectors have very broad application prospects due to their unique spectral detection capabilities and night vision potential. Currently, the conventional packaging method for short-wave infrared detectors is metal or ceramic packaging. In order to control the temperature of the photodetector module, it is necessary to increase the volume of the packaging structure to implement built-in thermoelectric devices. When coupling the detector with the rear-end movement mechanism, a heat dissipation surface needs to be reserved at the installation surface of the detector to prevent the detector temperature from being too high, which may cause the failure of the thermoelectric device function and the reduction of the detector performance.

[0003] However, the above-mentioned packaging structure of the short-wave infrared detector has a thermoelectric cooler. The thermal conductivity of this component is low, and the packaging cost of the packaging structure is high. Due to the introduction of more coupling interfaces, the volume of the short-wave infrared detector is large, which is not conducive to the wide application of infrared detectors. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of poor thermal conductivity and large volume of the packaging structure of the short-wave infrared detector in the prior art, and to provide a packaging structure for a short-wave infrared detector and a manufacturing method thereof.

[0005] The present invention solves the above technical problem by the following technical solutions:

[0006] In a first aspect, the present invention provides a packaging structure for a short-wave infrared detector, which includes: a high-thermal-conductivity packaging carrier board, a ceramic electrode plate, a short-wave infrared detector module, a protection bracket, and an optical window;

[0007] The bottom surface of the ceramic electrode plate is welded to the upper surface first region of the high-thermal-conductivity packaging carrier board by thermocompression welding, and the short-wave infrared detector module is disposed on the upper surface second region of the ceramic electrode plate; the area of the first region is larger than the area of the second region;

[0008] The protection bracket is disposed on the outer peripheral region of the upper surface first region of the high-thermal-conductivity packaging carrier board to form a chamber for accommodating the ceramic electrode plate and the short-wave infrared detector module;

[0009] The optical window is disposed at the upper end of the protection bracket so that the optical window, the protection bracket, and the high-thermal-conductivity packaging carrier board form a sealed cavity.

[0010] Preferably, a first ball grid array is arranged in the peripheral area of the first area of the high thermal conductivity packaging carrier board, and the high thermal conductivity packaging carrier board is electrically connected to the ceramic electrode plate through the first ball grid array.

[0011] Preferably, a second ball grid array is arranged on the bottom surface of the ceramic electrode plate, and the second ball grid array corresponds to the first ball grid array.

[0012] Preferably, the first area is a gold layer, and the thickness of the gold layer is 1.0 - 1.5 μm.

[0013] Preferably, a target slot is arranged in the peripheral area of the first area on the upper surface of the high thermal conductivity packaging carrier board, and the protection bracket is installed in the target slot.

[0014] Preferably, the short-wave infrared detector module is arranged in the second area of the ceramic electrode plate through epoxy resin glue;

[0015] And / or, the protection bracket is arranged in the target slot through the epoxy resin glue.

[0016] Preferably, the short-wave infrared detector module is electrically connected to the ceramic electrode plate through Au wire bonding.

[0017] Preferably, the short-wave infrared detector module includes a photosensitive chip and a readout circuit, and the photosensitive chip and the readout circuit are electrically connected through metal interconnection bumps.

[0018] Preferably, the high thermal conductivity packaging carrier board is a Cu substrate.

[0019] In a second aspect, the present invention provides a manufacturing method for a short-wave infrared detector packaging structure, and the manufacturing method includes:

[0020] Thermocompression bonding and ball grid array welding are used to weld the bottom surface of the ceramic electrode plate to the first area on the upper surface of the high thermal conductivity packaging carrier board;

[0021] The short-wave infrared detector module is arranged in the second area on the upper surface of the ceramic electrode plate;

[0022] Based on the wire bonding process, the electrical signals of the short-wave infrared detector module are led out to the ceramic electrode plate;

[0023] The protection bracket is installed in the peripheral area of the first area of the high thermal conductivity packaging carrier board so that a chamber is formed to accommodate the ceramic electrode plate and the short-wave infrared detector module;

[0024] The optical window is installed at the upper end of the protection bracket so that the optical window, the protection bracket, and the high thermal conductivity packaging carrier board form a sealed cavity.

[0025] The positive and progressive effects of the present invention are as follows: A packaging structure for a short-wave infrared detector and a manufacturing method thereof provided by the present invention. The packaging structure for the short-wave infrared detector forms an efficient heat conduction structure through a high thermal conductivity packaging carrier board, a ceramic electrode plate, and a protection bracket, and quickly conducts the heat generated during the normal operation of the short-wave infrared detector to the outside of the packaging structure, thereby saving the volume position of the thermoelectric cooling device inside the existing packaging structure, reducing the packaging cost, and achieving the advantages of good heat conduction effect and small volume structure. Description of the Drawings

[0026] Figure 1 It is the first structural schematic diagram of the packaging structure of the short-wave infrared detector in Embodiment 1.

[0027] Figure 2 It is the second structural schematic diagram of the packaging structure of the short-wave infrared detector in Embodiment 1.

[0028] Figure 3 It is the third structural schematic diagram of the packaging structure of the short-wave infrared detector in Embodiment 1.

[0029] Figure 4 It is the flow chart of the manufacturing method of the packaging structure of the short-wave infrared detector in Embodiment 2.

[0030] Figure 5 It is the flow chart of the completion of the packaging of the short-wave infrared detector and the realization of the electrical performance test in the manufacturing method of the packaging structure of the short-wave infrared detector in Embodiment 2.

[0031] Description of the Reference Numerals:

[0032] 1 - High thermal conductivity packaging carrier board, 2 - Ceramic electrode plate, 3 - Short-wave infrared detector module, 4 - Protection bracket, 5 - Optical window, 6 - Thermocompression welding area between the high thermal conductivity packaging carrier board and the ceramic electrode plate, 7 - Connection electrode between the high thermal conductivity packaging carrier board and the ceramic electrode plate, 8 - Target slot, 9 - Connection interface between the short-wave infrared detector and the movement. Detailed Embodiments

[0033] The present invention will be further described below by way of examples, but the present invention is not limited to the scope of the described examples.

[0034] Embodiment 1

[0035] As Figure 1 shown, it is the packaging structure of the short-wave infrared detector in Embodiment 1 of the present invention. The packaging structure of the short-wave infrared detector includes: a high thermal conductivity packaging carrier board 1, a ceramic electrode plate 2, a short-wave infrared detector module 3, a protection bracket 4, and an optical window 5;

[0036] The bottom surface of the ceramic electrode plate 2 is welded to the upper surface of the first area of the high - thermal - conductivity encapsulation carrier board 1 by thermocompression welding, and the short - wave infrared detector module 3 is arranged in the second area on the upper surface of the ceramic electrode plate 2; the area of the first area is larger than that of the second area;

[0037] The protection bracket 4 is arranged in the peripheral area of the first area on the upper surface of the high - thermal - conductivity encapsulation carrier board 1 to form a chamber for accommodating the ceramic electrode plate 2 and the short - wave infrared detector module 3;

[0038] The optical window 5 is arranged at the upper end of the protection bracket 4 so that the optical window 5, the protection bracket 4 and the high - thermal - conductivity encapsulation carrier board 1 form a sealed cavity.

[0039] Among them, a first ball grid array is arranged in the peripheral area of the first area of the high - thermal - conductivity encapsulation carrier board 1, and the high - thermal - conductivity encapsulation carrier board 1 is electrically connected to the ceramic electrode plate 2 through the first ball grid array. A second ball grid array is arranged on the bottom surface of the ceramic electrode plate 2, and the second ball grid array corresponds to the first ball grid array.

[0040] The high - thermal - conductivity encapsulation carrier board 1 is a high - thermal - conductivity PCB bottom board, usually using a high - thermal - conductivity metal as the substrate, and leaving a heat sink or a refrigeration device installation position on the back. A square first area is reserved in the center area of the front surface of the high - thermal - conductivity encapsulation carrier board 1, and this first area is used to represent the solder - coating area of the high - thermal - conductivity encapsulation carrier board 1 for welding with the ceramic electrode plate 2, and the mechanical and thermal connection with the ceramic electrode plate 2 can be realized through the first area. The protection bracket 4 is a metal encapsulation pipe wall, and the protection bracket 4 is arranged in the peripheral area of the first area to form a chamber, so that the ceramic electrode plate 2 and the short - wave infrared detector module 3 can be accommodated at the same time. The optical window 5 is arranged at the upper end part of the protection bracket 4 but does not penetrate the protection bracket 4, and the center positions of the protection bracket 4 and the optical window 5 coincide with each other, and this optical window 5 can perform corresponding antireflection for the response band of the short - wave infrared detector module 3.

[0041] As Figure 2 shown, the positions of the first ball grid array and the second ball grid array correspond to each other one by one to realize the electrical connection between the ceramic electrode plate 2 and the high - thermal - conductivity encapsulation carrier board 1. The second ball grid array pre - arranged on the back of the ceramic electrode plate 2 has the same structure as the first ball grid array pre - arranged on the upper surface of the high - thermal - conductivity encapsulation carrier board 1, thus forming the connection electrode 7 between the high - thermal - conductivity encapsulation carrier board and the ceramic electrode plate.

[0042] It should be noted that the thickness of the thermocompression welding area 6 between the high - thermal - conductivity encapsulation carrier board and the ceramic electrode plate is set according to the actual thermocompression welding process, and it is sufficient to ensure the growth and effective adsorption of solder for the first ball grid array and the second ball grid array, and it is usually not less than 50μm.

[0043] The traditional packaging form of short-wave infrared detectors takes heat dissipation requirements into consideration, and usually adopts metal or ceramic tube shells to package the short-wave infrared detector module, which has high packaging costs; it is necessary to add thermoelectric cooling devices to achieve a good temperature control effect, but the components will occupy the internal space of the short-wave infrared detector packaging structure, resulting in a large volume. The above-mentioned short-wave infrared detector packaging structure realizes the packaging of the short-wave infrared detector module through an efficient thermal conductive structure composed of a high thermal conductivity packaging carrier, a ceramic electrode plate and a protective bracket. Compared with the existing packaging structure composed of metal or ceramic, by introducing a high thermal conductivity packaging carrier, and using hot pressing welding to complete the connection between the high thermal conductivity packaging carrier and the ceramic electrode plate, the thermal conductivity of the packaging structure is enhanced while reducing the electrical output path of the short-wave infrared detector module, eliminating the thermoelectric cooling device in the traditional structure, and quickly exporting the heat generated by the short-wave infrared detector during normal operation to the outside of the packaging structure, reducing the packaging cost while improving the integration of the short-wave infrared detector; using a high thermal conductivity packaging carrier as a detector mounting plate also facilitates the integration and debugging of the short-wave infrared detector and the movement PCB board, and reduces the time required for assembly and adjustment of the movement.

[0044] like Figure 2 As shown, a target slot 8 is set on the peripheral area around the first area of ​​the high thermal conductivity packaging carrier 1 , and the protection bracket 4 is installed in the target slot 8 .

[0045] The protection bracket 4 can be a metal packaging tube wall, which is installed in the target slot corresponding to the installation of the high thermal conductivity PCB board, so as to enhance the protection effect of the short-wave infrared detector module.

[0046] In one embodiment, the protection bracket 4 may be disposed in the target slot 8 by epoxy resin glue.

[0047] In one embodiment, the first region is a gold layer, and the thickness of the gold layer is 1.0-1.5 μm.

[0048] In one embodiment, the short-wave infrared detector module 3 is disposed on the second region of the ceramic electrode plate 2 by epoxy resin glue.

[0049] In one embodiment, the short-wave infrared detector module 3 is electrically connected to the ceramic electrode plate 2 through Au wire bonding.

[0050] In one embodiment, the short-wave infrared detector module 3 includes a photosensitive chip and a readout circuit, and the photosensitive chip and the readout circuit are electrically connected through metal interconnect bump coupling.

[0051] The short-wave infrared detector module 3 is composed of a photosensitive chip and a readout circuit. Through the flip-chip bonding process, after the photosensitive chip is coupled with the metal interconnect bumps on the readout circuit, electrical connection is achieved. After receiving light irradiation in a specific wavelength band, photons are converted into electrical signals in the photosensitive chip. After being amplified, processed, and read by the readout circuit, they are output as the response signal of the short-wave infrared detector module.

[0052] In one embodiment, the high thermal conductivity packaging carrier 1 is a Cu substrate.

[0053] It should be noted that the high thermal conductivity packaging carrier 1 can also be a high thermal conductivity ceramic substrate, and the material of the high thermal conductivity packaging carrier 1 is not specifically limited in this embodiment.

[0054] As Figure 3 shown, the connection interfaces 9 between the short-wave infrared detector and the movement are symmetrically arranged on both sides of the high thermal conductivity packaging carrier 1. An electrical test system is used to perform electrical performance tests on the packaged short-wave infrared detector through the connection interfaces 9 between the short-wave infrared detector and the movement.

[0055] In this embodiment, a short-wave infrared detector packaging structure is provided. Through an efficient heat conduction structure composed of a high thermal conductivity packaging carrier, a ceramic electrode plate, and a protection bracket, the heat generated during the normal operation of the short-wave infrared detector is quickly exported to the outside of the packaging structure, thereby saving the volume position of the thermoelectric cooling device in the existing packaging structure, reducing the packaging cost, and achieving the advantages of good heat conduction effect and small volume structure.

[0056] Embodiment 2

[0057] As Figure 4 shown, it is a manufacturing method of the short-wave infrared detector packaging structure according to Embodiment 1 of the present invention. The manufacturing method includes:

[0058] S101. Thermally compress and ball grid array weld the bottom surface of the ceramic electrode plate to the first area on the upper surface of the high thermal conductivity packaging carrier;

[0059] S102. Place the short-wave infrared detector module on the second area on the upper surface of the ceramic electrode plate;

[0060] S103. Lead out the electrical signals of the short-wave infrared detector module to the ceramic electrode plate based on the wire bonding process;

[0061] S104. Install the protection bracket on the peripheral area of the first area of the high thermal conductivity packaging carrier so as to form a chamber to accommodate the ceramic electrode plate and the short-wave infrared detector module;

[0062] S105. Install the optical window on the upper end of the protection bracket so that the optical window, the protection bracket, and the high thermal conductivity packaging carrier form a sealed cavity.

[0063] Regarding the above steps S101 - S105, the high - thermal - conductivity packaging carrier is a high - thermal - conductivity PCB bottom plate, which usually uses a high - thermal - conductivity metal as the substrate and has a heat sink or a refrigeration device installation position on the back. A square first area is reserved in the center area of the front surface of the high - thermal - conductivity packaging carrier. This first area is used to represent the solder coating area where the high - thermal - conductivity packaging carrier 1 is welded to the ceramic electrode plate, and through the first area, mechanical and thermal connections with the ceramic electrode plate 2 can be achieved. The protection bracket is a metal - encapsulated tube wall, and the protection bracket is arranged in the peripheral area of the first area to form a chamber so as to accommodate the ceramic electrode plate and the short - wave infrared detector module simultaneously. The optical window is arranged at the upper part of the protection bracket but does not penetrate the protection bracket, and the center positions of the protection bracket and the optical window coincide with each other. This optical window can enhance the light transmittance corresponding to the response band of the short - wave infrared detector module.

[0064] In an optional embodiment, as Figure 5 shown, it is a flowchart for the completion of the short - wave infrared detector packaging and the realization of electrical performance testing. Specifically, for the high - thermal - conductivity packaging carrier (the high - thermal - conductivity PCB bottom plate is shown in the figure), a Cu substrate is selected, the substrate is exposed in the thermocompression bonding area, and tin is grown on the substrate. Tin is grown on the surface of the electrode connection area of the high - thermal - conductivity PCB bottom plate, and each electrode is led out to the detector and the movement electrical connection interface through the internal leads of the PCB board. After completing the connection between the high - thermal - conductivity PCB bottom plate and the ceramic electrode plate (the multi - layer ceramic electrode plate is shown in the figure) using the thermocompression bonding process, a short - wave infrared detector module with a size of 640×512 is pasted in the center area of the multi - layer ceramic electrode plate using epoxy resin glue. The metal - encapsulated tube wall is mounted on the outside of the high - thermal - conductivity PCB bottom plate using epoxy resin glue. After the mounting is completed, the electrical leads of the short - wave infrared detector module are led out to the multi - layer ceramic electrode plate using the Au wire bonding process. After curing, the optical window and the detector assembly are placed in a nitrogen environment, and the optical window is mounted using epoxy resin glue to complete the packaging of the short - wave infrared detector module. Finally, an electrical testing system is used to test the electrical performance of the packaged short - wave infrared detector.

[0065] This embodiment provides a manufacturing method for the packaging structure of a short - wave infrared detector. Using thermocompression bonding to complete the connection between the high - thermal - conductivity packaging carrier and the ceramic electrode plate enhances the thermal conductivity of the packaging structure while reducing the electrical output path of the short - wave infrared detector module; eliminating the thermoelectric cooling device in the traditional structure reduces the packaging cost and improves the integration of the short - wave infrared detector packaging structure; using the high - thermal - conductivity packaging carrier as the mounting plate of the detector facilitates the integration and debugging of the short - wave infrared detector and the movement PCB, and further reduces the time required for the assembly and debugging of the movement.

[0066] Although the specific embodiments of the present invention have been described above, those skilled in the art should understand that this is only an example, and the protection scope of the present invention is defined by the appended claims. Without departing from the principle and essence of the present invention, those skilled in the art can make various changes or modifications to these embodiments, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A packaging structure for a short-wave infrared detector, characterized in that, The short-wave infrared detector packaging structure includes: a high thermal conductivity packaging carrier, a ceramic electrode plate, a short-wave infrared detector module, a protection bracket, and an optical window; The bottom surface of the ceramic electrode plate is welded to the first area of the upper surface of the high thermal conductivity packaging carrier by thermocompression bonding, and the short-wave infrared detector module is arranged in the second area of the upper surface of the ceramic electrode plate; the area of the first area is larger than that of the second area; The protection bracket is arranged in the peripheral area of the first area on the upper surface of the high thermal conductivity packaging carrier to form a chamber for accommodating the ceramic electrode plate and the short-wave infrared detector module; The optical window is arranged at the upper end of the protection bracket so that the optical window, the protection bracket, and the high thermal conductivity packaging carrier form a sealed cavity.

2. The short-wave infrared detector packaging structure according to claim 1, characterized in that, A first ball grid array is arranged in the peripheral area of the first area of the high thermal conductivity packaging carrier, and the high thermal conductivity packaging carrier is electrically connected to the ceramic electrode plate through the first ball grid array.

3. The short-wave infrared detector packaging structure according to claim 2, wherein, A second ball grid array is arranged on the bottom surface of the ceramic electrode plate, and the second ball grid array corresponds to the first ball grid array.

4. The short-wave infrared detector packaging structure according to claim 1, wherein The first area is a gold layer, and the thickness of the gold layer is 1.0 - 1.5 μm.

5. The short-wave infrared detector packaging structure according to claim 1, characterized in that A target slot is arranged in the peripheral area of the first area on the upper surface of the high thermal conductivity packaging carrier, and the protection bracket is installed in the target slot.

6. The short-wave infrared detector packaging structure according to claim 5, wherein The short-wave infrared detector module is arranged in the second area of the ceramic electrode plate through epoxy resin glue; And / or, the protection bracket is arranged in the target slot through the epoxy resin glue.

7. The short-wave infrared detector packaging structure according to claim 1, characterized in that, The short-wave infrared detector module is electrically connected to the ceramic electrode plate through Au wire bonding.

8. The short-wave infrared detector packaging structure according to claim 1, wherein The short-wave infrared detector module includes a photosensitive chip and a readout circuit, and the photosensitive chip and the readout circuit are electrically connected through metal interconnection bumps.

9. The short-wave infrared detector packaging structure according to claim 1, characterized in that The high thermal conductivity packaging carrier is a Cu substrate.

10. A manufacturing method of a packaging structure for a short-wave infrared detector, characterized in that, The manufacturing method includes: Welding the bottom surface of the ceramic electrode plate to the first area of the upper surface of the high thermal conductivity packaging carrier by thermocompression bonding and ball grid array; Arranging the short-wave infrared detector module in the second area of the upper surface of the ceramic electrode plate; Leading out the electrical signals of the short-wave infrared detector module to the ceramic electrode plate based on the wire bonding process; Installing the protection bracket in the peripheral area of the first area of the high thermal conductivity packaging carrier so that a chamber is formed to accommodate the ceramic electrode plate and the short-wave infrared detector module; Installing the optical window at the upper end of the protection bracket so that the optical window, the protection bracket, and the high thermal conductivity packaging carrier form a sealed cavity.

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