Infrared detector chip heat conduction substrate structure and chip assembly

Abstract

The utility model relates to an infrared detector chip heat conduction substrate structure and a chip assembly, the heat conduction substrate structure comprises a frame, a substrate and a cold table, and the frame is provided with a through hole; the substrate is mounted on the frame; the cooling table is located on the back face of the substrate, the substrate is connected with the cooling table, and the substrate or the cooling table is arranged in the through hole and used for transmitting heat of the heating element on the front face of the frame to the cooling table on the back face of the frame through the through hole and the substrate. According to the infrared detector chip heat conduction substrate structure provided by the utility model, the substrate is connected with the cooling table, and the substrate or the cooling table is arranged in the through hole in the frame, so that heat of the heating element on the front surface of the frame is transmitted to the cooling table on the back surface of the frame through the through hole and the substrate; the heat generated by the heating element can be directly transmitted to the cooling table through the substrate, so that shorter cooling time can be realized, and faster focal plane temperature reaching can be realized; the temperature consistency of the focal plane is enhanced, so that the influence of temperature difference on the imaging effect is reduced; and the use of adhesives is reduced, and the vacuum degree reliability is enhanced.

Description

TECHNICAL FIELD

[0001] The utility model relates to chip packaging technical field, in particular to a kind of infrared detector chip heat-conducting substrate structure. BACKGROUND

[0002] Current high precision, high sensitivity and other excellent performance infrared detector is refrigeration infrared focal plane detector, and it has important application in military, aerospace, fire prevention warning and other fields.In recent years, the development of small unmanned aerial vehicle, micro-nano satellite, air defense system and other fields puts forward further requirements such as lighter, faster start, better imaging to refrigeration infrared focal plane detector.For this, the industry mainly uses ceramic material with smaller density Al2O3, AlN as the structure form of detector chip substrate frame to realize lightweight design.

[0003] However, using Al2O3, AlN and other ceramic materials still has large thermal mass, which is a negative factor for cooling time.In addition, the existing mode is to bond the infrared detector chip to the ceramic frame, and then bond the ceramic frame to the cold table, which uses a large amount of adhesive, which can cause outgassing problem and have negative impact on the vacuum degree of dewar, and also increase the thermal resistance. SUMMARY

[0004] The utility model provides a kind of infrared detector chip heat-conducting substrate structure for solving at least one technical problem described above.

[0005] The utility model provides a kind of infrared detector chip heat-conducting substrate structure, comprising:

[0006] frame, the frame is set with through-hole;

[0007] base plate, the base plate is installed on the frame;

[0008] cold table, the cold table is located at the back of the base plate, the base plate is connected with the cold table, the base plate or the cold table is arranged in the through-hole, for the heat of the frame front surface heating element is transferred to the cold table on the back of the frame through the through-hole and base plate.

[0009] In an embodiment, the cold table is arranged in the through-hole, the cold table is arranged on the back of the frame, the outer side wall of the cold table is fixedly connected with the inner side wall of the through-hole, and the base plate is arranged on the front of the frame.

[0010] In an embodiment, the front of the frame is provided with a sunken groove, the through-hole is located in the sunken groove, and the base plate is operatively arranged in the sunken groove.

[0011] In one embodiment, the sink groove is provided with a support platform, and the substrate has a gap with the bottom surface of the sink groove, and the back surface of the substrate is provided with a first boss connected with the cold platform.

[0012] In one embodiment, the support platform is multiple, and the support platform is arranged around the bottom surface of the sink groove.

[0013] In one embodiment, the number of the support platform is eight, and one support platform is arranged at each corner and side edge of the bottom surface of the sink groove.

[0014] In one embodiment, the substrate is arranged in the through hole, and the back surface of the substrate is provided with a first boss connected with the cold platform.

[0015] In one embodiment, the end surface of the substrate covers the through hole, and the front surface of the substrate is provided with a second boss arranged in the through hole.

[0016] In one embodiment, the material of the substrate is diamond.

[0017] A chip assembly comprises a chip and the substrate structure of any one of the above technical solutions, and the chip is combined with the substrate by bonding.

[0018] Compared with the prior art, the infrared detector chip heat-conducting substrate structure has the following advantages:

[0019] The infrared detector chip heat-conducting substrate structure has the following advantages: the substrate is connected with the cold platform, the substrate or the cold platform is arranged in the through hole on the frame, the heat of the front surface heating element of the frame is transmitted to the cold platform on the back surface of the frame through the through hole and the substrate, the heat generated by the heating element can be directly transmitted to the cold platform through the substrate, shorter cooling time can be realized, the focal plane can be heated faster, the focal plane temperature consistency is enhanced, the influence of temperature difference on imaging effect is reduced, the use of adhesive is reduced, and the vacuum degree reliability is enhanced.

[0020] The substrate is installed in the sink groove, the substrate is bonded on the support platform by bonding, the substrate has a gap with the bottom surface of the sink groove, the temperature consistency of the substrate is ensured, the first boss is in contact with the cold platform while the substrate is in contact with the support platform, the substrate can be supported by the support platform and the first boss while ensuring temperature transmission, and the installation strength of the substrate is ensured.

[0021] The second boss on the substrate is arranged in the through hole, and then the chip and the second boss are embedded in the through hole together, which is beneficial to reduce the thickness of the frame, increase the area of the substrate, improve the heat dissipation effect, and further reduce the thermal mass of the overall structure, so that the cooling time of the overall structure and the chip is shorter, and the time for cooling to the target temperature is shortened.

[0022] The connection mode of the chip and the substrate adopts surface sputtering deposition of a metal layer, and is combined through atomic diffusion bonding, which reduces the thermal resistance between the chip and the substrate, reduces the use of adhesive, and reduces the problem of affecting the vacuum degree caused by the outgassing of the adhesive. BRIEF DESCRIPTION OF DRAWINGS

[0023] In the following, the utility model will be described in more detail based on the embodiments and with reference to the drawings.

[0024] Figure 1 is an explosion view of the first embodiment of the infrared detector chip heat-conducting substrate structure;

[0025] Figure 2 is a sectional view of the first embodiment of the infrared detector chip heat-conducting substrate structure;

[0026] Figure 3 is a schematic view of the back surface structure of the substrate in the first embodiment of the infrared detector chip heat-conducting substrate structure;

[0027] Figure 4 is an explosion view of the second embodiment of the infrared detector chip heat-conducting substrate structure;

[0028] Figure 5 is a schematic view of the side surface structure of the substrate in the second embodiment of the infrared detector chip heat-conducting substrate structure.

[0029] Reference signs:

[0030] 10 - frame; 11 - through hole; 12 - sunken groove; 13 - support table;

[0031] 20 - substrate; 21 - first boss; 22 - second boss;

[0032] 30 - cold table;

[0033] 40 - chip. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0035] It should be noted that all directionality indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative position relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directionality indications also change accordingly.

[0036] In addition, the description involving "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions of various embodiments can be combined with each other, but it must be based on the realization of ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, and is not within the protection scope required by the present application.

[0037] The utility model will be further described below with reference to the drawings.

[0038] As shown in Figure 1 , Figure 4 The utility model provides a kind of infrared detector chip heat-conducting substrate structure, including frame 10, substrate 20 and cold table 30, through hole 11 is set on frame 10, for a part of heat conduction path, substrate 20 is installed on frame 10, generally, chip 40 is installed in the front of substrate 20, cold table 30 is installed in the back of substrate 20, cold table 30 is fixedly connected with substrate 20, in the embodiment, it is generally connected with cold table 30 by adhesive bonding mode;Important is, a part of substrate 20 or cold table 30 is arranged in through hole 11, it is guaranteed that the heat generated from the front heat-generating element of frame 10 can be efficiently transferred to cold table 30 located in the back of frame 10 by through hole 11 and substrate 20, to realize effective heat dissipation management, so that the heat generated by heat-generating element can be directly transferred to cold table 30 by substrate 20, more reduce the thermal mass of overall structure, so that the cooling time of overall structure and chip is shorter, the time consumption of cooling to target temperature is shortened, and faster focal plane to temperature is realized;Enhance focal plane temperature consistency, to reduce the influence of temperature difference on imaging effect;Reduce the use of adhesive, enhance the reliability of vacuum degree.

[0039] In the existing example, the cold table 30 refers to a structure for cooling electronic components or optical devices in a thermal management system, specifically, the cold table 30 can be a low-temperature platform directly connected with a refrigeration unit (such as a Stirling refrigerator, a thermoelectric cooler, a liquid nitrogen cooling system, etc.), or a component indirectly cooled through a heat-conducting material, the cold table 30 has good thermal conductivity, can quickly take away heat, and maintain a stable low-temperature environment.

[0040] The material of the substrate 20 is diamond, the diamond material substrate 20 has lower density, better thermal conductivity, and lower specific heat capacity, can reduce the use area of the frame 10, and reduce the thermal load; the material of the frame 10 is ceramic, the ceramic frame 10 has small size change when the temperature changes, and prevents electrical short circuit, reduces heat transfer from the outside to the cold table 30.

[0041] In one embodiment, as shown in Figure 1 , Figure 2 , the substrate 20 is located on the front surface of the frame 10, and the cold table 30 is located on the back surface of the frame 10, the cold table 30 is arranged in the through hole 11, and then the outer side wall of the cold table 30 and the inner side wall of the through hole 11 are bonded by an adhesive, the substrate 20 and the cold table 30 are bonded, forming a heat conduction path of the chip 40, the substrate 20, and the cold table 30, and the integration of the chip 40, the substrate 20, and the cold table 30 on the frame 10 is higher.

[0042] Further, a sunken groove 12 is arranged on the front surface of the frame 10, the through hole 11 is located in the sunken groove 12 and is specifically arranged on the bottom surface of the sunken groove 12, the substrate 20 is operatively arranged in the sunken groove 12, and a part or the whole of the substrate 20 is embedded in the sunken groove 12, which can effectively reduce the overall thickness.

[0043] Further, as shown in Figures 1-3 , a support table 13 is arranged in the sunken groove 12, the substrate 20 is placed in the sunken groove 12 and is placed on the support table 13, so that the substrate 20 has a gap with the bottom surface of the sunken groove 12, preventing the temperature distribution of the substrate 20 from being affected by the frame 10, ensuring the temperature consistency of the substrate 20, and a first boss 21 is arranged on the back surface of the substrate 20, the first boss 21 and the cold table 30 are bonded by an adhesive, and the substrate 20 is bonded with the support table 13, so that the substrate 20 is in contact with the support table 13 and the first boss 21 is in contact with the cold table 30, so that the substrate 20 can ensure temperature transmission, and the support table 13 and the first boss 21 can also support the substrate 20, ensuring the installation strength of the substrate 20.

[0044] Specifically, the support table 13 is multiple, and the number of the support table 13 is 8 in the embodiment, the support table 13 is arranged on the bottom surface of the sinking groove 12, and one support table 13 is arranged on each corner and each side of the bottom surface of the sinking groove 12, so that each corner and each side of the substrate 20 is supported by one support table 13, and the stability of the substrate 20 is improved.

[0045] In another embodiment, as shown in Figure 4 、 Figure 5 The substrate 20 is arranged in the through hole 11, the back surface of the substrate 20 is provided with the first boss 21, the first boss 21 is connected with the cold table 30, and in the embodiment, the connection mode of the substrate 20 and the cold table 30 is also the mode that the first boss 21 is bonded with the cold table 30, the substrate 20 is arranged in the through hole 11, then the chip 40 is bonded with the substrate 20, or a part of the chip 40 is embedded in the through hole 11, so that the overall thickness of the chip 40, the substrate 20 and the frame 10 can be greatly reduced, the thickness of the frame 10 can be made thinner, the frame 10 can be arranged as a ceramic thin layer in the embodiment, and the area of the substrate 20 can be made larger, so that the heat dissipation effect of the substrate 20 is improved, and the cooling time is shortened.

[0046] Further, the end surface of the substrate 20 covers the through hole 11, the second boss 22 is arranged on the front surface of the substrate 20, the second boss 22 is arranged in the through hole 11, then the chip 40 is bonded with the second boss 22, the area of the second boss 22 is greater than or equal to the area of the chip 40 in the embodiment, preferably, the area of the second boss 22 is the same as that of the chip 40, so that the circuit arrangement of the chip 40 is facilitated, the end surface of the substrate 20 covers the through hole 11, so that the area of the substrate 20 can be arranged larger, and the temperature generated by the chip 40 is transmitted to the back surface of the frame 10, so that the heat dissipation of the chip 40 is facilitated.

[0047] The utility model also provides a chip assembly, including chip 40 and above -mentioned technical scheme any one of the substrate structure, chip 40 is combined with substrate 20 through bonding mode, specifically including:

[0048] The chip 40 is directly bonded with the substrate 20, and the cold table 30 is embedded in the through hole 11; or,

[0049] The second boss 22 on the substrate 20 is arranged in the through hole 11, the substrate 20 is located on the back surface of the frame 10, then the chip 40 is bonded with the second boss 22, and when being arranged, a part of the chip 40 can be embedded in the through hole 11, and the second boss 22 is completely embedded in the through hole 11; or the second boss 22 is completely embedded in the through hole 11, and the chip 40 is located outside the through hole 11.

[0050] The connection mode of the chip 40 and the substrate 20 adopts surface sputtering deposition of a metal layer, is combined through atomic diffusion bonding, reduces the thermal resistance between the chip 40 and the substrate 20, and reduces the use of adhesive, and reduces the problem of the influence of the adhesive outgassing on the vacuum degree.

[0051] Although the utility model has been described with reference to the preferred embodiments, various improvements can be made and equivalent parts can be replaced without departing from the scope of the utility model. In particular, the technical features mentioned in each embodiment can be combined in any way as long as there is no structural conflict. The utility model is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An infrared detector chip heat conducting substrate structure, characterized by, The application relates to a substrate structure for a chip, which comprises the following parts: a frame with a through hole; a substrate installed on the frame; a cold table located at the back of the substrate, the substrate being connected with the cold table, the substrate or the cold table being arranged in the through hole to transfer the heat of the front heat element of the frame to the cold table at the back of the frame through the through hole and the substrate.

2. The infrared detector chip heat conducting substrate structure of claim 1, wherein, The cold table is arranged in the through hole and at the back of the frame, and the outer side wall of the cold table is fixedly connected with the inner side wall of the through hole, and the substrate is arranged at the front of the frame.

3. The infrared detector chip heat conducting substrate structure of claim 2, wherein, The front of the frame is provided with a sunken groove, the through hole is located in the sunken groove, and the substrate is operatively arranged in the sunken groove.

4. The infrared detector chip heat conducting substrate structure of claim 3, wherein, The sunken groove is provided with a support table, and the substrate has a gap with the bottom surface of the sunken groove, the back of the substrate is provided with a first boss, the first boss is connected with the cold table, and the substrate is in contact with the support table while the first boss is in contact with the cold table.

5. The infrared detector chip heat conducting substrate structure of claim 4, wherein, The support table is provided around the bottom surface of the sunken groove.

6. The infrared detector chip heat conducting substrate structure of claim 5, wherein, The number of the support tables is eight, and one support table is arranged at each corner and side edge of the bottom surface of the sunken groove.

7. The infrared detector chip heat conducting substrate structure of claim 1, wherein, The substrate is arranged in the through hole, the back of the substrate is provided with a first boss, and the first boss is connected with the cold table.

8. The infrared detector chip heat conducting substrate structure of claim 7, wherein, The end surface of the substrate covers the through hole, the front of the substrate is provided with a second boss, and the second boss is arranged in the through hole.

9. The infrared detector chip heat conducting substrate structure according to any of claims 1 to 8, characterized in that The material of the substrate is diamond.

10. A chip assembly, characterized by The application further relates to a chip and the substrate structure as claimed in any one of claims 1-8, and the chip is combined with the substrate by bonding.

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