A pixel-level packaging structure of an uncooled infrared detector and its manufacturing method

Abstract

The present application discloses a pixel-level packaging structure for an uncooled infrared detector and a manufacturing method thereof, comprising an integrated circuit substrate and a pixel device disposed on the upper surface of the integrated circuit substrate; the pixel device comprises a pixel unit and an air-intake unit disposed on one side of the pixel unit, the air-intake unit comprising a getter layer disposed on the upper surface of the integrated circuit substrate, a support layer, and a sealing layer disposed on the upper surface of the support layer; the cavity in the air-intake unit is connected to the cavity in the pixel unit; or the pixel device comprises a getter layer and a reflective layer disposed on the upper surface of the integrated circuit substrate, and an infrared sensor unit disposed above and corresponding to the reflective layer. The pixel device comprises a pixel unit and an air-intake unit disposed on one side of the pixel unit, the getter layer not being disposed in the pixel unit; or the getter layer in the pixel device does not correspond to the infrared sensor unit, thereby avoiding the influence of the getter layer on the infrared sensor unit and improving the performance of the uncooled infrared detector.

Description

Technical Field

[0001] The present application relates to the field of infrared imaging technology, and in particular to a pixel-level packaging structure of an uncooled infrared detector and a manufacturing method thereof. Background Art

[0002] Pixel-level packaging, as a packaging technology for the fourth-generation uncooled infrared focal plane detector, is the packaging of a single pixel or a series of pixels. The MEMS (Micro-Electro-Mechanical System) manufacturing process is performed on the bottom CMOS (Complementary Metal Oxide Semiconductor) integrated circuit substrate wafer. Compared with wafer-level packaging, pixel-level packaging can save the design and processing of a wafer and does not require a bonding process, which greatly simplifies the production process and saves process time.

[0003] Getter is a necessary material to ensure the normal operation of the pixel-level packaging structure of the uncooled infrared detector. In the pixel-level packaging structure, the getter layer is generally arranged on the upper surface of the integrated circuit substrate and corresponds to the infrared sensor unit, that is, the getter layer is located below the microbolometer. The surface of the getter layer presents a cracked and uneven structure, which will reduce the reflectivity of the getter layer. The better the getter performance, the more obvious the cracked and uneven structure on the surface. Therefore, the getter layer will have an absorption effect on infrared radiation, reduce the reflection of infrared radiation, and then affect the absorption of infrared radiation by the infrared sensor unit, thereby affecting the performance of the pixel-level packaging structure of the uncooled infrared detector; due to the characteristics of the pixel-level packaging process, the getter layer arranged in the pixel cavity must resist the influence of oxidation during the release of organic glue. The release of organic glue will reduce the reflectivity of the getter and affect the detection accuracy of the infrared detector.

[0004] Therefore, how to solve the above technical problems should be the focus of those skilled in the art. Summary of the Invention

[0005] The purpose of this application is to provide a pixel-level packaging structure of an uncooled infrared detector and a manufacturing method thereof, so as to improve the performance of the pixel-level packaging structure of the uncooled infrared detector.

[0006] To solve the above technical problems, the present application provides a pixel-level packaging structure of an uncooled infrared detector, comprising:

[0007] An integrated circuit substrate and a pixel device provided on an upper surface of the integrated circuit substrate;

[0008] The pixel device includes a pixel unit and an air-getter unit provided on one side of the pixel unit, wherein the air-getter unit includes a getter layer provided on the upper surface of the integrated circuit substrate, a support layer, and a sealing layer provided on the upper surface of the support layer; a cavity in the air-getter unit is in communication with a cavity in the pixel unit;

[0009] Alternatively, the pixel device includes a getter layer and a reflective layer provided on the upper surface of the integrated circuit substrate, and an infrared sensor unit provided above the reflective layer and corresponding to the reflective layer.

[0010] Optionally, also include:

[0011] An anti-reflection layer is provided on the upper surface of the sealing layer.

[0012] Optionally, the material of the anti-reflection layer is zinc sulfide or germanium.

[0013] Optionally, the support layer has a thickness between 750 nm and 1250 nm, including the end points.

[0014] Optionally, the sealing layer is made of germanium or zinc sulfide.

[0015] Optionally, the thickness of the reflective layer is Endpoint values ​​are included.

[0016] Optionally, the thickness of the getter layer is Endpoint values ​​are included.

[0017] The present application also provides a method for manufacturing a pixel-level packaging structure of an uncooled infrared detector, comprising:

[0018] preparing an integrated circuit substrate;

[0019] forming a pixel device on the upper surface of the integrated circuit substrate;

[0020] The pixel device includes a pixel unit and an air-intake unit provided on one side of the pixel unit, the air-intake unit includes an air-intake agent layer provided on the upper surface of the integrated circuit substrate, a support layer, and a sealing layer provided on the upper surface of the support layer; the cavity in the air-intake unit is connected to the cavity of the pixel unit; or the pixel device includes a air-intake agent layer and a reflective layer provided on the upper surface of the integrated circuit substrate, and an infrared sensor unit provided above the reflective layer and corresponding to the reflective layer.

[0021] Optionally, when the pixel device includes a getter layer and a reflective layer provided on the upper surface of the integrated circuit substrate, and an infrared sensor unit provided above and corresponding to the reflective layer, forming the pixel device on the upper surface of the integrated circuit substrate includes:

[0022] Depositing a reflective layer to be processed on the upper surface of the integrated circuit substrate, and patterning the reflective layer to be processed to form a reflective layer;

[0023] Depositing a getter layer to be processed on the upper surface of the integrated circuit substrate, and patterning the getter layer to be processed to form a getter layer;

[0024] forming a first sacrificial layer on an area of ​​the upper surface of the integrated circuit substrate not covered by the getter layer and the reflective layer and on an upper surface of the getter layer and the reflective layer;

[0025] Etching the first sacrificial layer to form a groove, and forming an electrode connecting column in the groove;

[0026] forming an infrared sensor unit on the upper surface of the first sacrificial layer at a position corresponding to the reflective layer;

[0027] forming a second sacrificial layer on an area of ​​the upper surface of the first sacrificial layer not covered by the infrared sensing unit and on an upper surface of the infrared sensing unit;

[0028] Etching the first sacrificial layer and the second sacrificial layer to form a supporting groove; wherein the etching is performed in two steps, the first step is to etch to a depth reaching the upper surface of the inter-pixel channel, and the second step is to etch in the non-inter-pixel channel area to a depth reaching the upper surface of the integrated circuit substrate;

[0029] forming a supporting layer in the supporting groove, and etching the supporting layer to form a release hole;

[0030] releasing the first sacrificial layer and the second sacrificial layer through the release hole;

[0031] A sealing layer is formed on the upper surface of the supporting layer, and the sealing layer fills the release hole.

[0032] Optionally, after forming the sealing layer on the upper surface of the supporting layer, the method further comprises:

[0033] An anti-reflection layer is formed on the upper surface of the sealing layer.

[0034] The present application provides a pixel-level packaging structure of an uncooled infrared detector, comprising: an integrated circuit substrate and a pixel device arranged on the upper surface of the integrated circuit substrate; the pixel device comprises a pixel unit and an air intake unit arranged on one side of the pixel unit, the air intake unit comprising a getter layer arranged on the upper surface of the integrated circuit substrate, a support layer, and a sealing layer arranged on the upper surface of the support layer; the cavity in the air intake unit is connected to the cavity of the pixel unit; or the pixel device comprises a getter layer and a reflective layer arranged on the upper surface of the integrated circuit substrate, and an infrared sensor unit arranged above the reflective layer and corresponding to the reflective layer.

[0035] It can be seen that the pixel-level packaging structure in the present application includes an integrated circuit substrate and a pixel device provided on the upper surface of the integrated circuit substrate. The pixel device includes two structures. One pixel device includes a pixel unit and a getter unit provided on one side of the pixel unit. The getter unit includes a getter layer, a support layer, and a sealing layer. The cavity in the getter unit is connected to the cavity of the pixel unit. That is, the getter layer is not provided in the pixel unit. While achieving the getter performance, it does not absorb infrared radiation, that is, it does not affect the pixel unit, thereby improving the performance of the pixel-level packaging structure. The other pixel device includes a getter layer and a reflective layer, and an infrared sensor unit provided above and corresponding to the reflective layer. That is, the getter layer does not correspond to the infrared sensor unit and does not affect the infrared sensor unit's absorption of infrared radiation, thereby improving the performance of the pixel-level packaging structure. Moreover, since it is the reflective layer, not the getter layer, that corresponds to the infrared sensor unit, when the getter layer is affected by oxidation and the reflectivity is reduced, or when the surface structure is significantly uneven and causes the reflectivity to be reduced, it does not affect the infrared sensor unit, thereby improving the accuracy of the pixel-level packaging structure.

[0036] In addition, the present application also provides a method for manufacturing a pixel-level packaging structure of an uncooled infrared detector having the above advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present application or the technical solutions of the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0038] Figure 1 A schematic diagram of a pixel-level packaging structure of an uncooled infrared detector provided in an embodiment of the present application;

[0039] Figure 2 for Figure 1 A top view of a pixel-level packaging structure of an uncooled infrared detector is shown;

[0040] Figure 3 for Figure 4 A schematic structural diagram of a pixel unit array in a pixel-level packaging structure of another uncooled infrared detector is shown;

[0041] Figure 4 A top view of a pixel-level packaging structure of another uncooled infrared detector provided in an embodiment of the present application;

[0042] Figure 5 for Figure 4 A schematic structural diagram of an air intake unit in a pixel-level packaging structure of another uncooled infrared detector is shown;

[0043] Figure 6 A flowchart of a method for manufacturing a pixel-level packaging structure of an uncooled infrared detector provided in an embodiment of the present application;

[0044] Figures 7 to 16 for Figure 2 Process flow chart of the BB cross-section of the pixel-level packaging structure of the central African cooled infrared detector. DETAILED DESCRIPTION

[0045] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific embodiments. Obviously, the embodiments described are only a part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making any creative efforts are within the scope of protection of the present application.

[0046] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0047] As described in the background technology section, currently in the pixel-level packaging structure, the getter layer corresponds to the infrared sensor unit, and the getter layer will have an absorption effect on infrared radiation, affecting the absorption of infrared radiation by the infrared sensor unit, thereby affecting the performance of the pixel-level packaging structure of the uncooled infrared detector; in addition, due to the characteristics of the pixel-level packaging process, the getter layer arranged in the pixel cavity must resist the influence of oxidation during the release of the organic glue; the cracked and uneven structure on the surface of the getter layer will reduce the reflectivity of the getter layer. The better the air absorption performance, the more obvious the cracked and uneven structure on the surface. The release process of the organic glue will reduce the reflectivity of the getter. Taking zirconium-based and titanium-based getters as examples, the release process will reduce the reflectivity of the getter by about 10%, affecting the detection accuracy of the infrared detector.

[0048] In view of this, this application provides a pixel-level packaging structure of an uncooled infrared detector, please refer to Figures 1 to 4 ,include:

[0049] An integrated circuit substrate 1 and a pixel device provided on the upper surface of the integrated circuit substrate 1;

[0050] The pixel device includes a pixel unit and an air-getter unit provided on one side of the pixel unit. The air-getter unit includes a getter layer 2 provided on the upper surface of the integrated circuit substrate 1, a support layer 8, and a sealing layer 10 provided on the upper surface of the support layer 8. The cavity in the air-getter unit is connected to the cavity of the pixel unit.

[0051] Alternatively, the pixel device includes a getter layer 2 and a reflective layer 3 provided on the upper surface of the integrated circuit substrate 1 , and an infrared sensor unit 5 provided above the reflective layer 3 and corresponding to the reflective layer 3 .

[0052] The integrated circuit substrate 1 is a CMOS integrated circuit substrate 1 .

[0053] The two structures of pixel devices are introduced below.

[0054] for Figure 1 and Figure 2 The pixel-level packaging structure of the uncooled infrared detector shown in the figure includes a getter layer 2 and a reflective layer 3 provided on the upper surface of an integrated circuit substrate 1, and an infrared sensor unit 5 provided above and corresponding to the reflective layer 3. The infrared sensor unit 5 includes a thermosensitive film that can convert thermal signals into electrical signals. The film can be made of vanadium oxide, amorphous silicon, titanium oxide, etc.

[0055] It should be noted that the pixel device further includes an electrode connection column 12 provided on the upper surface of the integrated circuit substrate 1, a support layer 8, and a sealing layer 10 provided on the upper surface of the support layer 8. The specific configuration of the electrode connection column 12, the support layer 8, and the sealing layer 10 can be referred to in related art.

[0056] The thickness of the support layer 8 may be between 750 nm and 1250 nm, inclusive, and the material of the support layer 8 may be α-Si.

[0057] During the fabrication process, release holes 9 are formed in the support layer 8 to release the sacrificial material. It should be noted that these release holes 9 are filled with a sealing layer 10, sealing the package structure. A pixel device includes one or more release holes 9, typically with a width of 200 nm to 500 nm.

[0058] The pixel devices are interconnected, and the getter layer 2 is set at the gap between the pixel devices. Figure 1 The number of pixel devices shown in FIG is two.

[0059] The material of the getter layer 2 includes but is not limited to low-temperature activated materials with zirconium and titanium as main components, and getters with strong gettering performance. The shape of the getter layer 2 can be made into a regular shape or an irregular shape, and the size of the getter layer 2 depends on the pixel device.

[0060] In order to ensure the getter performance, save getter materials and control the production cost, the thickness of the getter layer 2 can be Include endpoint values, e.g. wait.

[0061] The material of the reflective layer 3 is metal, and the specific material can be selected by oneself, and this application does not limit it. The thickness of the reflective layer 3 can be Include endpoint values, e.g. wait.

[0062] Furthermore, in order to increase the transmittance of infrared radiation and improve the performance of the pixel-level packaging structure of the uncooled infrared detector, the pixel-level packaging structure of the uncooled infrared detector also includes:

[0063] The anti-reflection layer 11 is provided on the upper surface of the sealing layer 10 .

[0064] It should be noted that the material of the anti-reflection layer 11 is not limited in this application and can be set at will. For example, the material of the anti-reflection layer 11 is germanium, or the material of the anti-reflection layer 11 is zinc sulfide.

[0065] It should also be noted that the material of the sealing layer 10 is not specifically limited in this application and can be set at will. For example, the material of the sealing layer 10 is zinc sulfide, or the material of the sealing layer 10 is germanium, etc.

[0066] The thickness of the sealing layer 10 is generally between 100 nm and 3000 nm, and the thickness of the anti-reflection layer 11 is generally between 100 nm and 3000 nm.

[0067] In this embodiment, the pixel device includes a getter layer 2 and a reflective layer 3, and an infrared sensor unit 5 is arranged above the reflective layer 3 and corresponding to the reflective layer 3. That is, the getter layer 2 does not correspond to the infrared sensor unit 5, and will not affect the infrared sensor unit 5's absorption of infrared radiation, thereby improving the performance of the pixel-level packaging structure. Moreover, since it is the reflective layer 3, not the getter layer 2, that corresponds to the infrared sensor unit 5, when the getter layer 2 is affected by oxidation and the reflectivity is reduced, and when the surface has an obviously uneven structure that causes the reflectivity to be reduced, it will not affect the infrared sensor unit 5, thereby improving the accuracy of the pixel-level packaging structure.

[0068] for Figure 4 The pixel-level packaging structure of the uncooled infrared detector shown in the figure comprises a pixel unit 13 and an air-intake unit 14 provided on one side of the pixel unit. The air-intake unit 14 comprises a getter layer 2 provided on the upper surface of an integrated circuit substrate 1, a support layer 8, and a sealing layer 10 provided on the upper surface of the support layer 8. The cavity in the air-intake unit is connected to the cavity of the pixel unit.

[0069] Figure 3 This is a schematic diagram of the structure of a pixel unit 13 array in this embodiment. Pixel unit 13 includes a reflective layer 3 and electrode connection pillars 12 disposed on the upper surface of an integrated circuit substrate 1, a support layer 8, an infrared sensor unit 5 disposed above and corresponding to the reflective layer 3, and a sealing layer 10 disposed on the upper surface of the support layer 8. The release holes 9 in the support layer 8 are filled with the sealing layer 10. The infrared sensor unit 5 includes a thermosensitive film that converts thermal signals into electrical signals. The film can be made of vanadium oxide, amorphous silicon, titanium oxide, or the like. Pixel unit 13 does not include a getter layer 2.

[0070] The material of the reflective layer 3 is metal, and the specific material can be selected and is not limited in this application. The thickness of the reflective layer 3 can be Include endpoint values, e.g. wait.

[0071] The structural diagram of the air suction unit 14 in this embodiment is as follows Figure 5 As shown, the getter unit includes a getter layer 2 disposed on the upper surface of an integrated circuit substrate 1, a support layer 8, and a sealing layer 10 disposed on the upper surface of the support layer 8. The cavity within the getter unit communicates with the cavity of the pixel unit. During the manufacturing process, a release hole 9 is formed in the support layer 8 to release the sacrificial material. It should be noted that the release hole 9 is filled with the sealing layer 10, making the package structure sealed.

[0072] The getter layer 2 is provided in the getter unit without the infrared sensor unit 5 , and the getter unit and the pixel unit are communicated with each other.

[0073] In order to ensure the getter performance, save getter materials and control the production cost, the thickness of the getter layer 2 can be Include endpoint values, e.g. The materials of the getter layer 2 include, but are not limited to, low-temperature activated materials with zirconium or titanium as main components and materials with strong gettering properties.

[0074] The thickness of the support layer 8 can be between 750 nm and 1250 nm, inclusive. The material of the support layer 8 can be α-Si. Each pixel unit and each getter unit includes two release holes 9, and the width of the release holes 9 is generally between 200 nm and 500 nm.

[0075] In order to increase the transmittance of infrared radiation and improve the performance of the pixel-level packaging structure of the uncooled infrared detector, the pixel-level packaging structure of the uncooled infrared detector also includes:

[0076] The anti-reflection layer 11 is provided on the upper surface of the sealing layer 10 .

[0077] It should be noted that the material of the anti-reflection layer 11 is not limited in this application and can be selected at will. For example, the material of the anti-reflection layer 11 can be germanium, or zinc sulfide, etc. When the sealing layer is made of germanium, the material of the anti-reflection layer can be zinc sulfide; when the sealing layer is made of zinc sulfide, the material of the anti-reflection layer can be germanium.

[0078] It should also be noted that the material of the sealing layer 10 is not specifically limited in this application and can be set at will. For example, the material of the sealing layer 10 is zinc sulfide, or the material of the sealing layer 10 is germanium.

[0079] In this embodiment, the pixel device includes a pixel unit and an air-intake unit arranged on one side of the pixel unit. The air-intake unit includes an air-intake agent layer 2, a support layer 8, and a sealing layer 10. The cavity in the air-intake unit is connected to the cavity of the pixel unit, that is, the air-intake agent layer 2 is not arranged in the pixel unit. While achieving the air-intake performance, it does not have an absorption effect on infrared radiation, that is, it does not affect the pixel unit, thereby improving the performance of the pixel-level packaging structure and improving the accuracy of the pixel-level packaging structure.

[0080] It should be emphasized that vacuum failure in a single pixel device will cause failure of the entire pixel-level packaging junction. In this application, based on the literature "Latest improvements in microbolometer thin film packaging", researchers from the Atomic Energy and Alternative Energies Commission in 2014 adjusted the coating materials, processes and coating parameters to ensure that there are no pixel blind pixels caused by vacuum failure.

[0081] The present application also provides a flowchart of a method for manufacturing a pixel-level packaging structure of an uncooled infrared detector, including:

[0082] Step S101: prepare an integrated circuit substrate.

[0083] The integrated circuit substrate is a CMOS integrated circuit substrate.

[0084] Step S102: forming pixel devices on the upper surface of the integrated circuit substrate;

[0085] The pixel device includes a pixel unit and an air-intake unit provided on one side of the pixel unit, the air-intake unit includes an air-intake agent layer provided on the upper surface of the integrated circuit substrate, a support layer, and a sealing layer provided on the upper surface of the support layer; the cavity in the air-intake unit is connected to the cavity of the pixel unit; or the pixel device includes a air-intake agent layer and a reflective layer provided on the upper surface of the integrated circuit substrate, and an infrared sensor unit provided above the reflective layer and corresponding to the reflective layer.

[0086] When the pixel device includes a getter layer and a reflective layer provided on the upper surface of the integrated circuit substrate, and an infrared sensor unit provided above the reflective layer and corresponding to the reflective layer, please refer to Figure 6 , Figure 6 A flowchart of a method for manufacturing a pixel-level packaging structure of an uncooled infrared detector provided in an embodiment of the present application includes:

[0087] Step S201: Prepare an integrated circuit substrate.

[0088] Step S202: depositing a reflective layer to be processed on the upper surface of the integrated circuit substrate, and patterning the reflective layer to be processed to form a reflective layer.

[0089] Step S203: depositing a getter layer to be processed on the upper surface of the integrated circuit substrate, and patterning the getter layer to be processed to form a getter layer.

[0090] For this step, please refer to Figure 7 , the getter layer 2 and the reflective layer 3 are located on the upper surface of the integrated circuit substrate 1. The thickness of the getter layer 2 can be Including the end value. The thickness of the reflective layer 3 can be Endpoint values ​​are included.

[0091] Step S204 : forming a first sacrificial layer on the upper surface of the integrated circuit substrate in the area not covered by the getter layer and the reflective layer and on the upper surfaces of the getter layer and the reflective layer.

[0092] For this step, please refer to Figure 8 The first sacrificial layer 4 covers the getter layer 2 , the reflective layer 3 and the area of ​​the upper surface of the integrated circuit substrate 1 not covered by the getter layer 2 and the reflective layer 3 .

[0093] The first sacrificial layer 4 is an organic sacrificial layer. The material of the first sacrificial layer 4 can be polyimide or amorphous carbon. The thickness of the first sacrificial layer 4 is between 1.5 μm and 2.5 μm.

[0094] Step S205: etching the first sacrificial layer to form a groove, and forming an electrode connecting column in the groove.

[0095] Step S206 : forming an infrared sensor unit on the upper surface of the first sacrificial layer at a position corresponding to the reflective layer.

[0096] For this step, please refer to Figure 9 The infrared sensor unit 5 is located on the upper surface of the first sacrificial layer 4. The infrared sensor unit 5 includes a thermosensitive film that can convert thermal signals into electrical signals. The film can be made of vanadium oxide, amorphous silicon, titanium oxide, etc.

[0097] Step S207 : forming a second sacrificial layer on the area of ​​the upper surface of the first sacrificial layer not covered by the infrared sensing unit and on the upper surface of the infrared sensing unit.

[0098] Please refer to Figure 10 The second sacrificial layer 6 covers the infrared sensor unit 5 and the first sacrificial layer 4. The material of the second sacrificial layer 6 can be SiO2, SiN, etc. The thickness of the second sacrificial layer 6 is between 1.0 μm and 2 μm.

[0099] Step S208: etching the first sacrificial layer and the second sacrificial layer to form a supporting groove; wherein, the etching is performed in two steps, the first step is to etch to a depth to the upper surface of the inter-pixel channel, and the second step is to etch in the non-inter-pixel channel area to a depth to the upper surface of the integrated circuit substrate.

[0100] Please refer to Figure 11 After etching, a support groove 7 is formed, and the function of the support groove 7 is to form a support layer.

[0101] The etching is carried out in two steps. The first step is to etch to the upper surface of the channel between pixels. The etching depth of the first step is D1. The second step is to etch to the integrated circuit substrate in the non-channel area between pixels. The etching depth is D2. Figure 12 As shown, Figure 12 for Figure 1 Schematic diagram of the AA section, Figure 12 The two pixels on the left and right of the dotted line are shown in the figure. The length of half the getter layer is X1, the length of half the inter-pixel channel is X2, the height of the inter-pixel channel is Y1, and the thickness of the getter layer is Y2. X2 is 1.5 to 3 times X1, and Y1 is 1.5 to 3 times Y2.

[0102] Step S209: forming a support layer in the support groove, and etching the support layer to form a release hole.

[0103] For this step, please refer to Figure 13 The thickness of the support layer 8 can be between 750 nm and 1250 nm, including the end value, and the material of the support layer can be α-Si; two release holes 9 are etched on the top of the support layer 8 for each pixel device, such as Figure 14 As shown, the release hole width is 200nm to 500nm.

[0104] It should be pointed out that support layer material is also deposited in the support groove 7 and belongs to the support layer.

[0105] Step S210 : releasing the first sacrificial layer and the second sacrificial layer through the release hole.

[0106] Release the first sacrificial layer and the second sacrificial layer, such as Figure 15 shown.

[0107] Step S211: forming a sealing layer on the upper surface of the supporting layer, wherein the sealing layer fills the release hole.

[0108] For this step, please refer to Figure 16 The thickness of the sealing layer 10 is generally between 100 nm and 3000 nm, and the material of the sealing layer 10 can be zinc sulfide or germanium.

[0109] It should be pointed out that Figures 6 to 16 for Figure 2 In the process flow diagram of the BB section, the electrode connection column does not exist in the BB section.

[0110] In the pixel-level packaging structure of the uncooled infrared detector prepared in this embodiment, the pixel device includes a getter layer and a reflective layer, and an infrared sensor unit is arranged above the reflective layer and corresponding to the reflective layer, that is, the getter layer does not correspond to the infrared sensor unit, and will not affect the infrared sensor unit's absorption of infrared radiation, thereby improving the performance of the pixel-level packaging structure. Moreover, since it is the reflective layer, not the getter layer, that corresponds to the infrared sensor unit, when the getter layer is affected by oxidation and the reflectivity is reduced, and when the surface has an obviously uneven structure that causes the reflectivity to be reduced, it will not affect the infrared sensor unit, thereby improving the accuracy of the pixel-level packaging structure.

[0111] Furthermore, in one embodiment of the present application, after forming the sealing layer on the upper surface of the support layer, the method further comprises:

[0112] An anti-reflection layer is formed on the upper surface of the sealing layer.

[0113] The material of the anti-reflection layer is germanium or zinc sulfide, and the thickness of the anti-reflection layer is generally between 100nm and 3000nm.

[0114] In this embodiment, by providing an anti-reflection layer, the transmittance of infrared radiation can be increased, thereby improving the performance of the pixel-level packaging structure of the uncooled infrared detector.

[0115] When the pixel device includes a pixel unit and an air-getter unit provided on one side of the pixel unit, the air-getter unit includes an air-getter layer provided on the upper surface of the integrated circuit substrate, a support layer, and a sealing layer provided on the upper surface of the support layer; and the cavity in the air-getter unit is connected to the cavity in the pixel unit, the method for manufacturing the pixel-level packaging structure of the uncooled infrared detector is similar to the process of steps S201 to S210 above, except that the presence and position of the reflective layer and the air-getter layer in the pixel unit and the air-getter unit are determined according to the embodiment of the present invention. Figure 3 and Figure 5 The structural diagram shown in the figure can be adjusted, and the preparation process will not be elaborated in detail in this application.

[0116] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from the other embodiments. Reference can be made to the descriptions of the identical or similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and the relevant parts can be referred to the descriptions of the methods.

[0117] The above is a detailed introduction to the pixel-level packaging structure of the uncooled infrared detector provided by the present application and its manufacturing method. This article uses specific examples to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A pixel-level packaging structure of an uncooled infrared detector, characterized in that: include: An integrated circuit substrate and a pixel device provided on an upper surface of the integrated circuit substrate; The pixel device includes a getter layer and a reflective layer provided on the upper surface of the integrated circuit substrate, and an infrared sensor unit provided above and corresponding to the reflective layer; wherein the getter layer is provided in a gap position at a corner of each pixel device; The pixel device further includes a support layer, wherein the support layer corresponding to the support layer located above the getter layer further includes an extension portion extending toward the getter layer, and a gap is formed between the getter layer and the extension portion of the support layer; The pixel device further includes a sealing layer disposed on the upper surface of the supporting layer.

2. The pixel-level packaging structure of the uncooled infrared detector according to claim 1, characterized in that: Also includes: An anti-reflection layer is provided on the upper surface of the sealing layer.

3. The pixel-level packaging structure of the uncooled infrared detector according to claim 2, characterized in that: The material of the anti-reflection layer is zinc sulfide or germanium.

4. The pixel-level packaging structure of the uncooled infrared detector according to claim 1, wherein: The thickness of the support layer is between 750 nm and 1250 nm, including the end points.

5. The pixel-level packaging structure of the uncooled infrared detector according to claim 1, wherein: The sealing layer is made of germanium or zinc sulfide.

6. The pixel-level packaging structure of the uncooled infrared detector according to claim 1, wherein: The thickness of the reflective layer is between 300Å and 2000Å, including end points.

7. The pixel-level packaging structure of an uncooled infrared detector according to any one of claims 1 to 6, characterized in that: The getter layer has a thickness of 3000Å ​​to 7500Å, including end points.

8. A method for manufacturing a pixel-level packaging structure of an uncooled infrared detector, characterized in that: include: preparing an integrated circuit substrate; forming a pixel device on the upper surface of the integrated circuit substrate; The pixel device includes a getter layer and a reflective layer provided on the upper surface of the integrated circuit substrate, and an infrared sensor unit provided above the reflective layer and corresponding to the reflective layer; the getter layer is provided in a gap position at a corner of each of the pixel devices; the pixel device also includes a support layer, and the support layer corresponding to the support layer located above the getter layer also includes an extension portion extending toward the getter layer, and a gap exists between the getter layer and the extension portion of the support layer.

9. The method for manufacturing a pixel-level packaging structure of an uncooled infrared detector according to claim 8, wherein: When the pixel device includes a getter layer and a reflective layer provided on the upper surface of the integrated circuit substrate, and an infrared sensor unit provided above the reflective layer and corresponding to the reflective layer, forming the pixel device on the upper surface of the integrated circuit substrate includes: Depositing a reflective layer to be processed on the upper surface of the integrated circuit substrate, and patterning the reflective layer to be processed to form a reflective layer; Depositing a getter layer to be processed on the upper surface of the integrated circuit substrate, and patterning the getter layer to be processed to form a getter layer; forming a first sacrificial layer on an area of ​​the upper surface of the integrated circuit substrate not covered by the getter layer and the reflective layer and on an upper surface of the getter layer and the reflective layer; Etching the first sacrificial layer to form a groove, and forming an electrode connecting column in the groove; forming an infrared sensor unit on the upper surface of the first sacrificial layer at a position corresponding to the reflective layer; forming a second sacrificial layer on an area of ​​the upper surface of the first sacrificial layer not covered by the infrared sensor unit and on an upper surface of the infrared sensor unit; Etching the first sacrificial layer and the second sacrificial layer to form a supporting groove; wherein the etching is performed in two steps, the first step is to etch to a depth reaching the upper surface of the inter-pixel channel, and the second step is to etch in the non-inter-pixel channel area to a depth reaching the upper surface of the integrated circuit substrate; forming a supporting layer in the supporting groove, and etching the supporting layer to form a release hole; releasing the first sacrificial layer and the second sacrificial layer through the release hole; A sealing layer is formed on the upper surface of the supporting layer, and the sealing layer fills the release hole.

10. The method for manufacturing a pixel-level packaging structure of an uncooled infrared detector according to claim 9, wherein: After forming the sealing layer on the upper surface of the supporting layer, the method further comprises: An anti-reflection layer is formed on the upper surface of the sealing layer.

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