Area array level packaging uncooled infrared detector and preparation method thereof

Abstract

The invention discloses an area array level packaging uncooled infrared detector and a preparation method thereof, the detector comprises a substrate, an effective element array and a getter, the substrate is provided with an effective element area and a non-effective element area, and the effective element array is arranged in the effective element area; and the getter is suspended in the non-effective element area, and the position of the getter is higher than that of the effective element array. According to the invention, the getter is hung upside down, so that the influence of the temperature on the getter in the preparation process in the prior art can be avoided, the problem that the getter fails in the implementation process in the prior art is effectively solved, and the vacuum environment in the packaging structure is effectively maintained.

Description

An array-level packaged uncooled infrared detector and its preparation method Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to an area array-level packaged uncooled infrared detector and a preparation method thereof. Background Art

[0002] Uncooled infrared detectors perform imaging in an ultra-high vacuum environment by absorbing external infrared energy and converting it into electrical signals. During the production of uncooled infrared detectors, a getter must be used and activated within the detector's vacuum-sealed environment to remove residual gas and maintain a higher vacuum level. Furthermore, if the vacuum level drops during later use, the getter can be reactivated to absorb the residual gas, restoring the detector's high vacuum.

[0003] Currently, the packaging methods of uncooled infrared detectors mainly include metal, ceramic, wafer-level and array-level packaging. Among them, metal and ceramic packaging use columnar getters, which are welded to the tube shell leads, and electrically activated or thermally activated getters are used before packaging to maintain high vacuum.

[0004] Wafer-level packaging uses thin film getters, which are integrated into the cap wafer. Finally, the high temperature of bonding is used to activate the getters by thermal activation during bonding. This can avoid the influence of temperature on the getters during the MEMS process preparation of the chip.

[0005] Area array level packaging integrates the cap wafer and the MEMS wafer on the basis of wafer level packaging, and uses one material to directly encapsulate the entire surface of the MEMS microstructure. Thermal activation is to heat up the entire chip. However, the thermosensitive material of the uncooled infrared detector chip is not resistant to high temperature. When the temperature exceeds a certain range, it will cause the metal to lose its activity. Therefore, the temperature of the getter thermal activation is limited to not being too high. However, the getter thermal activation requires a high temperature environment. Low temperature will lead to insufficient activation of the getter, which is not conducive to maintaining the vacuum degree.

[0006] At the same time, the multiple high-temperature baking and organic solution cleaning processes involved in the normal semiconductor process flow can affect the performance of the getter and may even activate the getter prematurely. Therefore, it is necessary to redesign the structure and preparation method of the getter so that the temperature at which the getter is activated does not inactivate the heat-sensitive material, while also allowing the getter to be integrated into the chip wafer.

[0007] Summary of the Invention

[0008] The purpose of the present invention is to provide an array-level packaged non-cooled infrared detector and a preparation method thereof. By adopting an inverted getter method, the influence of temperature on the getter during the preparation process under the existing process can be avoided, the problem of getter failure caused by the existing process during implementation can be effectively solved, and the vacuum environment inside the packaging structure can be effectively maintained.

[0009] According to a first aspect of the present invention, an area array-level packaged uncooled infrared detector is proposed, comprising a substrate, an effective element array, and a getter, wherein the substrate has an effective element region and an ineffective element region, and the effective element array is arranged in the effective element region; the getter is suspended in the ineffective element region, and the position of the getter is higher than the effective element array.

[0010] Furthermore, the non-effective element region includes a blind element region, the blind element array is arranged in the blind element region, and the getter is suspended above the blind element array.

[0011] Furthermore, it also includes a packaging cap, which is packaged on the substrate to form a sealed cavity; the effective element array and the getter are both in the sealed cavity, and the getter is upside down on the inner side of the packaging cap.

[0012] Furthermore, the packaging cap includes a structural cavity and an infrared film, the infrared film is located on the outside of the structural cavity, and the getter is upside down and arranged on the inside of the structural cavity.

[0013] Furthermore, a release hole for releasing the sacrificial layer is provided on the structural cavity; and a through hole is provided on the getter corresponding to the release hole above the ineffective element area.

[0014] Furthermore, a support structure is provided above the ineffective element region, and the getter is supported above the support structure and / or the getter is hung upside down below the support structure.

[0015] Furthermore, the getter is continuously disposed over the inactive element region.

[0016] Furthermore, a protective film layer is provided on the surface of the getter.

[0017] Furthermore, the protective film layer is made of a material that clusters above 300 degrees Celsius and does not react directly with oxygen.

[0018] Preferably, the material of the protective film layer is Au (gold), and the final shape can be gold foil.

[0019] According to a second aspect of the present invention, a method for preparing an area array-level packaged uncooled infrared detector is provided, which is used to prepare the area array-level packaged uncooled infrared detector proposed in the first aspect. The preparation scheme specifically includes:

[0020] S1. Prepare or provide a substrate;

[0021] S2, dividing the substrate into an effective element region and an ineffective element region, and manufacturing an effective element array in the effective element region;

[0022] S3, making a suspended getter in the non-effective element area;

[0023] S4, making a packaging cap covering the substrate.

[0024] The getter is connected to the bottom of the packaging cap.

[0025] Furthermore, the step S3 specifically includes:

[0026] S311, making a sacrificial layer on the structure made in step S2;

[0027] S321, depositing a getter material on the sacrificial layer to form a whole getter;

[0028] After step S4, the method further includes:

[0029] The sacrificial layer is released, so that the entire getter formed in step S321 is hung upside down below the package cap, and the position of the getter is higher than the effective cell array.

[0030] Furthermore, the step S321 specifically includes:

[0031] First, a protective film layer material is deposited on the sacrificial layer to form a protective film layer; then, a getter material is deposited on the protective film layer to form a whole piece of getter.

[0032] Furthermore, the step S3 specifically includes:

[0033] S312, manufacturing a support structure in the non-active element area above the substrate;

[0034] S322 , depositing a getter material on the surface of the support structure to form a whole piece of getter.

[0035] Furthermore, the method further includes using a high-temperature thermal activation method to cluster the protective film layer so as to expose the getter, thereby activating the getter.

[0036] The beneficial effects of the present invention are:

[0037] The present invention provides an area array-level packaged uncooled infrared detector and a preparation method thereof. Different from the existing process flow, a getter is suspended above the non-effective element area, so that the preparation process of the getter is placed after the preparation process of the effective element array, avoiding the influence of the preparation process of the effective element array on the getter, such as activating the getter in advance, effectively solving the problem of easy failure of the getter during the preparation process in the area array-level package.

[0038] The present invention hangs the getter upside down on the packaging cap, optimizing the process flow. On the one hand, the getter preparation process is designed at the last stage of the entire MEMS process, avoiding the influence of various previous processes on the getter. On the other hand, the getter is integrated with the packaging cap, further simplifying the structure and process.

[0039] The present invention combines the getter protection process and integrates a specific protective film layer into the getter preparation process, thereby avoiding the problem of the getter being activated in advance during the manufacturing process.

[0040] The present invention designs a new layout, setting the getter above the ineffective element area, separating the getter activation area from the effective element imaging area, and the getter is deposited on the entire surface of the activation area, which increases the amount of getter, can effectively improve the getter performance, and maintain the high vacuum effect of the cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings, which are incorporated into and constitute a part of the specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the present invention. In the drawings, similar reference numerals are used to represent similar elements. The drawings described below are some embodiments of the present invention, but not all. It is clear that those skilled in the art can derive other drawings from these drawings without inventive effort.

[0042] FIG1 is a structural diagram of an area array-level packaged uncooled infrared detector according to an embodiment of the present invention;

[0043] FIG2 is a schematic diagram of providing a sacrificial layer in a method for preparing an area array-level packaged uncooled infrared detector according to an embodiment of the present invention;

[0044] FIG3 is a schematic diagram of a method for preparing an area array-level packaged uncooled infrared detector after secondary spin coating of a sacrificial layer according to an embodiment of the present invention;

[0045] FIG4 is a schematic diagram of designing a photoresist in a method for preparing an area array-level packaged uncooled infrared detector according to an embodiment of the present invention;

[0046] FIG5 is a schematic diagram of depositing a protective film layer and a getter in a method for preparing an area array-level packaged uncooled infrared detector according to an embodiment of the present invention;

[0047] FIG6 is a schematic diagram of a method for preparing an area array-level packaged uncooled infrared detector according to an embodiment of the present invention after stripping the photoresist;

[0048] FIG7 is a schematic diagram of a packaging structure cavity in a method for preparing an area array-level packaged uncooled infrared detector according to an embodiment of the present invention;

[0049] FIG8 is a schematic diagram of providing a release hole in a method for preparing an area array-level packaged uncooled infrared detector according to an embodiment of the present invention;

[0050] FIG9 is a schematic diagram of a method for preparing an area array-level packaged uncooled infrared detector after releasing a sacrificial layer according to an embodiment of the present invention;

[0051] FIG10 is a schematic diagram of a method for preparing an area array-level packaged uncooled infrared detector after encapsulating an infrared film according to an embodiment of the present invention;

[0052] FIG11 is a schematic diagram of depositing a getter on a support structure according to an embodiment of the present invention;

[0053] FIG12 is a schematic diagram of depositing a getter under a support structure according to an embodiment of the present invention.

[0054] In the figure: 1. Getter; 2. Protective film layer; 3. Package cap; 31. Structural cavity; 32. Infrared film; 4. Release hole; 5. Sacrificial layer; 51. First layer; 52. Second layer; 6. Effective element array; 7. Blind element array; 8. Substrate; 9. Photoresist.

[0055] Specific implementation method

[0056] To more clearly illustrate the embodiments of the present invention and the technical solutions in the prior art, the specific embodiments of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings and other embodiments based on these drawings without inventive effort. Furthermore, the design orientation only represents the relative positional relationship between the components, not the absolute positional relationship.

[0057] Example 1

[0058] According to a first aspect of the present invention, an area array-level packaged uncooled infrared detector is provided. As shown in FIG1 , the detector comprises a substrate 8, an active element array 6, and a getter 1. The substrate 8 has an active element region and an inactive element region, and the active element array 6 is disposed within the active element region. The getter 1 is suspended from the inactive element region and positioned higher than the active element array 6. The active element array 6 is located on the upper surface of the substrate 8.

[0059] It can be understood that all parts of the substrate 8 except the effective element area are ineffective element areas. The getter is arranged in the ineffective element area and covers part or all of the area of ​​the ineffective area, which can be adjusted according to the actual demand for the getter.

[0060] In an embodiment of the present application, the non-effective element region includes a blind element region, in which a blind element array 7 is provided. The blind element array 7 is located on the upper surface of the substrate 8 , and the getter 1 is suspended above the blind element array 7 .

[0061] In the embodiment of the present application, a packaging cap 3 is further included. The packaging cap 3 is sealed on a substrate 8 to form a sealed cavity. The substrate 8 contains a readout circuit. The space between the packaging cap 3 and the substrate 8 should be vacuum. An active element array 6 and a blind element array 7 are integrated on the substrate 8 on one side of the sealed cavity. The active element array 6 and the blind element array 7 are located in the active element area and the inactive area, respectively, and are separated from each other. A getter 1 is provided upside down on the packaging cap 3 on the other side of the sealed cavity, and the getter 1 is suspended above the blind element array 7.

[0062] Specifically, the packaging cap 3 includes a structural cavity 31 and an infrared film 32 . The infrared film 32 is arranged on the top surface of the structural cavity 31 , and the getter 1 is hung upside down inside the structural cavity 31 .

[0063] It should be noted that the getter 1 is bundled with the package cap 3, which serves as the cover, and is no longer attached to the substrate 8 for preparation. This places the preparation process of the getter 1 after the preparation process of the effective element array 6, preventing the preparation process of the effective element array 6 from affecting the getter, and resolving the problem of getter failure during the preparation process in area array-level packaging. Therefore, the getter 1 in this application is not affected by the high temperatures of the production process of the effective element array 6 on the substrate 8, effectively resolving the problem raised in this application and effectively avoiding the problem of getter failure during the preparation process in area array-level packaging.

[0064] It is understood that the getter 1 is attached to the packaging cap 3. After the packaging cap 3, which serves as the cover, is separated from the substrate 8, the getter 1 is completely unaffected by the manufacturing process of the substrate 8. The substrate 8 can be easily manufactured in a relatively independent process environment, without having to consider the impact of getter 1 failure. Replacement of the getter 1 and reuse of the substrate 8 are no longer restricted.

[0065] In the present application, the upper surface of the substrate 8 is in a sealed cavity, and an effective element array 6 and a blind element array 7 are integrated on the upper surface of the substrate 8, wherein the effective element array 6 is the effective imaging area, and the blind element array 7 is separated from the effective element array 6 and can be used as a reference element to eliminate the influence of substrate temperature and ambient temperature changes on the effective element array 6.

[0066] In one specific embodiment, active element array 6 includes multiple image elements for imaging, each of which is electrically connected to a readout circuit within substrate 8 to achieve imaging. Blind element array 7 includes multiple blind elements, each of which is electrically connected to a readout circuit within substrate 8 and serves as a reference element.

[0067] The readout circuit belonging to the pixel and the readout circuit belonging to the blind pixel can be set independently of each other. Since the blind pixel is not restricted by high temperature, the getter 1 can be thermally activated in the blind pixel array 7 area; in this application, the getter 1 is hung upside down above the blind pixel array 7, which can save the internal space of the chip on the one hand, and facilitate the activation of the getter 1 on the other hand without affecting the effective element array 6.

[0068] In the embodiment of the present application, the getter 1 is placed upside down above the blind element array 7, separated from the active element array 6, and can be activated by thermal activation. During the preparation of the getter 1, if it is necessary to achieve the upside-down configuration of the getter 1, temporary or permanent support is required.

[0069] The figures of this application are shown using a temporary support as an example. As an implementation method for achieving an inverted getter 1, the temporary support can be a sacrificial layer. After the preparation of the getter 1 is completed, the sacrificial layer is released to form an inverted effect. Specifically:

[0070] In order to realize the structural feature of the inverted getter 1, a sacrificial layer 5 can be pre-set to temporarily support the getter 1 to reach the spatial position required for inverted suspension. After the laying of each layer is completed, the sacrificial layer 5 is released to realize the separation and inversion of the getter 1 relative to the substrate 8.

[0071] In a specific embodiment, the substrate 8, sacrificial layer 5, getter 1 space layer, and encapsulation cap 3 space layer can be laid in sequence, with the substrate 8 being located at the bottom layer, the sacrificial layer 5 serving as a temporary structure between the getter 1 and the substrate 8, and the encapsulation cap 3 being located above the getter 1. After the sacrificial layer 5 is released, the structural layer formed by the getter 1 exists in an upside-down manner attached to the structural cavity 31. The getter 1 no longer makes direct contact with the substrate 8 of the substrate. The getter 1 is suspended in an upside-down manner above the substrate 8, that is, it is correspondingly suspended above the blind element array 7, and the position of the getter 1 is higher than the effective element array 6.

[0072] It can be understood that the packaging cap 3, as a packaging structure, has no direct impact on the high temperature during the substrate 8 preparation process, while the getter 1, which is attached to the packaging cap 3 and is set upside down, can effectively avoid the impact of the high temperature during the substrate 8 preparation process and will not be activated or fail prematurely.

[0073] In the embodiments of the present application, a protective film layer 2 can be added between the getter 1 and the sacrificial layer 5 to prevent damage to the structural properties of the getter 1 when the sacrificial layer 5 is released. The protective film layer 2 can separate the sacrificial layer 5 from the structural layers of the getter 1, forming a distinct layered effect, which helps protect the finished getter 1 from damage and the impact of the release of the sacrificial layer 5.

[0074] In a specific embodiment, the protective film layer 2 serves as an isolation film to isolate the sacrificial layer 5 from the getter 1 . When the sacrificial layer 5 is released, the protective film layer 2 can effectively prevent the getter 1 from being extracted and released.

[0075] In the present application, the method adopted for releasing the sacrificial layer 5 is to open a release hole 4 on the structural cavity 31, but this also destroys the sealing properties of the structural cavity 31 itself, so that the structural cavity 31 as part of the cover body no longer has an effective packaging effect and cannot meet the requirement of a sealed cavity.

[0076] Therefore, the present application applies an infrared antireflection film (IR film 32) to the outer surface of the structural cavity 31. This film not only blocks the release hole 4 to achieve the original packaging effect, but also provides infrared antireflection. It can be understood that the IR film 32 compensates for the packaging defects of the release hole 4 provided in the structural cavity 31. The IR film 32 cooperates with the structural cavity 31 to achieve a sealing effect on the substrate 8. After activating the getter 1, a sealed cavity with a high vacuum that meets the requirements can be formed.

[0077] It is understandable that the infrared film 32 should at least cover the area where the release holes 4 are opened on the structural cavity 31, and block all the release holes 4, so as to achieve effective packaging and enable the sealed cavity to have the basic conditions for forming a high vacuum that meets the requirements.

[0078] In a specific embodiment, the release hole 4 can be opened corresponding to the effective element array 6 and the blind element array 7 on the substrate 8. Specifically, a release hole 4 can be opened for each pixel / blind element. As shown in Figure 1, a release hole 4 is opened corresponding to the pixel in the effective element array 6 and a release hole is opened corresponding to the blind element in the blind element array 7.

[0079] It can be understood that the opening position of the release hole 4 includes the inverted area of ​​the getter 1 on the structural cavity 31, and the getter 1 and the protective film layer 2 open through holes corresponding to the release holes 4, so that the release holes 4 opened in the inverted area are connected to the through holes one by one. When the sacrificial layer 5 is released, the multiple release holes 4 opened on the structural cavity 31 can effectively perform their functions.

[0080] It should be noted that the protective film layer 2 has through holes corresponding to the release holes 4 and the getter 1 at the same position. When the protective film layer 2 is formed, a hole is first opened on the getter 1, and then the protective film layer 2 is laid into the inner wall of the hole to reduce the collateral effect of the sacrificial layer 5 on the getter 1 when it is activated and released.

[0081] As another inverted implementation of the getter 1, the permanent support may be a support structure. After the preparation of the getter 1 is completed, the support structure of the getter 1 is not removed, and the support structure presents an inverted effect together with the getter 1. Specifically:

[0082] A support structure may be formed based on the sidewall of the package cap 3 close to the blind element array 7 or the substrate 8 in the non-effective element area, and the getter 1 may be prepared on the support structure.

[0083] In one specific embodiment, a support structure is formed on the sidewall of the package cap 3 near the blind element array 7. This support structure can be a horizontal plate suspended above the blind element array 7. The getter 1 is prepared on the horizontal plate; one end of the horizontal plate is fixedly connected to the sidewall. To ensure the suspension of the horizontal plate, a support portion can be provided on the opposite side end, with the substrate 8 providing stability support for the suspended end of the horizontal plate. Alternatively, support portions can be provided on the other three side ends to provide stable support for the horizontal plate.

[0084] In another specific embodiment, a support structure is formed based on the substrate 8 of the non-effective element area. The support structure can be similar to a "table" structure, including a horizontal plate and multiple support parts for supporting the horizontal plate. The getter 1 can be mainly prepared based on the horizontal plate; it is completely supported by the substrate 8 and does not rely on the packaging cap 3 to achieve a stable and effective suspension support effect, providing basic conditions for the inverted preparation of the getter 1.

[0085] It is understandable that in order to avoid completely sealing the blind element array 7, the supporting parts in the above two ways of forming the supporting structure can be specifically supporting legs, which are supported in the form of rods or narrow plates.

[0086] It is understandable that the area of ​​the horizontal plate in the above two ways of forming the support structure can be adaptively adjusted based on the occupied area of ​​the blind element array 7 and the non-effective element region:

[0087] When the support structure is realized based on the side wall of the packaging cap 3, the area of ​​the horizontal plate is expanded, and the three side ends of the horizontal plate are respectively fixed to the three side walls to form a relatively stable suspension effect; of course, a support part can also be used at the remaining side end to provide stability support based on the substrate 8.

[0088] When the support structure is realized based on the substrate 8, the area of ​​the horizontal plate can be slightly larger than the occupied area of ​​the blind element array 7, but should be smaller than the occupied area of ​​the non-effective element area to avoid affecting the functional utility of the effective element array 6 in the effective element area.

[0089] Based on the two aforementioned support structure implementations, the preparation of getter 1 on a horizontal plate is used as an example. The getter material can be deposited on the upper or lower surface, or both, of the horizontal plate, and the desired dosage of getter 1 can be adjusted. It is understood that this method significantly enhances the dosage selectivity of the getter 1 preparation, enabling a sustained high vacuum environment to be maintained within the cavity.

[0090] It is understandable that, based on the deposition position of the getter 1 on the horizontal plate, a protective film layer 2 may be provided on the outer side of the getter 1 to protect the entire deposited getter 1 and prevent it from being activated prematurely.

[0091] It is understood that when a permanent support structure is used, the composition of the encapsulation cap 3 does not need to be changed. A release hole 4 and an infrared film 32 can still be provided in the structural cavity 31 to achieve a sealing effect. The encapsulation cap 3 does not produce a cover plate, and is adaptable to the two aforementioned methods of inverting the getter 1.

[0092] In other feasible embodiments, the blind element array 7 may not be set on the substrate 8, but a blank area is reserved on the substrate 8 as a non-valid element area, and the getter 1 is suspended above the blank area to ensure that the position of the getter 1 is higher than the valid element array 6; the method for suspending the getter 1 may be similar to that of the aforementioned embodiment and will not be repeated here.

[0093] Example 2

[0094] According to a second aspect of the present invention, a method for preparing an array-level packaged uncooled infrared detector is provided, as shown in Figures 2 to 10 , which specifically includes:

[0095] S1. Prepare or provide a substrate;

[0096] S2, dividing the substrate into an effective element region and an ineffective element region, and manufacturing an effective element array in the effective element region;

[0097] S3, making a suspended getter in the non-effective element area;

[0098] S4, making a packaging cap covering the substrate.

[0099] In the embodiments of the present application, substrate 8 can be an existing product or fabricated based on actual needs. Referring to FIG2 , substrate 8 can be pre-divided into active element regions, while the remaining regions on the substrate are inactive element regions. The MEMS microbridge structures for active element arrays 6 and blind element arrays 7 can be fabricated in corresponding regions on substrate 8, thereby achieving the configuration of active element arrays 6 and blind element arrays 7 through partitioning.

[0100] In the embodiment of the present application, the area occupied by the blind element array 7 may be smaller than the area occupied by the effective element array 6 , and the area of ​​the blind element array 7 may be adjusted or evenly configured according to the dosage of the getter 1 used.

[0101] It is understandable that when depositing the getter 1, a slightly larger area of ​​the getter 1 can be deposited first, and then trimmed to correspond to the blind element array 7, so as to facilitate external positioning and activation; when activating, thermal activation can be performed on the area where the blind element array 7 is located.

[0102] As a method for preparing a suspended getter, a sacrificial layer 5 can be used as a temporary support to prepare the getter 1:

[0103] Therefore, step S3 may specifically include:

[0104] S311, making a sacrificial layer on the structure made in step S2;

[0105] S321 , depositing a getter material on the sacrificial layer to form a whole getter.

[0106] 2 and 3 , the sacrificial layer 5 can be divided into two layers. The first layer 51 is formed based on the substrate 8 , and the second layer 52 is formed by spin coating and deposition again on the first layer 51 and the MEMS microstructure. The final effect is shown in FIG3 .

[0107] Referring to FIG. 4 , in this application, a photoresist 9 can be used to design the desired getter 1 deposition pattern. The designed area corresponds to the blind element array 7 within the non-active element region. The photoresist 9 can be first applied to the second layer 52 , and then, through a photolithography process, the desired getter 1 deposition area is opened, while the remaining areas are covered with the photoresist 9 . It is understood that the getter 1 in the remaining areas is the getter material outside the desired getter 1 pattern.

[0108] For example, after the getter 1 is supported upside down by the sacrificial layer 5, the sacrificial layer 5 can be released after step S4. Therefore, after step S4, the process further includes releasing the sacrificial layer, so that the entire getter formed in step S321 is suspended upside down below the package cap, and the getter is positioned higher than the active element array. Specifically, the sacrificial layer 5 can be released after the structural cavity is formed.

[0109] When the getter 1 is inverted as described in step S3 above, the sacrificial layer 5 is used to temporarily support the getter 1. After completing the relevant process, the sacrificial layer 5 is released. In order to prevent the getter 1 from being activated when the sacrificial layer 5 is activated, a protective film layer 2 can be provided between the getter 1 and the sacrificial layer 5 to prevent the sacrificial layer 5 from affecting the getter 1 when it is activated.

[0110] Therefore, step S321 can be improved and optimized by adding a design step of the protective film layer 2. Specifically, the protective film layer material can be first deposited on the sacrificial layer to form a protective film layer; then, the getter material can be deposited on the protective film layer to form a whole piece of getter.

[0111] It is understandable that if the sacrificial layer 5 can be released without activating the getter 1 , the protective film layer 2 may not be added; otherwise, the protective film layer 2 may be added.

[0112] It should be noted that the release of the sacrificial layer 5 may be thermally activated, and the activation temperature should be below the clustering temperature of the protective film layer 2 .

[0113] The following description will be made by taking the addition of the protective film layer 2 as an example (if the addition of the protective film layer 2 is not required, the relevant process description can be ignored):

[0114] Please refer to Figure 5. A protective layer and a getter layer are sequentially deposited on the pattern formed by the photoresist 9, corresponding to the protective film layer 2 and the getter 1 respectively. The deposited protective layer and getter layer are deposited based on the second layer 52 in the required deposition area, and the remaining areas are deposited based on the photoresist 9.

[0115] Please refer to FIG6 . When the photoresist 9 is stripped by the stripping process, the protective film layer 2 and the getter 1 corresponding to the area where the effective element array 6 is located can be completely stripped, while the protective film layer 2 and the getter 1 corresponding to the area where the blind element array 7 is located are retained.

[0116] Referring to Figure 7 , the first portion of the encapsulation cap 3, namely the structural cavity 31, is fabricated on the patterned getter 1. The structural cavity 31 includes a top plate structure and a peripheral guard plate structure. The structural cavity 31 can be fabricated in stages during deposition. The peripheral guard plate structure can be deposited first, followed by an inverted top plate structure deposited underneath the getter 1. Once completed, the getter 1 can be flipped over to create an upside-down suspended structure.

[0117] It can be understood that after the complete structural cavity 31 is formed, the upper surface of the getter 1 is connected to the inner side of the structural cavity 31, and the getter 1 has initially achieved an inverted suspension setting. After releasing the sacrificial layer 5, the getter 1 can be attached to the structural cavity 31 to achieve inverted suspension.

[0118] Please refer to Figure 8. A release hole 4 for releasing the sacrificial layer 5 can be opened on the top plate structure. Based on the design pattern of the photoresist 9, a through-hole structure corresponding to the release hole 4 can be preset in the getter 1 and the protective film layer 2 to achieve effective operation of the release hole 4 in the inverted area.

[0119] Please refer to FIG. 9 , which is a schematic diagram of the structure after the sacrificial layer 5 is released. When the sacrificial layer 5 is released, the first layer 51 and the second layer 52 can be released at the same time.

[0120] Please refer to FIG10 , the second portion of the packaging cap 3 , namely the infrared film 32 , is packaged on the structural cavity 31 to seal the release hole 4 , thereby achieving a sealing effect of the sealed cavity and realizing high vacuum after activating the getter 1 .

[0121] In the embodiment of the present application, when the protective film layer 2 is subjected to high temperature, clusters are generated, which can directly leak out the protected desiccant 1. Under the continuous influence of high temperature, the desiccant 1 can be activated and absorb the gas in the encapsulated inner cavity, ultimately achieving a vacuum effect.

[0122] As another method for preparing a suspended getter, a support structure can be used as a permanent support to achieve the preparation of the getter 1:

[0123] Therefore, step S3 specifically includes:

[0124] S312, manufacturing a support structure in the non-active element area above the substrate;

[0125] S322 , depositing a getter material on the surface of the support structure to form a whole piece of getter.

[0126] Since the support structure is a permanent support and does not need to be removed, it does not matter whether the release hole 4 is opened on the structural cavity 31 or not. The preparation of the protective film layer 2 of the getter 1 is preferably prepared.

[0127] As a method of manufacturing a support structure, when manufacturing the support structure, a "table"-like structure can be set in the non-effective element area based on the substrate 8, and located on the blind element array 7. Specifically, it can include a horizontal plate and multiple support parts for supporting the horizontal plate. The getter 1 can be mainly prepared based on the horizontal plate; it is completely supported by the substrate 8, and a stable and effective suspension support effect can be achieved without relying on the packaging cap 3, providing basic conditions for the inverted preparation of the getter 1.

[0128] It is understood that this type of support structure can be fabricated after the effective element array 6 and blind element array 7 are fabricated. This fabrication can be completed first, without changing the detailed fabrication process of steps S1 through S4 described above. The support structure on substrate 8 may not be used for wiring or routing of the readout circuitry, but may simply provide physical support.

[0129] As another method of making the support structure, when making the support structure, a horizontal plate suspended on the blind element array 7 can be set on the side wall of the base packaging cap 3, and the getter 1 is prepared based on the suspended horizontal plate; in order to enhance the suspension stability of the horizontal plate, a support portion can be set at the suspended side end of the horizontal plate, and stability support can be provided by means of the substrate 8.

[0130] It is understood that when preparing this type of support structure, the relevant sidewalls of the structural cavity 31 can be prepared first. Then, whether to provide stability support based on the substrate 8 can be determined as needed. After the support structure is prepared, the suspended getter 1 can be prepared. Finally, the other structures of the packaging cap 3 are completed. This does not conflict with the main preparation process of steps S1 to S4 described above, and only requires a few adjustments to the specific detailed process.

[0131] Based on the form of the above-mentioned support structure, when the getter 1 is prepared based on the support structure, the getter material can be deposited on the surface of the support structure, the upper surface, the lower surface, or both the upper and lower surfaces, and finally form an upper layer getter form or a lower layer getter form or both the upper and lower layers have getter forms, wherein the upper layer getter is shown in Figure 11 and the lower layer getter is shown in Figure 12; when both the upper and lower layers have, the amount of the two layers of getter can be different or the same.

[0132] Specifically, the deposition amount of the getter material in the above various forms can be adjusted according to the actual required dosage of the getter 1. However, it should be noted that the deposition amount of the getter 1 in this manner is significantly larger, and a high vacuum can be formed continuously for a long time.

[0133] Similarly, the protection concept when using a sacrificial layer to prepare a suspended getter can also be used to provide a protective film layer 2 when using a support structure to prepare a suspended getter. Specifically, the protective film layer 2 is deposited on the outside of the getter 1.

[0134] For example, when the getter 1 is deposited on the upper layer of the support structure, as shown in FIG11 , the protective film layer 2 is deposited on the upper side of the getter 1 ; when the getter 1 is deposited on the lower layer of the support structure, as shown in FIG12 , the protective film layer 2 is deposited on the lower side of the getter 1 .

[0135] In the embodiment of the present application, high temperature thermal activation is used to cluster the protective film layer 2 so that the getter 1 is exposed, thereby activating the getter 1; the process of clustering the protective film layer 2 can be performed before or after step S4.

[0136] It can be understood that when the process of causing the protective film layer 2 to cluster occurs before step S4, the duration of high-temperature activation can be appropriately controlled, and the process can be stopped after the getter 1 is exposed to avoid activating the getter 1 under the continuous influence of high temperature; then, the infrared film 32 is packaged and covered, and the getter 1 can be activated when necessary; when the process of causing the protective film layer 2 to cluster occurs after step S8, the duration of high-temperature activation can be directly controlled to cause the protective film layer 2 to cluster, and until the getter 1 is activated.

[0137] In the embodiment of the present application, the protective film layer 2 can be made of a material that clusters above 300 degrees Celsius and does not react directly with oxygen. The material can preferably be Au (gold), and the final form can be gold foil.

[0138] It should be noted that for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that this application is not limited by the order of the actions described, because according to this application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by this application.

[0139] The above is only an exemplary embodiment of the present disclosure and cannot be used to limit the scope of the present disclosure. That is, any equivalent changes and modifications made according to the teachings of the present disclosure are still within the scope of the present disclosure. After considering the specification and practicing the disclosure herein, those skilled in the art will easily think of the implementation scheme of the present disclosure. This application is intended to cover any variation, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary technical means in the art that are not recorded in the present disclosure. The description and examples are to be regarded as exemplary only, and the scope and spirit of the present disclosure are defined by the claims.

Claims

1. An array-level packaged uncooled infrared detector, characterized in that: The invention comprises a substrate (8), an effective element array (6), and a getter (1); the substrate (8) has an effective element region and an ineffective element region; the effective element array (6) is arranged in the effective element region; the getter (1) is suspended in the ineffective element region, and the getter (1) is located at a position higher than the effective element array (6).

2. The area array packaged uncooled infrared detector according to claim 1, characterized in that: The ineffective element region comprises a blind element region, a blind element array (7) is arranged in the blind element region, and the getter (1) is suspended above the blind element array (7).

3. The area array packaged uncooled infrared detector according to claim 1, characterized in that: It also includes a packaging cap (3), wherein the packaging cap (3) is packaged on the substrate (8) to form a sealed cavity; the effective element array (6) and the getter (1) are both located in the sealed cavity, and the getter (1) is upside down on the inner side of the packaging cap (3).

4. The area array packaged uncooled infrared detector according to claim 3, characterized in that: The packaging cap (3) comprises a structural cavity (31) and an infrared film (32), wherein the infrared film (32) is located outside the structural cavity (31), and the getter (1) is hung upside down inside the structural cavity (31).

5. The area array packaged uncooled infrared detector according to claim 4, characterized in that: The structural cavity (31) is provided with a release hole (4) for releasing the sacrificial layer; the getter has a through hole corresponding to the release hole (4) above the non-effective element region.

6. The area array packaged uncooled infrared detector according to claim 1, characterized in that: A support structure is arranged above the ineffective element region, and the getter (1) is supported above the support structure and / or the getter (1) is hung upside down below the support structure.

7. The area array packaged uncooled infrared detector according to claim 1, characterized in that: The getter (1) is continuously arranged in an entire piece above the ineffective element area.

8. The area array packaged uncooled infrared detector according to claim 1, characterized in that: A protective film layer (2) is provided on the surface of the getter (1).

9. The area array level packaged uncooled infrared detector according to claim 8, characterized in that: The protective film layer (2) is made of a material that forms clusters above 300 degrees Celsius and does not react directly with oxygen.

10. A method for preparing an array-level packaged uncooled infrared detector, characterized in that: include: S1. Produce or provide a substrate; S2, dividing the substrate into an effective element region and an ineffective element region, and manufacturing an effective element array in the effective element region; S3, making a suspended getter in the non-effective element area; S4, making a packaging cap to cover the substrate.

11. The method for preparing an area array level packaged uncooled infrared detector according to claim 10, characterized in that: The step S3 specifically includes: S311, making a sacrificial layer on the structure made in step S2; S321, depositing a getter material on the sacrificial layer to form a whole getter; After step S4, the method further includes: The sacrificial layer is released, so that the whole getter formed in step S321 is upside down under the packaging cap, and the position of the getter is higher than the effective cell array.

12. The method for preparing an area array level packaged uncooled infrared detector according to claim 11, characterized in that: The step S321 specifically includes: Firstly, a protective film layer material is deposited on the sacrificial layer to form a protective film layer; then, a getter material is deposited on the protective film layer to form a whole piece of getter.

13. The method for preparing an area array level packaged uncooled infrared detector according to claim 10, characterized in that: The step S3 specifically includes: S312, manufacturing a support structure in the non-effective element region above the substrate; S322, depositing a getter material on the surface of the support structure to form a whole piece of getter.

14. The method for preparing an area array level packaged uncooled infrared detector according to claim 12, characterized in that: Also includes: The protective film layer is clustered by high temperature thermal activation, so that the getter is exposed, thereby activating the getter.

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