Packaging method of infrared photoelectric detector array and infrared photoelectric detector

Abstract

The invention provides a packaging method of an infrared photoelectric detector array and an infrared photoelectric detector, and relates to the technical field of detector packaging. The packaging method comprises the following steps: firstly, manufacturing a plurality of second substrates on a first substrate, wherein the plurality of second substrates are of graphical structures; manufacturing a periodic super lens unit array on the second substrate; sputtering a thin film getter on the periphery of the super lens; a first bonding ring is connected to the periphery of the thin film getter through a sputtering process, and a second bonding ring is connected to the periphery of the detector wafer; the first bonding ring and the second bonding ring are connected, so that the super lens and the detector wafer are in a vacuum sealing state; the thin film getter is activated to maintain a vacuum seal state. According to the method, the material with high transmissivity in the infrared band is used as the super lens substrate and the periodic super lens unit array, the light transmissivity of the infrared photoelectric detector is improved, and the second substrate is of a graphical structure, so that the production efficiency of the infrared photoelectric detector is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of detector packaging technology, and in particular to a packaging method for an infrared photodetector array and an infrared photodetector. Background Art

[0002] In the field of optoelectronics, the performance of optoelectronic core devices continues to improve with advancements in materials and processes. Due to their compact size, further optimization of optoelectronic devices can be achieved through optimization of their packaging methods, thereby enhancing their performance and stability. Specifically, packaging technology for uncooled infrared detector arrays is moving towards miniaturization and integration to meet the demands of low cost, high heat dissipation, and large-scale production.

[0003] Currently, wafer-level packaging (WLP) is a common packaging technology for uncooled infrared detector arrays, offering advantages such as small size, low cost, and suitability for large-scale production. Traditional WLP structures utilize a flat lens with a convex lens function for focusing, and an anti-reflection coating is deposited on the surface of the convex lens to improve light transmittance. The packaging process also involves processing and bonding the cover wafer, and then dicing and other steps to form individual detectors.

[0004] However, the infrared photodetectors produced by traditional wafer-level packaging have a high light reflectivity, which is prone to generate interference noise and affect the photoelectric performance of the detector; although the convex lens flat lens used in this technology is treated with an anti-reflection film, it still has a high reflection efficiency and can only achieve small-angle light focusing, which cannot meet the high-precision detection needs in complex environments; in addition, in the traditional packaging process, the cover wafer needs to be cut into individual chip caps, which is not conducive to large-scale production and reduces the production efficiency of infrared photodetectors. Summary of the Invention

[0005] To solve the above problems, the present application provides a packaging method for an infrared photodetector array and an infrared photodetector, which can solve the technical problems that the infrared photodetector after packaging has high light reflectivity and generates interference noise, resulting in reduced performance of the infrared photodetector, and the packaging process is complex, resulting in low production efficiency.

[0006] To achieve the above-mentioned objectives, the first aspect of the present application provides a packaging method for an infrared photodetector array, which uses a photolithography process to produce multiple second substrates on a first substrate, the first substrate and the multiple second substrates are materials with high transmittance in the infrared band, and the multiple second substrates are patterned structures; a super lens unit array is produced on the second substrate using photolithography and dry etching processes, and the super lens unit array is a periodic structure; a thin film getter is sputtered on the periphery of the super lens, and the super lens includes a first substrate, a second substrate and a super lens unit array located on the second substrate; a detector wafer is provided, and the detector wafer includes multiple independent infrared photoelectric detection units arranged in an array; a first bonding ring is connected to the periphery of the thin film getter through a sputtering process, and a second bonding ring is connected to the periphery of the detector wafer; the first bonding ring and the second bonding ring are connected so that the super lens and the detector wafer are in a vacuum sealed state; and the thin film getter is activated to maintain the vacuum sealed state.

[0007] In the above packaging method, the use of a material with high infrared transmittance as the metalens substrate can improve the light transmittance of the packaged infrared photodetector. Furthermore, the patterned structure of the second substrate can match the shape of the detector wafer, reducing the complexity of the cutting process and improving the production efficiency of infrared photodetectors. Furthermore, the design of a periodic metalens unit array can improve the infrared photodetector's transmittance over a wide angle range in the mid-infrared band, further improving the light transmittance of the packaged infrared photodetector.

[0008] In an implementation manner of the first aspect, a shape of each second substrate matches a package shape of the infrared photodetection unit.

[0009] In the above packaging method, the shape of the second substrate matches the packaging shape of the infrared photoelectric detection unit, so that the cover wafer and the detector wafer can be tightly combined, thereby improving the accuracy of the packaged infrared photoelectric detector.

[0010] In one implementation of the first aspect, the super lens unit array includes a plurality of super lens units, and the super lens units are periodically arranged on the second substrate, with an arrangement period less than or equal to 1 μm; the arrangement period is equal to the length of the bottom diameter of the super lens unit.

[0011] In the above packaging method, the light transmittance of the super lens is improved by designing a suitable arrangement period, the influence of the interference effect is reduced, and the performance of the infrared photodetector is improved.

[0012] In one implementation of the first aspect, each super lens unit in the super lens unit array is identical, and the super lens units have a symmetrical structure.

[0013] In the above packaging method, the superlens unit array uses superlens units with the same and symmetrical structure, which can improve the light transmittance of the superlens, reduce the influence of interference effect, and improve the performance of infrared photodetectors.

[0014] In an implementation manner of the first aspect, the super lens unit is a super surface structure with a 2π phase change.

[0015] In the above packaging method, the super lens unit adopts a 2π phase super surface structure to destroy the coherent reflection light path and improve the light transmittance of the infrared photodetector.

[0016] In an implementation of the first aspect, the thin film getter is a low-temperature getter with an activation temperature lower than 300° C.; the thin film getter is made of an alloy material, and a width of the thin film getter is greater than 300 μm and less than 600 μm.

[0017] In the above packaging method, selecting a suitable thin film getter width and a suitable activation temperature can improve the precision of infrared photodetector packaging.

[0018] In an implementation manner of the first aspect, the first bonding ring and the second bonding ring are of the same size; and the widths of the first bonding ring and the second bonding ring are greater than 400 μm and less than 600 μm.

[0019] In the above packaging method, the cover wafer and the detector wafer are sealed using a first bonding ring and a second bonding ring of the same size, which can improve the tightness of the seal. Setting a suitable width for the bonding ring can improve the reliability of the packaging.

[0020] In an implementation of the first aspect, a plurality of second substrates are manufactured on the first substrate using a chemical deposition process, and the first substrate and the second substrate are made of the same material; or, a plurality of second substrates are manufactured on the first substrate using a dry etching process.

[0021] In the above packaging method, multiple second substrates can be fabricated on the first substrate using two different processes, either chemical deposition or dry etching, thereby increasing the diversity of packaging methods. Furthermore, when using chemical deposition, it is necessary to ensure that the first and second substrates are made of the same material with high infrared transmittance, which can improve the uniformity and light transmittance of the infrared photodetector. When using dry etching, the second substrate must be made of the same material, which also improves the uniformity and light transmittance of the infrared photodetector.

[0022] In an implementation manner of the first aspect, the height of the superlens is greater than 40% of the operating peak wavelength of the infrared photodetection unit and less than the operating peak wavelength of the infrared photodetection unit.

[0023] In the above packaging method, a metalens with a height between 40% and 100% of the working peak wavelength of the infrared photodetection unit is selected to package the detector wafer, which can improve the light transmittance of the packaged infrared photodetector.

[0024] In the second aspect, the present application also provides an infrared photodetector, which is manufactured based on the packaging method of the infrared photodetector array in the first aspect and any possible implementation method thereof, and the infrared photodetector includes: a cover wafer, the cover wafer includes: a super lens, and a thin film getter arranged on the periphery of the super lens; wherein the super lens includes a first substrate, a plurality of patterned second substrates located on the first substrate, and a super lens unit array located on the second substrate; the detector wafer includes: a substrate and a plurality of independent infrared photodetection units arranged in an array on the substrate; the substrate includes a GaSb substrate layer, a P-type layer, a light-emitting layer, an n-type layer and an electrode; the shape of each second substrate matches the packaging shape of the infrared photodetection unit; a first bonding ring connected to the periphery of the thin film getter, and a second bonding ring connected to the periphery of the detector wafer; wherein the first bonding ring is connected to the second bonding ring so that the cover wafer and the detector wafer form a vacuum sealing structure.

[0025] It can be understood that the beneficial effects that can be achieved by the technical solution of the second aspect provided above can refer to the beneficial effects in the first aspect and any optional implementation method thereof, and will not be repeated here.

[0026] As can be seen from the above technical solutions, the present application provides a packaging method for an infrared photodetector array and an infrared photodetector. The packaging method for the infrared photodetector array comprises the following steps: using a photolithography process to produce a plurality of second substrates on a first substrate, wherein the first substrate and the plurality of second substrates are materials with high transmittance in the infrared band, and the plurality of second substrates are patterned structures; using photolithography and dry etching processes to produce a super lens unit array on the second substrate, wherein the super lens unit array is a periodic structure; sputtering a thin film getter on the periphery of the super lens, wherein the super lens includes a first substrate, a second substrate, and a super lens unit array located on the second substrate; providing a detector wafer, wherein the detector wafer includes a plurality of independent infrared photodetector units arranged in an array; connecting a first bonding ring on the periphery of the thin film getter and connecting a second bonding ring on the periphery of the detector wafer through a sputtering process; connecting the first bonding ring and the second bonding ring so that the super lens and the detector wafer are in a vacuum-sealed state; activating the thin film getter to maintain the vacuum-sealed state.

[0027] In the above packaging method, the use of a material with high infrared transmittance as the metalens substrate can improve the light transmittance of the packaged infrared photodetector. Furthermore, the patterned structure of the second substrate can match the shape of the detector wafer, reducing the complexity of the cutting process and improving the production efficiency of infrared photodetectors. Furthermore, the design of a periodic metalens unit array can improve the infrared photodetector's transmittance over a wide angle range in the mid-infrared band, further improving the light transmittance of the packaged infrared photodetector. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0029] Figure 1 A schematic diagram of a packaging method for an infrared photodetector array provided in an embodiment of the present application; Figure 2 A top view of a super lens structure provided in an embodiment of the present application; Figure 3 A top view of a detector wafer structure provided in an embodiment of the present application; Figure 4 A schematic cross-sectional view of a metalens structure provided in an embodiment of the present application; Figure 5 A schematic diagram of a cover wafer structure provided in an embodiment of the present application; Figure 6 A schematic diagram of a bonding structure provided in an embodiment of the present application.

[0030] Reference numerals: 1-super lens unit; 2-second substrate; 201-super lens unit array; 3-first substrate; 4-super lens; 5-thin film getter; 601-first bonding ring; 602-second bonding ring; 7-infrared photodetection unit; 8-substrate; 9-detector wafer; 10-cover wafer. DETAILED DESCRIPTION

[0031] The following embodiments are described in detail, with examples shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following embodiments are not intended to represent all embodiments consistent with this application.

[0032] It should be noted that the brief descriptions of terms in this application are only for the purpose of facilitating the understanding of the embodiments described below, and are not intended to limit the embodiments of this application. Unless otherwise specified, these terms should be understood according to their ordinary and usual meanings.

[0033] In this specification and the accompanying drawings, the terms "first," "second," "third," etc. are used to distinguish similar or similar objects or entities, and are not necessarily intended to limit a particular order or precedence, unless otherwise noted. It should be understood that the terms used in this manner are interchangeable under appropriate circumstances.

[0034] To facilitate understanding of the solution, the following explains the relevant terms: A superlens is a planar optical element based on a metasurface. Its core principle is to utilize subwavelength-scale artificial nanostructures to precisely control the phase, amplitude, or polarization state of incident light, thereby achieving traditional lens functions such as focusing and imaging.

[0035] Detector wafers: These are semiconductor wafers specifically designed and manufactured for detecting light, particles, or other forms of energy. Their core function is to convert incident energy (such as photons, electrons, X-rays, alpha particles, etc.) into measurable electrical signals.

[0036] Cover wafer: A specialized wafer used in semiconductor manufacturing to seal and protect underlying device wafers (such as detector wafers). Its core function is to provide a physical barrier, isolating sensitive devices from the external environment.

[0037] Thin film getter: refers to an ultra-thin layer of active material deposited on the surface of the device interior (such as a vacuum or hermetic package cavity). Its core function is to actively adsorb or chemically capture harmful gas molecules and pollutants that remain or are slowly released inside the package, thereby maintaining the required high vacuum or pure inert gas environment for a long time.

[0038] Bonding ring: refers to the annular sealing structure designed on the wafer surface in semiconductor manufacturing. Its core function is to achieve precise alignment, firm bonding and airtight sealing between two wafers (such as the detector wafer and the cover wafer).

[0039] In the field of infrared photodetector manufacturing, packaging is necessary to improve the performance, operational stability, and service life of infrared photodetectors. Wafer-level packaging is a commonly used packaging technology, which offers advantages such as small size and low cost.

[0040] The traditional wafer-level packaging structure uses a flat lens with a convex lens function to achieve focusing, and evaporates an anti-reflection film on the surface of the convex lens to improve light transmittance; at the same time, the packaging process involves the processing and bonding of the cover wafer, and a single detector is formed through steps such as dicing.

[0041] Wafer-level packaging technology uses a flat lens with convex lens functionality to achieve focusing. Anti-reflection coating is evaporated on the surface of the convex lens to improve light transmittance. However, the light reflection efficiency is still relatively high, and it can only achieve light focusing at small angles, which cannot meet the needs of high-precision detection in complex environments. Furthermore, the reflected light will generate interference noise, reducing the performance of the detector. Furthermore, in traditional packaging processes, the cover wafer must be cut into individual chip caps, which is not conducive to large-scale production and reduces the production efficiency of infrared photoelectric detectors.

[0042] To solve the above technical problems, an embodiment of the present application provides a packaging method for an infrared photodetector array, which can improve the light transmittance of the packaged infrared photodetector, reduce the reflection loss of infrared light at large angles and the influence of interference effects, and thus improve the performance of the infrared photodetector.

[0043] The packaging method of the infrared photodetector array provided in the embodiment of the present application uses a super lens structure to manufacture a cover wafer 10, and then the cover wafer 10 and the detector wafer 9 are sealed by two bonding rings.

[0044] Figure 1 Schematic diagram of a packaging method for an infrared photodetector array provided in an embodiment of the present application. Figure 1 As shown, the packaging method of the infrared photodetector array includes steps S1-S7.

[0045] Step S1: providing a first substrate 3 .

[0046] Figure 2 This is a top view of a super lens structure provided in an embodiment of the present application. Figure 2 As shown, the bottom layer of the super lens structure is the first substrate 3.

[0047] In some embodiments, the first substrate 3 is made of a material having high transmittance in the infrared band. For example, silicon, germanium, zinc sulfide, or the like is used as the first substrate 3 .

[0048] Step S2: preparing a plurality of second substrates 2 .

[0049] For example Figure 2 As shown, a plurality of second substrates 2 are provided on the upper layer of the first substrate 3 .

[0050] In some embodiments, a plurality of second substrates 2 are fabricated on a first substrate 3 using a photolithography process. The plurality of second substrates 2 are made of a material having high transmittance in the infrared band. For example, silicon, germanium, zinc sulfide, or other materials having high transmittance in the infrared band are used as the second substrates 2.

[0051] In some embodiments, to increase the diversity of packaging methods, two processes, such as chemical deposition or dry etching, can be used to manufacture multiple second substrates 2 on the first substrate 3 .

[0052] In some embodiments, to improve the uniformity of the super lens structure, the first substrate 3 and the second substrate 2 are made of the same material.

[0053] For example, if a chemical deposition process is used to manufacture a plurality of second substrates 2 on a first substrate 3 , both the first substrate 3 and the second substrate 2 are made of silicon.

[0054] For example, if a dry etching process is used to form multiple second substrates 2 on a first substrate 3, and the first substrate 3 is made of silicon, since the dry etching process is performed directly on the first substrate 3, the material of the etched second substrates 2 must be the same as that of the first substrate 3, and the material of the second substrates 2 is also silicon.

[0055] Figure 3 This is a top view of a detector wafer structure provided in an embodiment of the present application. Figure 3 As shown, the detector wafer 9 includes a substrate 8 and a plurality of independent infrared photoelectric detection units 7 arranged in an array on the substrate 8.

[0056] In some embodiments, in order to reduce the process complexity of the infrared photodetector during the packaging process, avoid cutting the cover wafer 10 into individual caps before packaging, and improve the efficiency of large-scale packaging of infrared photodetectors, each second substrate 2 can be made into a graphical structure that matches the shape of the infrared photodetection unit 7 in the detector wafer 9.

[0057] For example, if the infrared photodetection units 7 in the detector wafer 9 are square in shape, each second substrate 2 is fabricated into a square structure. Thus, the packaged infrared photodetector array comprises multiple square infrared photodetectors. The infrared photodetector array can then be cut into individual infrared photodetectors through a dicing process, thereby improving the efficiency of large-scale production of infrared photodetectors.

[0058] It should be understood that the shape of the second substrate 2 can be adjusted according to the packaging requirements of the detector wafer 9, and is not specifically limited in the embodiments of the present application.

[0059] S3: Fabricate the super lens unit array 201.

[0060] For example Figure 2 As shown, each second substrate 2 includes a group of super lens unit arrays 201. In some embodiments, the super lens unit arrays 201 are manufactured on the second substrate 2 by using photolithography and dry etching processes.

[0061] In one implementation, a metalens structure is used to package the detector wafer 9. To improve the light transmittance of the packaged infrared photodetector over a wide angular range in the mid-infrared band, the metalens unit array 201 can be configured as a periodic structure consisting of multiple metalens units 1. Each metalens unit 1 in the metalens unit array 201 is periodically arranged on the second substrate 2. Exemplarily, the arrangement period of the metalens units 1 is less than or equal to 1 μm.

[0062] In some embodiments, to further improve the light transmittance of the packaged infrared photodetector in the wide angle range of the mid-infrared band, each super lens unit 1 in the super lens unit array 201 is configured to have the same structure and a symmetrical structure.

[0063] Figure 4 A schematic cross-sectional view of a superlens structure provided in an embodiment of the present application.

[0064] like Figure 4 As shown, the super lens units 1 in each super lens unit array 201 are all of the same and symmetrical waist-type structure.

[0065] It should be understood that the super lens unit 1 can also have other symmetrical structures, such as cylindrical, truncated cone, etc., which is not specifically limited in the embodiments of the present application.

[0066] Furthermore, to improve the light transmittance of the packaged infrared photodetector over a wide angle range in the mid-infrared band, the arrangement period of the superlens units 1 is set to be equal to the length of the bottom diameter of the superlens units 1. For example, the bottom diameter of the superlens units 1 is 1 μm, and the arrangement period of the superlens units 1 is also 1 μm.

[0067] In other embodiments, to improve light transmittance, a suitable size may be selected for the metalens unit 1. For example, if the metalens unit 1 is a waist-type structure, the waist height of the metalens unit 1 is set to 20%-30% of the height of the metalens unit 1.

[0068] In some further embodiments, the height of the superlens 4 may be set according to the operating peak wavelength of the infrared photodetection unit 7 on the detector wafer 9. For example, the height of the superlens 4 is greater than 40% of the operating peak wavelength of the infrared photodetection unit 7 and less than the operating peak wavelength of the infrared photodetection unit 7.

[0069] In this way, by making a super lens unit array 201 on the second substrate 2 with multiple super lens units 1 having the same specific structure (such as a waist-type symmetrical structure, the waist height is 20% of the overall height, and the height is 40% of the working peak wavelength of the infrared photodetection unit 7), and setting the arrangement period of the super lens unit 1 to be the same as the bottom diameter of the super lens unit 1, the transmittance of the packaged infrared photodetector in the mid-infrared band can be greater than 99% in a large angle range, thereby improving the performance of the infrared photodetector.

[0070] In some embodiments, the metalens unit 1 is a metasurface structure with a 2π phase change, which can focus vertically incident light onto the photosensitive surface of the detector wafer 9, further improving the transmittance of the infrared photodetector to the incident light.

[0071] S4: Sputtering thin film getter 5.

[0072] Figure 5 A schematic diagram of a cover wafer structure provided in an embodiment of the present application.

[0073] like Figure 5 As shown, the cover wafer 10 for packaging the detector wafer 9 includes a super lens 4 consisting of a first substrate 3, a second substrate 2 and a super lens unit array 201 located on the second substrate 2, a thin film getter 5 and a first bonding ring 601.

[0074] In some embodiments, in order to achieve sealing between the cover wafer 10 and the detector wafer 9 , a thin film getter 5 needs to be sputtered on the periphery of the superlens 4 first.

[0075] In one implementation, to prevent high temperature from damaging the detector wafer 9 , the thin film getter 5 is a low-temperature getter with an activation temperature below 300° C. For example, the thin film getter 5 with an activation temperature of 200° C. is sputtered on the periphery of the superlens 4 .

[0076] In another implementation, to improve the stability of the packaged device, the thin film getter 5 can be made of an alloy material, and the width of the thin film getter 5 can be set between 300 μm and 600 μm. For example, Ti-V or Ti-Zr-V is selected as the thin film getter 5, and the width of the thin film getter 5 sputtered around the outer periphery of the superlens 4 is 400 μm.

[0077] Step S5: providing a detector wafer 9.

[0078] In some embodiments, after the cover wafer 10 is prepared, the detector wafer 9 can be provided, and the sealing operation of the cover wafer 10 and the detector wafer 9 can be continued.

[0079] Step S6: Connecting the bonding rings.

[0080] In some embodiments, after the cover wafer 10 and the detector wafer 9 are prepared, they need to be sealed to achieve the packaging of the infrared photodetector array.

[0081] In one implementation, in order to avoid cutting the cover wafer 10 into individual caps before performing the sealing operation, a chip-to-wafer bonding process can be used. Since the chip-to-wafer bonding process can integrate different process nodes on the same wafer, it breaks through the manufacturing limitations of a single wafer. Therefore, by using the chip-to-wafer bonding process, the cover wafer 10 including multiple super lens unit arrays 201 and the detector wafer 9 including multiple infrared photodetection units 7 are bonded to improve the efficiency of large-scale production.

[0082] Figure 6 A schematic diagram of a bonding structure provided in an embodiment of the present application.

[0083] In one implementation, first, a first bonding ring 601 is connected to the periphery of the thin film getter 5 and a second bonding ring 602 is connected to the periphery of the detector wafer 9 by a sputtering process.

[0084] In some embodiments, to improve the stability of the packaging structure, a first bonding ring 601 and a second bonding ring 602 of the same size are connected to the periphery of the thin-film getter 5 and the periphery of the detector wafer 9, and the widths of the first bonding ring 601 and the second bonding ring 602 are set to be 400 μm-600 μm. For example, a first bonding ring 601 with a width of 500 μm and a second bonding ring 602 with a width of 500 μm are connected to the periphery of the thin-film getter 5 and the periphery of the detector wafer 9, respectively.

[0085] Next, the first bonding ring 601 and the second bonding ring 602 are connected to make the metalens 4 and the detector wafer 9 in a vacuum-sealed state. Figure 6 As shown, the first bonding ring 601 and the second bonding ring 602 are tightly connected to achieve the effect of sealing the metalens 4 and the detector wafer 9.

[0086] Finally, the thin film getter 5 is activated to maintain the vacuum sealing state.

[0087] Based on the above steps S1-S6, the packaging of the detector wafer 9 using the metalens 4 having a specific structure and a periodic arrangement is completed. Since the packaging process uses the metalens 4 having multiple metalens unit arrays 201 and the detector wafer 9 having multiple infrared photodetection units 7, the packaged infrared photodetector array can be cut through a dicing process to obtain individual infrared photodetectors.

[0088] The present embodiment proposes a packaging method for an infrared photodetector array. A cover wafer 10 is formed by using a metalens unit 1 having a specific structure and periodically arranged in a certain ratio to package a detector wafer 9. It should be understood that this cover wafer 10 can also be used to package other medium-wave and short-wave uncooled infrared detector devices, and this is not specifically limited in the present embodiment.

[0089] An embodiment of the present application also provides an infrared photodetector, which is manufactured based on the packaging method of the infrared photodetector array in the above embodiment. The infrared photodetector includes: a cover wafer 10, the cover wafer 10 includes: a super lens 4, and a thin film getter 5 arranged on the periphery of the super lens 4; wherein the super lens 4 includes a first substrate 3, a plurality of patterned second substrates 2 located on the first substrate 3, and a super lens unit array 201 located on the second substrate 2; a detector wafer 9, including: a substrate 8 and a plurality of independent infrared photodetection units 7 arranged in an array on the substrate 8; the substrate 8 includes a GaSb substrate layer, a P-type layer, a light-emitting layer, an n-type layer and an electrode; the shape of each second substrate 2 matches the packaging shape of the infrared photodetection unit 7; a first bonding ring 601 connected to the periphery of the thin film getter 5, and a second bonding ring 602 connected to the periphery of the detector wafer 9; wherein the first bonding ring 601 is connected to the second bonding ring 602, so that the cover wafer 10 and the detector wafer 9 form a vacuum sealing structure.

[0090] It can be seen from the above technical solutions that the present application provides a packaging method for an infrared photoelectric detector array and an infrared photoelectric detector. Among them, the packaging method of the infrared photodetector array adopts a photolithography process to produce multiple second substrates 2 on a first substrate 3, the first substrate 3 and the multiple second substrates 2 are materials with high transmittance in the infrared band, and the multiple second substrates 2 are patterned structures; a super lens unit array 201 is produced on the second substrate 2 by photolithography and dry etching processes, and the super lens unit array 201 is a periodic structure; a thin film getter 5 is sputtered on the periphery of the super lens 4, and the super lens 4 includes a first substrate 3, a second substrate 2 and a super lens unit array 201 located on the second substrate 2; a detector wafer 9 is provided, and the detector wafer 9 includes multiple independent infrared photoelectric detection units 7 arranged in an array; a first bonding ring 601 is connected to the periphery of the thin film getter 5 by a sputtering process, and a second bonding ring 602 is connected to the periphery of the detector wafer 9; the first bonding ring 601 and the second bonding ring 602 are connected to make the super lens 4 and the detector wafer 9 in a vacuum sealed state; and the thin film getter 5 is activated to maintain the vacuum sealed state.

[0091] In the above-described packaging method, the use of a material with high infrared transmittance as the metalens substrate improves the light transmittance of the packaged infrared photodetector. Furthermore, the patterned structure of the second substrate 2 matches the shape of the detector wafer 9, reducing the complexity of the cutting process and improving the production efficiency of the infrared photodetector. Furthermore, the design of a periodic metalens unit array 201 can enhance the infrared photodetector's transmittance over a wide range of angles in the mid-infrared band, further improving the light transmittance of the packaged infrared photodetector.

[0092] Similar parts between the embodiments provided in this application can be referenced to each other. The specific implementation methods provided above are only a few examples under the overall concept of this application and do not constitute a limitation on the scope of protection of this application. For those skilled in the art, any other implementation methods expanded based on the scheme of this application without expending creative work shall fall within the scope of protection of this application.

Claims

1. A packaging method for an infrared photodetector array, characterized in that: A plurality of second substrates (2) are manufactured on a first substrate (3) using a photolithography process, wherein the first substrate (3) and the plurality of second substrates (2) are made of materials having high transmittance in the infrared band, and the plurality of second substrates (2) are patterned structures; A super lens unit array (201) is manufactured on the second substrate (2) by using photolithography and dry etching processes, wherein the super lens unit array (201) is a periodic structure; Sputtering a thin film getter (5) on the periphery of a superlens (4), wherein the superlens (4) comprises the first substrate (3), the second substrate (2), and the superlens unit array (201) located on the second substrate (2); Providing a detector wafer (9), wherein the detector wafer (9) includes a plurality of independent infrared photoelectric detection units (7) arranged in an array; Connecting a first bonding ring (601) to the periphery of the thin film getter (5) and connecting a second bonding ring (602) to the periphery of the detector wafer (9) through a sputtering process; connecting the first bonding ring (601) and the second bonding ring (602) so that the metalens (4) and the detector wafer (9) are in a vacuum-sealed state; The thin film getter (5) is activated to maintain the vacuum sealing state.

2. The packaging method of the infrared photodetector array according to claim 1, characterized in that: The shape of each second substrate (2) matches the packaging shape of the infrared photoelectric detection unit (7).

3. The packaging method of the infrared photodetector array according to claim 1, characterized in that: The super lens unit array (201) comprises a plurality of super lens units (1), and the super lens units (1) are periodically arranged on the second substrate (2), with an arrangement period of less than or equal to 1 μm; The arrangement period is equal to the length of the bottom diameter of the super lens unit (1).

4. The packaging method of the infrared photodetector array according to claim 3, characterized in that: Each of the super lens units (1) in the super lens unit array (201) is identical, and the super lens units (1) are symmetrical structures.

5. The packaging method of the infrared photodetector array according to claim 4, characterized in that: The super lens unit (1) is a super surface structure with a 2π phase change.

6. The packaging method of the infrared photodetector array according to claim 1, characterized in that: The thin film getter (5) is a low-temperature getter with an activation temperature lower than 300°C; The thin film getter (5) is made of an alloy material, and the width of the thin film getter (5) is greater than 300 μm and less than 600 μm.

7. The packaging method of the infrared photodetector array according to claim 6, characterized in that: The first bonding ring (601) and the second bonding ring (602) are of the same size; The width of the first bonding ring (601) and the second bonding ring (602) is greater than 400 μm and less than 600 μm.

8. The packaging method of the infrared photodetector array according to claim 1, characterized in that: A plurality of second substrates (2) are produced on the first substrate (3) using a chemical deposition process, wherein the first substrate (3) and the second substrate (2) are made of the same material; Alternatively, a plurality of the second substrates (2) are produced on the first substrate (3) using a dry etching process.

9. The packaging method of the infrared photodetector array according to claim 1, wherein: The height of the super lens (4) is greater than 40% of the operating peak wavelength of the infrared photoelectric detection unit (7) and less than the operating peak wavelength of the infrared photoelectric detection unit (7).

10. An infrared photodetector, manufactured based on the packaging method of the infrared photodetector array according to any one of claims 1 to 9, characterized in that: include: A cover wafer (10) comprising: a superlens (4), and a thin film getter (5) disposed on the periphery of the superlens (4); wherein the superlens (4) comprises a first substrate (3), a plurality of patterned second substrates (2) located on the first substrate (3), and a superlens unit array (201) located on the second substrate (2); A detector wafer (9) comprising: a substrate (8) and a plurality of independent infrared photoelectric detection units (7) arranged in an array on the substrate (8); the substrate (8) comprising a GaSb substrate layer, a P-type layer, a light-emitting layer, an n-type layer, and an electrode; the shape of each second substrate (2) matches the package shape of the infrared photoelectric detection unit (7); a first bonding ring (601) connected to the periphery of the thin film getter (5), and a second bonding ring (602) connected to the periphery of the detector wafer (9); The first bonding ring (601) is connected to the second bonding ring (602), so that the cover wafer (10) and the detector wafer (9) form a vacuum sealing structure.

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