An infrared detector

Abstract

The present invention relates to an infrared detector, comprising a plurality of bridge deck layers arranged in an array and a plurality of readout circuit interfaces configured in a one-to-one correspondence, each of which is connected to a readout circuit; and also comprising a plurality of common bridge legs, each of which is connected to two adjacent bridge deck layers in a column direction through two upper anchor columns, and the common bridge legs are electrically connected to the corresponding two readout circuit interfaces through a lower connection structure. The present invention can significantly increase the length of the bridge legs by having two bridge deck layers share the same common bridge leg, that is, two adjacent pixel elements in a column direction share the same common bridge leg, thereby greatly reducing thermal conductivity and significantly improving the performance of the detector; without affecting the performance of the detector, the width and spacing of the common bridge legs can be adjusted, so that the bridge leg etching and film growth processes are not affected by the deviation of the machine within the effective redundant range of the machine, which can effectively improve the process uniformity, repeatability and controllability of the detector and improve the product yield of the detector.

Description

Technical Field

[0001] The invention relates to an infrared detector. Background Art

[0002] As pixels become smaller and smaller, the space for uncooled infrared devices will also become smaller and smaller, so it is necessary to improve the performance of detectors within a limited space. In an uncooled infrared focal plane detector array, the readout circuit reads and outputs by selecting row by row and outputting by column, that is, after a row of pixels is selected, the pixels in this row are collected and output one by one as useful signals; at this time, the pixels in the upper and lower rows adjacent to this row are not working, so there is a certain amount of idle space. Summary of the invention

[0003] The present invention relates to an infrared detector, which can at least solve some defects of the prior art.

[0004] The present invention relates to an infrared detector, comprising a plurality of bridge deck layers arranged in an array and a plurality of readout circuit interfaces configured in one-to-one correspondence, wherein each of the readout circuit interfaces is connected to a readout circuit, and also comprising a plurality of common bridge legs, wherein each of the common bridge legs is respectively connected to two adjacent bridge deck layers in a column direction through two upper anchor columns, and the common bridge legs are respectively electrically connected to the corresponding two readout circuit interfaces through a lower connection structure.

[0005] As one of the implementation modes, one common bridge leg is configured for every two rows of adjacent bridge decks.

[0006] As one of the implementation modes, the two upper anchor columns connected to each bridge deck are respectively close to the two row ends of the bridge deck.

[0007] As one of the implementation modes, the lower connection structure includes a lower anchor column and a metal connection layer, the metal connection layer is electrically connected to the corresponding two readout circuit interfaces respectively, and the lower anchor column is arranged on the upper surface of the metal connection layer and supports the corresponding common bridge leg.

[0008] As one of the implementation modes, the common bridge leg is in a serpentine structure, and the upper connection structure composed of two corresponding upper anchor columns and the lower connection structure are respectively located at the head and tail sides of the common bridge leg.

[0009] The present invention has at least the following beneficial effects:

[0010] The infrared detector provided by the present invention can significantly increase the length of the bridge leg by having two bridge deck layers share the same common bridge leg, that is, two adjacent pixels in the column direction share a common bridge leg, thereby greatly reducing thermal conductivity and significantly improving the performance of the detector. Without affecting the performance of the detector, the width and spacing of the common bridge leg can be adjusted, so that the bridge leg etching and film growth processes are not affected by the machine deviation within the effective redundant range of the machine, thereby effectively improving the process uniformity, repeatability and controllability of the detector, thereby improving the product yield of the detector. In addition, since one bridge leg has multiple support points and two bridge deck pull-ups, the device structure of the detector will be very stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0012] Figure 1 A schematic diagram of the structure of an infrared detector provided by an embodiment of the present invention;

[0013] Figure 2 A schematic diagram of the distribution structure of a single bridge deck and a common bridge leg provided in an embodiment of the present invention;

[0014] Figure 3 A schematic diagram of the distribution structure of adjacent bridge deck layers and common bridge legs provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0015] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] like Figure 1-Figure 3 An embodiment of the present invention provides an infrared detector, comprising a plurality of bridge deck layers 1 arranged in an array and a plurality of readout circuit interfaces 3 configured in a one-to-one correspondence, each of the readout circuit interfaces 3 being connected to a readout circuit (not shown), and comprising a plurality of common bridge legs 2, each of the common bridge legs 2 being connected to two adjacent bridge deck layers 1 in a column direction through two upper anchor columns 5, and the common bridge legs 2 being electrically connected to the corresponding two readout circuit interfaces 3 through a lower connection structure.

[0017] The bridge deck 1, the readout circuit and the readout circuit interface 3, the anchor column, etc. are all conventional devices in the field, and the specific structure is not described here. It can be understood that the number of bridge decks 1 and the readout circuit interface 3 is the same and they are configured one by one. Generally, the readout circuit interface 3 is arranged directly below the corresponding bridge deck 1.

[0018] In the uncooled infrared focal plane detector array, the reading and outputting mode of the readout circuit is to select row by row and output column by column, that is, after a row of pixels is selected, the pixel points of this row are collected and output one by one as useful signals. Therefore, the row direction and column direction involved in this embodiment are the row arrangement direction and column arrangement direction in the bridge deck layer 1 arranged in the array, which is easy to understand for those skilled in the art.

[0019] The common bridge leg 2 may adopt a conventional bridge leg structure in the art, such as a conventional bridge leg material; preferably, the common bridge leg 2 is a serpentine structure, which can greatly increase the length of the common bridge leg 2, which is beneficial to the improvement of the detector performance. Figure 2 and Figure 3 The two upper anchor columns 5 corresponding to each common bridge leg 2 form an upper connection structure. The upper connection structure and the above-mentioned lower connection structure are respectively located on the head and tail sides of the corresponding common bridge leg 2, which can correspondingly increase the length of the common bridge leg 2, extend the signal conduction distance, effectively reduce thermal conductivity, and the structural stability of the common bridge leg 2 is also relatively high.

[0020] In one embodiment, if Figure 1 , the lower connection structure includes a lower anchor column 61 and a metal connection layer 62, the metal connection layer 62 is electrically connected to the corresponding two readout circuit interfaces 3, the lower anchor column 61 is arranged on the upper surface of the metal connection layer 62 and supports the corresponding common bridge leg 2; wherein, Figure 1 , the metal connection layer 62 can be connected to the corresponding two readout circuit interfaces 3 through the transition anchor column 63. The lower connection structure can realize the reliable connection between the common bridge leg 2 and the corresponding two readout circuit interfaces 3; because one bridge leg has three supporting points (i.e., the lower anchor column 62 connected to the readout circuit interface 3 and two adjacent upper anchor columns 5) and two bridge surface pull-ups, the device structure of the detector will be very stable.

[0021] In the above detector, the common bridge leg 2 support design can be performed on part of two adjacent bridge deck layers 1 in the column direction, but it is more preferred to configure one common bridge leg 2 for every two adjacent bridge deck layers 1 in the column direction. More specifically, Figure 1-Figure 3, taking three bridge decks 1 arranged in sequence in a column direction as an example, the three bridge decks 1 are defined as the first bridge deck 1, the second bridge deck 1 and the third bridge deck 1 in sequence, each bridge deck 1 is supported by two upper anchor columns 5, and the two upper anchor columns 5 are respectively connected to two common bridge legs 2; wherein the second bridge deck 1 is supported by the first common bridge leg 2 and the second common bridge leg 2, and the other upper anchor column 5 configured for the first common bridge leg 2 supports the first bridge deck 1, and the first common bridge leg 2 is partially located directly below the first bridge deck 1 and partially located directly below the second bridge deck 1, and the other upper anchor column 5 configured for the second common bridge leg 2 supports the third bridge deck 1, and the second common bridge leg 2 is partially located directly below the second bridge deck 1 and partially located directly below the third bridge deck 1. In one embodiment, as Figure 1 The common bridge legs 2 are arranged in the same horizontal plane, and the arrangement structure is simple, which can ensure the support reliability of the bridge deck layer 1.

[0022] More preferably, if Figure 2 and Figure 3 The two upper anchor columns 5 connected to each bridge deck 1 are respectively close to the two row ends of the bridge deck 1, that is, one of the upper anchor columns 5 is close to one row-adjacent bridge deck 1 of the bridge deck 1, and the other upper anchor column 5 is close to the other row-adjacent bridge deck 1 of the bridge deck 1. The two upper anchor columns 5 are dispersedly arranged to support the bridge deck 1 from both sides, respectively, which can ensure the stability and reliability of the supporting structure of the bridge deck 1, thereby improving the device structure stability of the detector.

[0023] The infrared detector provided in this embodiment can significantly increase the length of the bridge leg by having two bridge deck layers 1 share the same common bridge leg 2, that is, two adjacent pixel elements in the column direction share the same common bridge leg 2, thereby significantly reducing the thermal conductivity and significantly improving the performance of the detector. Without affecting the performance of the detector, the width and spacing of the common bridge leg 2 can be adjusted, so that the bridge leg etching and film growth processes are not affected by the machine deviation within the effective redundancy range of the machine, thereby effectively improving the process uniformity, repeatability and controllability of the detector, thereby improving the product yield of the detector.

[0024] In the structure of the infrared detector described above, different detector performance index requirements can be met by flexibly changing the length and width of the common bridge leg 2.

[0025] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An infrared detector, comprising a plurality of bridge deck layers arranged in an array and a plurality of readout circuit interfaces arranged in a one-to-one correspondence, each of the readout circuit interfaces being connected to a readout circuit, characterized in that: It also includes multiple common bridge legs. Each of the common bridge legs is respectively connected to two adjacent bridge deck layers in the column direction through two upper anchor columns, and the common bridge legs are respectively electrically connected to two corresponding readout circuit interfaces through a lower connection structure; The common bridge leg is in a serpentine structure, and the upper connection structure composed of two corresponding upper anchor columns and the lower connection structure are respectively located at the head and tail sides of the common bridge leg; the common bridge leg is partially located directly below one of the connected bridge deck layers, and partially located directly below the other connected bridge deck layer; Every two rows are provided with one common bridge leg toward the adjacent bridge decks; The lower connection structure includes a lower anchor column and a metal connection layer, the metal connection layer is electrically connected to the corresponding two readout circuit interfaces respectively, and the lower anchor column is arranged on the upper surface of the metal connection layer and supports the corresponding common bridge leg.

2. The infrared detector according to claim 1, characterized in that: The two upper anchor columns connected to each bridge deck are respectively close to the two row ends of the bridge deck.

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