阅读说明：本技术 一种红外探测器及其制作方法 (Infrared detector and manufacturing method thereof ) 是由 康晓旭 唐晨晨 邱佳梦 于 2020-06-17 设计创作，主要内容包括：本发明公开了一种红外探测器,包括：衬底和红外微桥桥面,微桥桥面通过支撑和电连接柱悬设于衬底上,支撑和电连接柱为一个,设于微桥桥面的下方,使微桥桥面形成以支撑和电连接柱为中心的悬空结构,微桥桥面自下而上包括依次相连的下电极层、敏感层和上电极层,下电极层、敏感层和上电极层还通过向支撑和电连接柱中进行延伸而成为其结构组成部分；其中,下电极层和上电极层之间相隔离,并沿支撑和电连接柱向下引出,与衬底中设置的处理电路分别相连。本发明可减小敏感电阻的阻值,提升像元的均匀性和一致性,并能有效提升感光面积和填充因子,从而能够明显提高灵敏度和均匀性。本发明还公开了一种红外探测器制造方法。(The invention discloses an infrared detector, comprising: the infrared micro-bridge comprises a substrate and an infrared micro-bridge deck, wherein the micro-bridge deck is suspended on the substrate through a supporting and electric connecting column, the supporting and electric connecting column is one and is arranged below the micro-bridge deck, so that the micro-bridge deck forms a suspended structure taking the supporting and electric connecting column as a center, the micro-bridge deck comprises a lower electrode layer, a sensitive layer and an upper electrode layer which are sequentially connected from bottom to top, and the lower electrode layer, the sensitive layer and the upper electrode layer form a structural component part by extending into the supporting and electric connecting column; the lower electrode layer and the upper electrode layer are isolated from each other, led out downwards along the support and electric connection columns and respectively connected with a processing circuit arranged in the substrate. The invention can reduce the resistance value of the sensitive resistor, improve the uniformity and consistency of the pixel, and effectively improve the photosensitive area and the fill factor, thereby obviously improving the sensitivity and the uniformity. The invention also discloses a manufacturing method of the infrared detector.)

1. An infrared detector, comprising: the infrared micro-bridge comprises a substrate and an infrared micro-bridge deck, wherein the micro-bridge deck is suspended on the substrate through a supporting and electric connecting column, the supporting and electric connecting column is one and is arranged below the micro-bridge deck, so that the micro-bridge deck forms a suspended structure taking the supporting and electric connecting column as a center, the micro-bridge deck comprises a lower electrode layer, a sensitive layer and an upper electrode layer which are sequentially connected from bottom to top, and the lower electrode layer, the sensitive layer and the upper electrode layer form structural components by extending into the supporting and electric connecting column; the lower electrode layer and the upper electrode layer are isolated, led out downwards along the supporting and electric connecting columns and respectively connected with a processing circuit arranged in the substrate.

2. The infrared detector as claimed in claim 1, wherein the lower electrode layer and the upper electrode layer form a sleeved annular structure at the extending portion of the supporting and electrical connecting column, the substrate is correspondingly provided with a sleeved annular outer electrode and an inner electrode, the lower ends of the annular structures of the lower electrode layer and the upper electrode layer are respectively connected to the upper ends of the outer electrode and the inner electrode, and the lower ends of the outer electrode and the inner electrode are respectively connected to the processing circuit.

3. The infrared detector as claimed in claim 1 or 2, characterized in that said upper electrode layer comprises a first upper electrode layer on said sensitive layer and a second upper electrode layer on said first upper electrode layer, between which a spacer layer is provided, said spacer layer covering the ends of said first upper electrode layer, said sensitive layer and said lower electrode layer from outside said suspended structure, so that said first upper electrode layer and said second upper electrode layer are simultaneously isolated from said lower electrode layer, and said spacer layer also being a structural component part thereof by extending into said support and electrical connection column and isolating said second upper electrode layer from said lower electrode layer; the isolation layer forms an infrared window on the micro-bridge deck, extends downwards to enter the first upper electrode layer at a position of the micro-bridge deck close to the supporting and electric connecting column, separates an extending part of the first upper electrode layer in the supporting and electric connecting column from a part on the micro-bridge deck, and is connected with the first upper electrode layer through the window, so that the part of the first upper electrode layer on the micro-bridge deck is connected with a processing circuit arranged in the substrate through the second upper electrode layer.

4. The infrared detector according to claim 3, characterized in that said window is an annular opening interposed between said support and electrical connection column and the outside of said microbridge deck.

5. The infrared detector as set forth in claim 3, wherein a portion of said second upper electrode layer on said microbridge deck is of a flat layer structure.

6. The infrared detector as set forth in claim 1, wherein a reflective layer is further disposed on said substrate, and a resonant cavity is formed between said reflective layer and said microbridge deck.

7. The infrared detector as set forth in claim 1, wherein said lower electrode layer and said upper electrode layer material comprise TiN or Pt.

8. A manufacturing method of an infrared detector is characterized by comprising the following steps:

providing a substrate containing processing circuitry, forming a sacrificial layer on the substrate, forming support and electrical connection holes in the sacrificial layer; wherein the support and electrical connection hole is one;

depositing a lower electrode layer material, a sensitive layer material and an upper electrode layer material on the sacrificial layer in sequence, filling the lower electrode layer material, the sensitive layer material and the upper electrode layer material along the inner wall of the support and electric connection hole, patterning the materials, forming a support and electric connection column in the support and electric connection hole, and forming a lower electrode layer, a sensitive layer and an upper electrode layer which take the support and electric connection column as a center, so that the lower electrode layer is isolated from the upper electrode layer, and the lower electrode layer and the upper electrode layer are led out downwards along the support and electric connection column and are respectively connected with the processing circuit;

and removing the sacrificial layer by adopting a release process to form a micro-bridge deck connected with the substrate through the supporting and electric connecting column, wherein the micro-bridge deck comprises a lower electrode layer, a sensitive layer and an upper electrode layer which are sequentially connected, and a suspension structure taking the supporting and electric connecting column as a center is formed.

9. The method for manufacturing an infrared detector according to claim 8, further comprising the steps of: before forming the sacrificial layer, forming annular outer electrodes and annular inner electrodes which are sleeved on the substrate corresponding to the positions of the supporting holes and the electric connecting holes, respectively connecting the lower ends of the outer electrodes and the inner electrodes to the processing circuit, and respectively connecting the lower ends of the lower electrode layer material and the upper electrode layer material to the upper ends of the outer electrodes and the inner electrodes when filling the supporting holes and the electric connecting holes.

10. A method for fabricating an infrared detector according to claim 8 or 9, wherein the upper electrode layer comprises a first upper electrode layer and a second upper electrode layer, and the method comprises the steps of:

sequentially depositing a lower electrode layer material and a sensitive layer material on the sacrificial layer, filling the lower electrode layer material and the sensitive layer material along the inner wall of the supporting and electric connecting hole, patterning, removing part of the sensitive layer material and the lower electrode layer material on the bottom of the supporting and electric connecting hole, exposing the surface of the substrate, and forming a sensitive layer and a lower electrode layer;

depositing a first upper electrode layer material on the sensitive layer, filling the first upper electrode layer material along the inner wall of the support and electric connection hole, patterning, removing part of the first upper electrode layer material on the bottom of the support and electric connection hole to expose the surface of the substrate, and separating the first upper electrode layer material from the lower electrode layer and the substrate through the sensitive layer to form a first upper electrode layer;

forming an annular groove surrounding the support and electrical connection hole on the first upper electrode layer at a position close to the support and electrical connection hole, so that the part of the first upper electrode layer located in the support and electrical connection hole is isolated from the part located on the surface of the sensitive layer;

depositing an isolation layer material on the first upper electrode layer, filling the isolation layer material along the inner wall of the support and electric connection hole, filling the groove, patterning the isolation layer material, removing part of the isolation layer material on the bottom of the support and electric connection hole to expose the surface of the substrate, and removing part of the isolation layer material on the sensitive layer outside the support and electric connection hole to form an isolation layer with an infrared window;

depositing a second upper electrode layer material on the isolation layer, filling the second upper electrode layer material along the inner wall of the support and electric connection hole, connecting the second upper electrode layer material with the processing circuit by contacting the surface of the substrate, and connecting the second upper electrode layer material with the first upper electrode layer through the infrared window; and forming a second upper electrode layer after the second upper electrode layer material is flattened.

Technical Field

The invention relates to the technical field of semiconductor integrated circuits and sensors, in particular to an infrared detector with high sensitivity and high uniformity and a manufacturing method thereof.

Background

The traditional infrared MEMS detector product generally adopts a micro-bridge resonant cavity structure, and the sensitive resistance of the traditional infrared MEMS detector product is defined on the plane of the surface of a micro-bridge, namely the sensitive resistance of the traditional infrared MEMS detector product is defined by a plane electrode pattern on a sensitive layer.

Referring to fig. 1, fig. 1 shows a distribution of sensitive resistance electrodes of a conventional infrared MEMS detector. As shown in fig. 1, in the conventional infrared MEMS detector structure, a sensing layer is disposed on a plane of a microbridge surface, and a metal electrode is disposed on each of left and right ends of the sensing layer to form a sensing resistor structure in a horizontal direction. Wherein the size of the sensitive resistor is determined by the lateral length L of the sensitive layer between the two metal electrodes.

According to the resistivity relation formula:

R＝ρ×L/S

where R is resistance, ρ is resistivity, L is conductor length, and S is conductor area.

It can be seen that, at a certain thickness of the sensitive layer (determining the size of S), the size of the sensitive resistor is mainly limited by the transverse length L (the film pattern area of the sensitive layer) of the sensitive layer between the two metal electrodes.

In order to improve the in-plane and in-chip uniformity of the detector, the designer defines the pattern size of the microbridge plane as large as possible (i.e., the conductor length L in the above formula is long), which results in a relatively large resistance of the sensitive resistor. Meanwhile, the sensitive layer is a high-resistance material with high resistivity, so that the sensitive resistance is further high, and the signal is small under the same voltage.

Moreover, when the microbridge plane is formed, various patterning (photolithography/etching) processes performed on each film layer on the microbridge plane also cause a decrease in the uniformity of the sensitive resistance.

In addition, the conventional art causes a decrease in the packing factor of the product due to the use of a plurality of supporting and electrically connecting columns.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides an infrared detector and a manufacturing method thereof.

In order to achieve the purpose, the technical scheme of the invention is as follows:

an infrared detector, comprising: the infrared micro-bridge comprises a substrate and an infrared micro-bridge deck, wherein the micro-bridge deck is suspended on the substrate through a supporting and electric connecting column, the supporting and electric connecting column is one and is arranged below the micro-bridge deck, so that the micro-bridge deck forms a suspended structure taking the supporting and electric connecting column as a center, the micro-bridge deck comprises a lower electrode layer, a sensitive layer and an upper electrode layer which are sequentially connected from bottom to top, and the lower electrode layer, the sensitive layer and the upper electrode layer form structural components by extending into the supporting and electric connecting column; the lower electrode layer and the upper electrode layer are isolated, led out downwards along the supporting and electric connecting columns and respectively connected with a processing circuit arranged in the substrate.

Furthermore, the lower electrode layer and the upper electrode layer form a sleeved annular structure at the extending part of the support and electric connection column, the substrate is correspondingly provided with a sleeved annular outer electrode and an inner electrode, the lower ends of the annular structures of the lower electrode layer and the upper electrode layer are respectively connected with the upper ends of the outer electrode and the inner electrode, and the lower ends of the outer electrode and the inner electrode are respectively connected to the processing circuit.

Furthermore, the upper electrode layer comprises a first upper electrode layer positioned on the sensitive layer and a second upper electrode layer positioned on the first upper electrode layer, an isolation layer is arranged between the first upper electrode layer and the second upper electrode layer, and the isolation layer covers the ends of the first upper electrode layer, the sensitive layer and the lower electrode layer from the outside of the suspended structure, so that the first upper electrode layer and the second upper electrode layer are simultaneously isolated from the lower electrode layer, and meanwhile, the isolation layer also becomes a structural component part of the support and electrical connection column by extending into the support and electrical connection column and isolates the second upper electrode layer from the lower electrode layer; the isolation layer forms an infrared window on the micro-bridge deck, extends downwards to enter the first upper electrode layer at a position of the micro-bridge deck close to the supporting and electric connecting column, separates an extending part of the first upper electrode layer in the supporting and electric connecting column from a part on the micro-bridge deck, and is connected with the first upper electrode layer through the window, so that the part of the first upper electrode layer on the micro-bridge deck is connected with a processing circuit arranged in the substrate through the second upper electrode layer.

Further, the window is an annular opening between the support and electrical connection post and the outside of the microbridge deck.

Further, the part of the second upper electrode layer on the bridge deck of the micro-bridge is of a flat layer structure.

Furthermore, a reflecting layer is further arranged on the substrate, and a resonant cavity is formed between the reflecting layer and the microbridge bridge surface.

Further, the lower electrode layer and the upper electrode layer material comprise TiN or Pt.

A manufacturing method of an infrared detector comprises the following steps:

providing a substrate containing processing circuitry, forming a sacrificial layer on the substrate, forming support and electrical connection holes in the sacrificial layer; wherein the support and electrical connection hole is one;

depositing a lower electrode layer material, a sensitive layer material and an upper electrode layer material on the sacrificial layer in sequence, filling the lower electrode layer material, the sensitive layer material and the upper electrode layer material along the inner wall of the support and electric connection hole, patterning the materials, forming a support and electric connection column in the support and electric connection hole, and forming a lower electrode layer, a sensitive layer and an upper electrode layer which take the support and electric connection column as a center, so that the lower electrode layer is isolated from the upper electrode layer, and the lower electrode layer and the upper electrode layer are led out downwards along the support and electric connection column and are respectively connected with the processing circuit;

and removing the sacrificial layer by adopting a release process to form a micro-bridge deck connected with the substrate through the supporting and electric connecting column, wherein the micro-bridge deck comprises a lower electrode layer, a sensitive layer and an upper electrode layer which are sequentially connected, and a suspension structure taking the supporting and electric connecting column as a center is formed.

Further, the method also comprises the following steps: before forming the sacrificial layer, forming annular outer electrodes and annular inner electrodes which are sleeved on the substrate corresponding to the positions of the supporting holes and the electric connecting holes, respectively connecting the lower ends of the outer electrodes and the inner electrodes to the processing circuit, and respectively connecting the lower ends of the lower electrode layer material and the upper electrode layer material to the upper ends of the outer electrodes and the inner electrodes when filling the supporting holes and the electric connecting holes.

Further, the upper electrode layer comprises a first upper electrode layer and a second upper electrode layer, and the manufacturing method comprises the following steps:

sequentially depositing a lower electrode layer material and a sensitive layer material on the sacrificial layer, filling the lower electrode layer material and the sensitive layer material along the inner wall of the supporting and electric connecting hole, patterning, removing part of the sensitive layer material and the lower electrode layer material on the bottom of the supporting and electric connecting hole, exposing the surface of the substrate, and forming a sensitive layer and a lower electrode layer;

depositing a first upper electrode layer material on the sensitive layer, filling the first upper electrode layer material along the inner wall of the support and electric connection hole, patterning, removing part of the first upper electrode layer material on the bottom of the support and electric connection hole to expose the surface of the substrate, and separating the first upper electrode layer material from the lower electrode layer and the substrate through the sensitive layer to form a first upper electrode layer;

forming an annular groove surrounding the support and electrical connection hole on the first upper electrode layer at a position close to the support and electrical connection hole, so that the part of the first upper electrode layer located in the support and electrical connection hole is isolated from the part located on the surface of the sensitive layer;

depositing an isolation layer material on the first upper electrode layer, filling the isolation layer material along the inner wall of the support and electric connection hole, filling the groove, patterning the isolation layer material, removing part of the isolation layer material on the bottom of the support and electric connection hole to expose the surface of the substrate, and removing part of the isolation layer material on the sensitive layer outside the support and electric connection hole to form an isolation layer with an infrared window;

depositing a second upper electrode layer material on the isolation layer, filling the second upper electrode layer material along the inner wall of the support and electric connection hole, connecting the second upper electrode layer material with the processing circuit by contacting the surface of the substrate, and connecting the second upper electrode layer material with the first upper electrode layer through the infrared window; and forming a second upper electrode layer after the second upper electrode layer material is flattened.

According to the technical scheme, on one hand, the infrared detector structure based on the upper and lower distributed electrodes (namely the vertical sensitive resistor) is formed, and the current in the vertical direction is formed in the sensitive resistor, so that under the condition that the whole area of the microbridge structure is not changed (the area size of the microbridge is far larger than the thickness size of the microbridge), the resistance value of the sensitive resistor is only influenced by the thickness of the thin film, and the resistance value of the sensitive layer material is still smaller although the resistivity of the sensitive layer material is higher. Meanwhile, the infrared micro-bridge structure is formed by utilizing a planar process, so that the uniformity of the sensitive resistor is only influenced by the thickness of the film, and the larger uniformity difference caused by defining the size of the pattern by photoetching and etching is avoided, thereby improving the uniformity of the pixel. In addition, the surface area of the whole micro-bridge becomes a resistance area of the pixel, namely the size of the pattern is far larger than the size defined by plane photoetching and etching, so that the uniformity of the micro-bridge can be improved. In addition, a single supporting and electric connecting column structure is used, so that the photosensitive area and the filling factor are effectively improved, and the sensitivity and the uniformity can be obviously improved.

Drawings

Fig. 1 is a schematic diagram of a distribution form of sensitive resistance electrodes of a conventional infrared MEMS detector.

Fig. 2 is a schematic structural diagram of an infrared detector according to a preferred embodiment of the invention.

Fig. 3 is a schematic structural diagram of an infrared detector according to a second preferred embodiment of the invention.

Fig. 4 is a schematic structural view of a sleeved annular inner electrode and an outer electrode according to a preferred embodiment of the invention.

FIG. 5 is a schematic diagram of a distribution of the sensitive resistance electrodes of the present invention.

Detailed Description

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

In the following detailed description of the embodiments of the present invention, in order to clearly illustrate the structure of the present invention and to facilitate explanation, the structure shown in the drawings is not drawn to a general scale and is partially enlarged, deformed and simplified, so that the present invention should not be construed as limited thereto.

In the following detailed description of the present invention, please refer to fig. 2, fig. 2 is a schematic structural diagram of an infrared detector according to a first preferred embodiment of the present invention. As shown in fig. 2, an infrared detector of the present invention includes: the infrared micro-bridge comprises a substrate 1 and an infrared micro-bridge deck I arranged on the substrate 1. Wherein, the bridge deck I of the micro-bridge is suspended on the substrate 1 only through a supporting and electric connecting column II. The supporting and electric connecting column II is arranged below the micro-bridge deck I, so that the micro-bridge deck I forms a suspended structure taking the supporting and electric connecting column II as the center. The term "central" is used broadly herein to mean that it is not limited to a symmetrical configuration centered on the support and electrical connection post II, i.e., the microbridge deck I may be asymmetrically distributed over the support and electrical connection post II. A processing circuit 12 is provided in the substrate 1.

Please refer to fig. 2. The microbridge bridge deck I comprises a lower electrode layer 6, a sensitive layer 5 and an upper electrode layer 4 which are sequentially connected from bottom to top. The lower electrode layer 6, the sensitive layer 5 and the upper electrode layer 4 also form a structural component of the support and electrical connection stud ii by extending into the support and electrical connection stud ii. Thus, the lower electrode layer 6, the sensitive layer 5 and the upper electrode layer 4 respectively have a part located in the supporting and electrically connecting column II and a part (micro-bridge pixel structure) located on the micro-bridge deck I outside the supporting and electrically connecting column II, and the two parts are connected into a whole with each other.

The lower electrode layer 6 and the upper electrode layer 4 can be isolated by the sensitive layer 5. Wherein, the lower electrode layer 6 part and the upper electrode layer 4 part which are positioned in the supporting and electric connecting column II are led out downwards along the supporting and electric connecting column II and are respectively connected with a processing circuit 12 arranged in the substrate 1.

A separation layer 3 may also be provided between the sensitive layer 5 and the upper electrode layer 4. The isolating layer 3 likewise forms a structural component of the support and electrical connection post ii by extending into it. Meanwhile, the isolation layer 3 contacts the surface of the substrate 1 at the bottom of the support and electrical connection post ii, thereby separating the lower electrode layer 6 from the upper electrode layer 4. In addition, the isolation layer 3 also forms an infrared window on the micro-bridge deck I; the window may be an annular opening between the support and electrical connection post ii and the outside of the microbridge deck i. The upper electrode layer 4 can be connected to the sensitive layer 5 via an infrared window. The isolation layer 3 also covers the sensitive layer 5 and the end part of the lower electrode layer 6 from the outside of the suspension structure of the microbridge bridge deck I, so that the end part of the upper electrode layer 4 covered on the isolation layer 3 is isolated from the end part of the lower electrode layer 6.

Please refer to fig. 2. The lower electrode layer 6, the sensitive layer 5, the isolation layer 3 and the upper electrode layer 4 form a sleeved annular structure at the extension parts of the supporting and electric connecting columns II. Meanwhile, an annular outer electrode 10 and an inner electrode 11 are correspondingly arranged on the substrate 1.

Please refer to fig. 4. The outer electrode 10 and the inner electrode 11 may form a concentric ring structure on the substrate 1. Wherein, the inner electrode 11 can also form a solid column structure as shown in the figure; the space between the outer electrode 10 and the inner electrode 11 can be filled with a dielectric material.

Please refer to fig. 2 in combination with fig. 4. The lower ends of the annular structures of the lower electrode layer 6 and the upper electrode layer 4 are respectively connected with the upper ends of an outer electrode 10 and an inner electrode 11, and the lower ends of the outer electrode 10 and the inner electrode 11 are respectively connected to a processing circuit 12.

The center of the support and electrical connection post ii may be a hollow structure as shown. Alternatively, a solid structure may be formed by filling.

Further, a reflective layer 2 is also provided on the substrate 1; a resonant cavity 7 is formed between the reflecting layer 2 and the microbridge bridge surface I.

The material of the lower electrode layer 6 and the upper electrode layer 4 may include TiN or Pt or the like which is not damaged in the release process.

The substrate 1, the sensitive layer 5, the isolation layer 3, the reflective layer 2, the outer electrode 10, the inner electrode 11, etc. can be made of common materials.

Referring to fig. 5, the structural principle of the sensitive resistor of the present invention in fig. 2 is shown. As shown in fig. 5, unlike the horizontal electrode distribution form of the conventional sense resistor in fig. 1, the sense resistor of the present invention adopts an up-down electrode distribution form, that is, the upper electrode (upper electrode layer 4) and the lower electrode (lower electrode layer 6) are respectively located at the upper layer and the lower layer of the sense layer 5, so as to form a vertical current. At this time, the conductor length L in the resistivity formula is converted into the vertical thickness L of the sensitive layer 5 in the present invention, and the conductor area S is converted into the horizontal area S of the sensitive layer 5 in the present invention.

When the whole area of the microbridge structure is not changed (the area size of the microbridge is far larger than the thickness size of the microbridge), the resistance of the sensitive resistor is only influenced by the thickness of the film, so that a smaller resistance can be obtained although the resistivity of the material of the sensitive layer 5 is higher.

Meanwhile, in order to improve the uniformity of the sensitive resistor, the infrared micro-bridge deck I structure is formed by utilizing a planar process, namely, the lower electrode layer 6, the sensitive layer 5 and the upper electrode layer 4 which are positioned on the micro-bridge deck I are all in a flat layer structure by utilizing the planar process, and a graph is formed in the flat layer structure of the lower electrode layer 6, the sensitive layer 5 and the upper electrode layer 4 without adopting patterning processes such as photoetching/etching and the like, so that the uniformity of the sensitive resistor is only influenced by the thickness of a film and is not influenced by the conventional patterning processes such as photoetching/etching and the like.

The area size of the microbridge bridge deck I is generally 10-20 mu m in magnitude, and the area size is larger, so the process control in the aspect of the size is better, and the uniformity of a semiconductor film forming process is far better than that of a patterning process, so the uniformity can be better controlled, the uniformity of the sensitive resistor is greatly improved, and the optical characteristic of the resonant cavity 7 is effectively improved.

The infrared detector structure of the present invention shown in fig. 2 can be manufactured as follows.

First, a substrate 1 containing processing circuitry 12 is provided.

Then, a sleeved annular outer electrode 10 and inner electrode 11 are formed on the substrate 1 corresponding to the support and electrical connection post II through the processes of photoetching, etching, filling and the like, and the lower ends of the outer electrode 10 and the inner electrode 11 are respectively connected to a processing circuit 12.

Then, a material of the reflective layer 2 is deposited on the substrate 1, the material of the reflective layer 2 is patterned by photolithography, etching, and the like, electrical connection patterns (for example, annular electrical connection patterns which are provided in a nested manner) 8 and 9 are respectively formed at positions corresponding to the outer electrode 10 and the inner electrode 11, the electrical connection patterns 8 and 9 are respectively connected to upper ends of the outer electrode 10 and the inner electrode 11, and the reflective layer 2 which is independently provided is formed at both sides of the electrical connection patterns 8 and 9.

Then, a sacrificial layer (not shown) is formed on the substrate 1 and the reflective layer 2, and a support and electrical connection hole (referring to the position of the support and electrical connection post II) is formed in the sacrificial layer corresponding to the outer electrode 10 and the inner electrode 11 by photolithography and etching processes, thereby exposing the electrical connection patterns 8 and 9 on the surface of the substrate 1. The supporting and electric connecting holes are used for forming supporting and electric connecting columns II subsequently.

And then, sequentially depositing a lower electrode layer 6 material and a sensitive layer 5 material on the sacrificial layer, so that the lower electrode layer 6 material and the sensitive layer 5 material are filled along the inner wall of the supporting and electric connecting hole. And patterning the material of the lower electrode layer 6 and the material of the sensitive layer 5 by photoetching and etching, removing part of the material of the sensitive layer 5 and the material of the lower electrode layer 6 on the bottom of the supporting and electric connecting hole, so that the lower end of the material of the lower electrode layer 6 is connected with an electric connecting pattern 8 on a lower outer electrode 10, and is connected with a processing circuit 12 in the substrate 1 through the outer electrode 10, and an electric connecting pattern 9 on an inner electrode 11 is exposed to form the sensitive layer 5 and the lower electrode layer 6.

And then, depositing an isolating layer 3 material on the sensitive layer 5, filling the isolating layer 3 material along the inner wall of the supporting and electric connecting hole, patterning the isolating layer 3 material by photoetching and etching, removing part of the isolating layer 3 material on the bottom of the supporting and electric connecting hole, exposing the electric connecting pattern 9 on the inner electrode 11, removing part of the isolating layer 3 material on the surface of the sensitive layer 5 outside the supporting and electric connecting hole, and forming an infrared window, thereby forming the isolating layer 3 with the infrared window.

Next, an upper electrode layer 4 material is deposited on the spacer layer 3, the upper electrode layer 4 material is filled along the inner walls of the support and electrical connection holes, and the lower end of the upper electrode layer 4 material is connected to the electrical connection pattern 9 on the lower internal electrode 11, thereby being connected to the processing circuit 12 in the substrate 1 through the internal electrode 11. Meanwhile, the material of the upper electrode layer 4 is connected with the sensitive layer 5 through the infrared window to form the upper electrode layer 4. Thus, a support and electric connection column II structure consisting of the materials of the lower electrode layer 6, the sensitive layer 5, the isolation layer 3 and the upper electrode layer 4 is formed in the support and electric connection hole, and a micro-bridge deck I structure consisting of the materials of the lower electrode layer 6, the sensitive layer 5, the isolation layer 3 and the upper electrode layer 4 is formed on the surface of the sacrificial layer outside the support and electric connection hole.

And finally, removing the sacrificial layer by adopting a release process to form a micro-bridge deck I connected with the substrate 1 through a supporting and electric connecting column II and form a suspended structure of the micro-bridge deck I taking the supporting and electric connecting column II as the center.

In the following detailed description of the present invention, please refer to fig. 3, in which fig. 3 is a schematic structural diagram of an infrared detector according to a second preferred embodiment of the present invention. As shown in fig. 3, the difference from the first embodiment shown in fig. 2 is that in the second embodiment, the upper electrode layer 4 may include a first upper electrode layer 4-1 and a second upper electrode layer 4-2 on the sensitive layer 5, and the isolation layer 3 is disposed between the first upper electrode layer 4-1 and the second upper electrode layer 4-2.

The first upper electrode layer 4-1, the isolation layer 3 and the second upper electrode layer 4-2 are sequentially arranged on the sensitive layer 5 and extend into the supporting and electric connecting column II to form a structural component of the supporting and electric connecting column II together with the sensitive layer 5 and the lower electrode layer 6.

In the supporting and electric connecting column II, the lower end of the isolating layer 3 is abutted against the surface of the substrate 1 between the electric connecting pattern 8 on the outer electrode 10 and the electric connecting pattern 9 on the inner electrode 11, so that the second upper electrode layer 4-2 and the first upper electrode layer 4-1 are isolated from the lower electrode layer 6 at the same time; at the same time, the first upper electrode layer 4-1 is also isolated from the lower electrode layer 6 by the sensitive layer 5. The lower end of the lower electrode layer 6 is connected to the electrical connection pattern 8 of the lower external electrode 10, and the lower end of the second upper electrode layer 4-2 is connected to the electrical connection pattern 9 of the lower internal electrode 11.

On the bridge deck I of the microbridge, the isolation layer 3 covers the ends of the first upper electrode layer 4-1, the sensitive layer 5 and the lower electrode layer 6 from the outside of the suspended structure, so that the first upper electrode layer 4-1 and the second upper electrode layer 4-2 are isolated from the lower electrode layer 6 at the same time. Meanwhile, the isolation layer 3 is provided with an infrared window on the micro-bridge deck I, and the second upper electrode layer 4-2 is connected with the first upper electrode layer 4-1 below through the window. A groove 13 which surrounds the supporting and electric connecting column II and penetrates through the first upper electrode layer 4-1 is formed in the first upper electrode layer 4-1 at the position of the micro bridge deck I close to the supporting and electric connecting column II, the isolating layer 3 extends downwards into the first upper electrode layer 4-1 through the groove 13, and the extending part of the first upper electrode layer 4-1 in the supporting and electric connecting column II is isolated from the part on the micro bridge deck I. So that the portion of the first upper electrode layer 4-1 on the bridge deck i of the microbridge is connected to the processing circuit 12 provided in the substrate 1 through the second upper electrode layer 4-2 on the window.

Further, the portion of the second upper electrode layer 4-2 on the micro bridge deck i may be a flat layer structure.

The first upper electrode layer 4-1 and the second upper electrode layer 4-2 of the infrared detector structure of the present invention of fig. 3 described above can be manufactured by the following method.

After the lower electrode layer 6 and the sensitive layer 5 are formed, first upper electrode layer 4-1 material is deposited on the sensitive layer 5, the first upper electrode layer 4-1 material is filled along the inner wall of the supporting and electric connecting hole, the first upper electrode layer 4-1 material is patterned through photoetching and etching, the first upper electrode layer 4-1 material on the bottom of the supporting and electric connecting hole is removed, the electric connecting pattern 9 on the inner electrode 11 is exposed, and the first upper electrode layer 4-1 material is separated from the lower electrode layer 6 and the substrate 1 through the sensitive layer 5 to form the first upper electrode layer 4-1.

Next, an annular groove 13 is formed in the first upper electrode layer 4-1 outside the supporting and electrically connecting hole and near the supporting and electrically connecting hole, so that the portion of the first upper electrode layer 4-1 in the supporting and electrically connecting hole is isolated from the portion on the surface of the sensitive layer 5.

Then, depositing an isolation layer 3 material on the first upper electrode layer 4-1, filling the isolation layer 3 material along the inner wall of the support and electric connection hole, and filling the groove 13 at the same time; by photoetching and etching, the isolation layer 3 material is patterned, the isolation layer 3 material on the bottom of the supporting and electric connecting hole is removed, the lower end of the isolation layer 3 material is abutted against the surface of the substrate 1 and is positioned within the electric connecting pattern 8 on the outer electrode 10, the electric connecting pattern 9 on the inner electrode 11 is exposed, and part of the isolation layer 3 material above the sensitive layer 5 outside the supporting and electric connecting hole is removed to form an infrared window, so that the isolation layer 3 is formed. The infrared window may for example be located in a suitable position above the sensitive layer 5 between the trench 13 and the outside of the microbridge structure.

Next, a second upper electrode layer 4-2 material is deposited on the spacer layer 3, the second upper electrode layer 4-2 material is filled along the inner walls of the support and electrical connection holes, and the lower end of the second upper electrode layer 4-2 material is connected to the electrical connection pattern 9 on the lower internal electrode 11, thereby being connected to the processing circuitry 12 in the substrate 1 through the internal electrode 11. Meanwhile, the material of the second upper electrode layer 4-2 is connected with the first upper electrode layer 4-1 through the infrared window, and the second upper electrode layer 4-2 is formed after the material surface of the second upper electrode layer 4-2 is flattened. Thus, a support and electric connection column II structure consisting of the materials of the lower electrode layer 6, the sensitive layer 5, the first upper electrode layer 4-1, the isolation layer 3 and the second upper electrode layer 4-2 is formed in the support and electric connection hole; meanwhile, a micro-bridge deck I structure composed of materials of a lower electrode layer 6, a sensitive layer 5, a first upper electrode layer 4-1, an isolation layer 3 and a second upper electrode layer 4-2 is formed on the surface of the sacrificial layer outside the supporting and electric connecting column II.

The above description is only a preferred embodiment of the present invention, and the embodiments are not intended to limit the scope of the present invention, so that all equivalent structural changes made by using the contents of the specification and the drawings of the present invention should be included in the scope of the present invention.