阅读说明：本技术 一种红外探测器及其制备方法 (Infrared detector and preparation method thereof ) 是由 翟光杰 潘辉 武佩 于 2021-02-01 设计创作，主要内容包括：本公开涉及一种红外探测器及其制备方法,红外探测器包括衬底以及位于衬底上的介质层、电极层和热敏层,电极层位于介质层和热敏层之间,介质层位于电极层临近衬底的一侧,电极层与热敏层接触设置；红外探测器包括多个矩阵排列的红外探测器像元,红外探测器像元包括吸收板结构、至少两个微桥柱和至少两个梁结构,吸收板结构通过对应的梁结构连接至对应的微桥柱；热敏层覆盖吸收板结构和梁结构所在区域；其中,构成热敏层的材料包括非晶硅、非晶碳、非晶锗或非晶硅锗中的一种或几种；构成电极层的材料至少包括钛。通过本公开的技术方案,降低了红外探测器的热响应时间,提高了红外探测器的红外响应率。(The infrared detector comprises a substrate, and a dielectric layer, an electrode layer and a heat-sensitive layer which are arranged on the substrate, wherein the electrode layer is arranged between the dielectric layer and the heat-sensitive layer; the infrared detector comprises a plurality of infrared detector pixels arranged in a matrix, each infrared detector pixel comprises an absorption plate structure, at least two micro-bridge columns and at least two beam structures, and the absorption plate structures are connected to the corresponding micro-bridge columns through the corresponding beam structures; the heat-sensitive layer covers the area where the absorption plate structure and the beam structure are located; wherein, the material for forming the thermosensitive layer comprises one or more of amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium; the material constituting the electrode layer includes at least titanium. Through the technical scheme, the thermal response time of the infrared detector is shortened, and the infrared response rate of the infrared detector is improved.)

1. An infrared detector, comprising:

the electrode layer is positioned between the dielectric layer and the heat-sensitive layer, the dielectric layer is positioned on one side of the electrode layer close to the substrate, and the electrode layer is arranged in contact with the heat-sensitive layer;

the infrared detector comprises a plurality of infrared detector pixels arranged in a matrix, each infrared detector pixel comprises an absorption plate structure, at least two micro-bridge columns and at least two beam structures, and the absorption plate structures are connected to the corresponding micro-bridge columns through the corresponding beam structures;

the heat-sensitive layer covers the areas where the absorption plate structure and the beam structure are located; wherein, the material for forming the thermosensitive layer comprises one or more of amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium;

the material constituting the electrode layer includes at least titanium.

2. The infrared detector according to claim 1, wherein a material constituting the electrode layer further comprises one or more of titanium nitride, tantalum, or tantalum nitride;

the dielectric layer is made of one or more of amorphous silicon, amorphous carbon, amorphous germanium, amorphous silicon germanium or aluminum oxide.

3. The infrared detector as set forth in claim 1, wherein the material comprising the sacrificial layer between the substrate and the dielectric layer comprises silicon oxide.

4. The infrared detector of claim 1, further comprising:

the reflecting layer is arranged on the substrate in a contact mode, and the material forming the reflecting layer comprises one or more of aluminum, copper, titanium or tungsten.

5. The infrared detector of claim 4, further comprising:

and the protective layer is positioned on the reflecting layer and corresponds to the position of the micro-bridge column, and the electrode layer is electrically connected with the reflecting layer through a through hole penetrating through the protective layer and the dielectric layer.

6. The infrared detector as set forth in claim 5, wherein said protective layer is made of a material comprising one or more of silicon nitride, silicon carbide, aluminum oxide, silicon, or amorphous carbon.

7. The preparation method of the infrared detector is characterized in that the infrared detector comprises a plurality of infrared detector pixels arranged in a matrix, each infrared detector pixel comprises an absorption plate structure, at least two micro-bridge columns and at least two beam structures, and the absorption plate structure is connected to the corresponding micro-bridge columns through the corresponding beam structures;

the preparation method of the infrared detector comprises the following steps:

forming a sacrificial layer on a substrate;

forming a patterned dielectric layer on the sacrificial layer; forming a patterned structure on the dielectric layer corresponding to the micro-bridge pillar;

forming a patterned electrode layer on the patterned dielectric layer; the electrode layer forms a patterned structure corresponding to the absorption plate structure and the beam structure, and the material for forming the electrode layer at least comprises titanium;

forming a whole-surface heat-sensitive layer on the patterned electrode layer, and etching the heat-sensitive layer and the dielectric layer to form the absorption plate structure and the beam structure; the heat-sensitive layer forms a patterned structure corresponding to the absorption plate structure and the beam structure, the dielectric layer forms a patterned structure corresponding to the absorption plate structure and the beam structure, and the material forming the heat-sensitive layer comprises one or more of amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium;

and releasing the sacrificial layer.

8. The method of claim 7, wherein forming a patterned electrode layer on the patterned dielectric layer comprises:

forming a whole electrode layer on the patterned dielectric layer;

and etching the electrode layer corresponding to the position of the absorption plate structure and the position of the beam structure to form the patterned electrode layer.

9. The method of claim 7, further comprising, before forming the sacrificial layer on the substrate:

forming a patterned reflective layer on the substrate; wherein, the material for forming the reflecting layer comprises one or more of aluminum, copper, titanium or tungsten;

forming a patterned protective layer on the patterned reflective layer; wherein, the material for forming the protective layer comprises one or more of silicon nitride, silicon carbide, aluminum oxide, silicon or amorphous carbon;

forming a patterned sacrificial layer on the patterned protective layer; and the electrode layer is electrically connected with the reflecting layer through a through hole penetrating through the protective layer and the dielectric layer corresponding to the position of the micro-bridge column.

10. The method of claim 7, wherein a material constituting the sacrificial layer includes silicon oxide;

the releasing the sacrificial layer includes:

releasing the sacrificial layer using hydrogen fluoride gas.

Technical Field

The disclosure relates to the technical field of infrared detection, in particular to an infrared detector and a preparation method thereof.

Background

The non-contact infrared detector comprises a non-contact temperature measuring sensor, for example, and the detection principle is that the infrared detector converts an infrared radiation signal emitted by a target object to be detected into a thermal signal, the thermal signal is converted into an electric signal through a detector sensitive element, the electric signal is processed and output through a circuit chip, and the infrared detector realizes an infrared detection function.

Infrared detector includes absorbing plate structure and beam structure, absorbing plate structure and beam structure's performance direct influence infrared detector's thermal response performance and detection performance, the absorbing plate structure that generally corresponds infrared detector all needs the preparation solitary passivation layer to electrode layer in the protection absorbing plate structure is not by oxidation or overlook, but the setting of passivation rete can lead to the thickness increase of infrared detector absorbing plate structure, and then leads to infrared detector's thermal response time to increase, influences infrared detector's infrared detection performance.

Disclosure of Invention

In order to solve the technical problems or at least partially solve the technical problems, the present disclosure provides an infrared detector and a method for manufacturing the same, which reduces a thermal response time of the infrared detector and improves an infrared response rate of the infrared detector.

In a first aspect, the present disclosure provides an infrared detector comprising:

the electrode layer is positioned between the dielectric layer and the heat-sensitive layer, the dielectric layer is positioned on one side of the electrode layer close to the substrate, and the electrode layer is arranged in contact with the heat-sensitive layer;

the infrared detector comprises a plurality of infrared detector pixels arranged in a matrix, each infrared detector pixel comprises an absorption plate structure, at least two micro-bridge columns and at least two beam structures, and the absorption plate structures are connected to the corresponding micro-bridge columns through the corresponding beam structures;

the heat-sensitive layer covers the areas where the absorption plate structure and the beam structure are located; wherein, the material for forming the thermosensitive layer comprises one or more of amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium;

the material constituting the electrode layer includes at least titanium.

Optionally, the material forming the electrode layer further comprises one or more of titanium nitride, tantalum or tantalum nitride;

the dielectric layer is made of one or more of amorphous silicon, amorphous carbon, amorphous germanium, amorphous silicon germanium or aluminum oxide.

Optionally, the material forming the sacrificial layer between the substrate and the dielectric layer includes silicon oxide.

Optionally, the infrared detector further comprises:

the reflecting layer is arranged on the substrate in a contact mode, and the material forming the reflecting layer comprises one or more of aluminum, copper, titanium or tungsten.

Optionally, the infrared detector further comprises:

and the protective layer is positioned on the reflecting layer and corresponds to the position of the micro-bridge column, and the electrode layer is electrically connected with the reflecting layer through a through hole penetrating through the protective layer and the dielectric layer.

Optionally, the material constituting the protective layer includes one or more of silicon nitride, silicon carbide, aluminum oxide, silicon, or amorphous carbon.

In a second aspect, the present disclosure provides a method for manufacturing an infrared detector, where the infrared detector includes a plurality of infrared detector pixels arranged in a matrix, where the infrared detector pixels include an absorber plate structure, at least two micro-bridge columns, and at least two beam structures, and the absorber plate structure is connected to the corresponding micro-bridge columns through the corresponding beam structures;

the preparation method of the infrared detector comprises the following steps:

forming a sacrificial layer on a substrate;

forming a patterned dielectric layer on the sacrificial layer; forming a patterned structure on the dielectric layer corresponding to the micro-bridge pillar;

forming a patterned electrode layer on the patterned dielectric layer; the electrode layer forms a patterned structure corresponding to the absorption plate structure and the beam structure, and the material for forming the electrode layer at least comprises titanium;

forming a whole-surface heat-sensitive layer on the patterned electrode layer, and etching the heat-sensitive layer and the dielectric layer to form the absorption plate structure and the beam structure; the heat-sensitive layer forms a patterned structure corresponding to the absorption plate structure and the beam structure, the dielectric layer forms a patterned structure corresponding to the absorption plate structure and the beam structure, and the material forming the heat-sensitive layer comprises one or more of amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium;

and releasing the sacrificial layer.

Optionally, forming a patterned electrode layer on the patterned dielectric layer includes:

forming a whole electrode layer on the patterned dielectric layer;

and etching the electrode layer corresponding to the position of the absorption plate structure and the position of the beam structure to form the patterned electrode layer.

Optionally, before forming the sacrificial layer on the substrate, the method further includes:

forming a patterned reflective layer on the substrate; wherein, the material for forming the reflecting layer comprises one or more of aluminum, copper, titanium or tungsten;

forming a patterned protective layer on the patterned reflective layer; wherein, the material for forming the protective layer comprises one or more of silicon nitride, silicon carbide, aluminum oxide, silicon or amorphous carbon;

forming a patterned sacrificial layer on the patterned protective layer; and the electrode layer is electrically connected with the reflecting layer through a through hole penetrating through the protective layer and the dielectric layer corresponding to the position of the micro-bridge column.

Optionally, the material constituting the sacrificial layer comprises silicon oxide;

the releasing the sacrificial layer includes:

releasing the sacrificial layer using hydrogen fluoride gas.

Compared with the prior art, the technical scheme provided by the embodiment of the disclosure has the following advantages:

the infrared detector provided by the embodiment of the disclosure comprises a substrate, and a dielectric layer, an electrode layer and a heat-sensitive layer which are arranged on the substrate, wherein the electrode layer is arranged between the dielectric layer and the heat-sensitive layer; the infrared detector comprises a plurality of infrared detector pixels arranged in a matrix, each infrared detector pixel comprises an absorption plate structure, at least two micro-bridge columns and at least two beam structures, and the absorption plate structures are connected to the corresponding micro-bridge columns through the corresponding beam structures; the heat-sensitive layer covers the area where the absorption plate structure and the beam structure are located, and the material forming the heat-sensitive layer comprises one or more of amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium; the material constituting the electrode layer includes at least titanium. From this, set up the electrode layer and be located the one side that the substrate is close to the heat-sensitive layer, need not to make extra passivation layer, only dielectric layer, electrode layer and heat-sensitive layer on the absorbing plate structure have reduced the thickness of absorbing plate structure, and then have reduced the heat capacity of absorbing plate structure, have reduced infrared detector's thermal response time. In addition, the thermosensitive layer made of amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium and other materials also covers the area where the beam structure is located, so that the thermal conductivity of the beam structure is favorably reduced, and the infrared response rate of the infrared detector is further improved. In addition, the absorption plate structure and the beam structure comprise the thermosensitive layers made of the same material, so that the manufacturing process of the infrared detector is simplified, and the manufacturing yield of the infrared detector is improved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and together with the description, serve to explain the principles of the disclosure.

In order to more clearly illustrate the embodiments or technical solutions in the prior art of the present disclosure, the drawings used in the description of the embodiments or prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive exercise.

Fig. 1 is a schematic perspective view of an infrared detector according to an embodiment of the present disclosure;

fig. 2 is a schematic perspective structure diagram of an infrared detector pixel provided in an embodiment of the present disclosure;

fig. 3 is a schematic cross-sectional structure diagram of an infrared detector pixel provided in an embodiment of the present disclosure;

fig. 4 is a schematic top view of an electrode layer corresponding to an absorption plate structure according to an embodiment of the disclosure;

fig. 5 is a schematic flow chart illustrating a method for manufacturing an infrared detector according to an embodiment of the present disclosure;

fig. 6-12 are schematic cross-sectional structures corresponding to steps of a method for manufacturing an infrared detector, respectively.

Detailed Description

In order that the above objects, features and advantages of the present disclosure may be more clearly understood, aspects of the present disclosure will be further described below. It should be noted that the embodiments and features of the embodiments of the present disclosure may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure, but the present disclosure may be practiced in other ways than those described herein; it is to be understood that the embodiments disclosed in the specification are only a few embodiments of the present disclosure, and not all embodiments.

Fig. 1 is a schematic perspective structure diagram of an infrared detector provided in an embodiment of the present disclosure, fig. 2 is a schematic perspective structure diagram of an infrared detector pixel provided in an embodiment of the present disclosure, and fig. 3 is a schematic sectional structure diagram of an infrared detector pixel provided in an embodiment of the present disclosure. With reference to fig. 1 to 3, the infrared detector includes a substrate 1, and a dielectric layer 3, an electrode layer 4 and a heat sensitive layer 2 on the substrate 1, wherein the electrode layer 4 is located between the dielectric layer 3 and the heat sensitive layer 2, the dielectric layer 3 is located on one side of the electrode layer 4 close to the substrate 1, and the electrode layer 4 is in contact with the heat sensitive layer 2. The infrared detector comprises a plurality of infrared detector pixels 100 which are arranged in a matrix, each infrared detector pixel 100 comprises an absorption plate structure 6, at least two micro-bridge columns 7 and at least two beam structures 8, and the absorption plate structures 6 are connected to the corresponding micro-bridge columns 7 through the corresponding beam structures 8.

For example, fig. 2 illustrates that the infrared detector pixel 100 includes four micro-bridge pillars 7 and two beam structures 8, and the specific number of the micro-bridge pillars 7 and the beam structures 8 included in the infrared detector pixel 100 is not limited in the embodiment of the present disclosure, for example, the number of the micro-bridge pillars 7 in the infrared detector pixel 100 may also be two, and the number of the beam structures 8 may also be four.

Specifically, be provided with the readout circuit in the substrate 1, the readout circuit is used for realizing the collection of infrared detection signal of telecommunication and the processing of data, micro-bridge post 7 structure for example can be hollow column structure, micro-bridge post 7 structure is located substrate 1 for supporting infrared detector's beam structure 8 and absorption plate structure 6 after sacrificial layer 9 on substrate 1 releases, absorption plate structure 6 is connected to corresponding micro-bridge post 7 through corresponding beam structure 8, and micro-bridge post 7 structure and the 8 overlap joints of beam structure and then realize the support to absorption plate structure 6 promptly.

Specifically, the thermosensitive layer 2 is used for converting an infrared temperature detection signal into an infrared detection electrical signal, the electrode layer 4 is used for transmitting the infrared detection electrical signal converted by the thermosensitive layer 2 to the substrate 11 through the beam structures 8 on the left and right sides, and fig. 4 is a schematic view of a top view structure of the electrode layer corresponding to the absorption plate structure provided by the embodiment of the present disclosure. Referring to fig. 1 to 4, two electrodes 41 and 42 are disposed at positions of the electrode layer 4 corresponding to the absorption plate structure 6, the two electrodes 41 and 42 are respectively connected to the beam structures 8 at the left and right sides, the two electrodes 41 and 42 respectively transmit positive and negative signals of the infrared detection electrical signal, that is, the two beam structures 8 respectively transmit positive and negative signals of the infrared detection electrical signal, and the readout circuit in the substrate 1 implements non-contact infrared temperature detection by analyzing the acquired infrared detection electrical signal.

Illustratively, the material forming the electrode layer 4 may be at least titanium, and may further include one or more of titanium nitride, tantalum, or tantalum nitride, and the material forming the dielectric layer 3 may be one or more of amorphous silicon, amorphous carbon, amorphous germanium, amorphous silicon germanium, or aluminum oxide.

With reference to fig. 1 to 4, the thermal sensitive layer 2 is disposed to cover the area where the absorber plate structure 6 and the beam structure 8 are located, and the material constituting the thermal sensitive layer 2 includes one or more of amorphous silicon, amorphous carbon, amorphous germanium, or amorphous silicon germanium.

The performance direct influence infrared detector's of absorbing plate structure and beam structure thermal response performance among the infrared detector, the absorbing plate structure that generally corresponds infrared detector all needs to make solitary passivation layer to electrode layer in the protection absorbing plate structure is not by oxidation or overlook, but the setting of passivation rete can lead to the thickness increase of infrared detector absorbing plate structure, and then leads to infrared detector's thermal response time to increase, influences infrared detector's infrared detection performance.

The embodiment of the disclosure further provides that the electrode layer 4 is located on one side of the heat sensitive layer 2 close to the substrate 1, an additional passivation layer is not required to be manufactured, and only the dielectric layer 3, the electrode layer 4 and the heat sensitive layer 2 are arranged on the absorption plate structure 6, so that the thickness of the absorption plate structure 6 is reduced, the heat capacity of the absorption plate structure 6 is further reduced, and the thermal response time of the infrared detector is reduced. In addition, the material forming the thermosensitive layer 2 includes one or more of amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium, that is, the thermosensitive layer 2 formed by the amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium and other materials is arranged to cover the area where the beam structure 8 is located, so that the amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium and other materials are used as the thermosensitive material, the amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium and other materials in the beam structure 8 can effectively reduce the thermal conductivity of the beam structure 8, and the thermal response rate of the infrared detector is improved. In addition, the absorption plate structure 6 and the beam structure 8 comprise the thermosensitive layers made of the same material, so that the manufacturing process of the infrared detector is simplified, and the manufacturing yield of the infrared detector is improved.

At present, infrared detectors are detector chip structures formed by CMOS circuits and MEMS structures, the process compatibility is not high, the productivity is low, the yield is low, the cost is high, the CMOS process is utilized to complete the circuits and the sensor structures together, and therefore the integrated infrared detector chip is the future development direction. Alternatively, in conjunction with fig. 1 to 4, it may be provided that the material constituting the sacrificial layer 9 between the substrate 1 and the dielectric layer 3 comprises silicon oxide. Specifically, the silicon oxide is used as the material of the sacrificial layer 9 between the substrate 1 and the dielectric layer 3, which is beneficial to realizing the CMOS process flow sheet of the readout circuit in the substrate 1 and the whole infrared detector, i.e. the infrared detector can be prepared by adopting the CMOS process, and an integrated infrared detector can be formed by utilizing the CMOS process, so that the preparation yield of the infrared detector is effectively improved, and the preparation cost of the infrared detector is reduced. In addition, the material forming the electrode layer 4 at least comprises titanium, and can also comprise one or more of titanium nitride, tantalum or tantalum nitride, and the etching selection of the materials of titanium, titanium nitride, tantalum or tantalum nitride and the like and silicon oxide is poor, so that the dielectric layer 3 is arranged between the electrode layer 4 and the sacrificial layer 9, the material forming the dielectric layer 3 comprises one or more of amorphous silicon, amorphous carbon, amorphous germanium, amorphous silicon germanium or aluminum oxide, and the silicon oxide has a good selective etching ratio with the materials of amorphous silicon, amorphous carbon, amorphous germanium, amorphous silicon germanium or aluminum oxide and the like, which is beneficial for the release of the sacrificial layer 9 formed by silicon oxide to form a released hollow structure, thereby avoiding the release process of the sacrificial layer 9 from influencing other film layers in the infrared detector, and optimizing the infrared detection performance of the infrared detector.

It should be noted that fig. 3 exemplarily shows the sacrificial layer 9 in the infrared detector for explaining a specific structure of the infrared detector, and in the finally formed infrared detector product, the sacrificial layer 9 is released, that is, the sacrificial layer 9 is not present.

Optionally, in conjunction with fig. 1 to 4, the infrared detector may further include a reflective layer 10 on the substrate 1, the reflective layer 10 being disposed in contact with the substrate 1. Specifically, the infrared detector further comprises a reflecting layer 10 located on the substrate 1, the reflecting layer 10 can reflect infrared rays irradiated to the reflecting layer 10 to the absorption plate structure 6 in the infrared detector pixel 100, and secondary absorption of the infrared rays is realized by matching with a resonant cavity formed by the infrared detector pixel 100, so that the infrared absorption rate of the infrared detector pixel 100 is improved.

Illustratively, the material constituting the reflective layer 10 may be configured to include one or more of aluminum, copper, titanium, or tungsten, and the reflective layer 10 made of the aluminum, copper, titanium, or tungsten material may be configured to implement the absorption plate structure 6 that reflects infrared rays irradiated to the reflective layer 10 into the infrared detector pixel 100 to improve the infrared absorption rate of the infrared detector pixel 100. In addition, the silicon oxide has a good selective etching ratio with aluminum, copper, titanium or tungsten, and the materials forming the reflecting layer 10 include one or more of aluminum, copper, titanium or tungsten, so that the release of the sacrificial layer 9 formed by the silicon oxide is facilitated to form a released hollow structure, the influence of the release process of the sacrificial layer 9 on other film layers in the infrared detector is avoided, and the infrared detection performance of the infrared detector is optimized.

Optionally, with reference to fig. 1 to 4, the infrared detector may further include a protective layer 11 on the reflective layer 10, where the electrode layer 4 is electrically connected to the reflective layer 10 through a through hole penetrating through the protective layer 11 and the dielectric layer 3 corresponding to the location of the micro-bridge pillar 7. Specifically, the protective layer 11 is formed with porous structure corresponding to the position of the micro-bridge column 7, the dielectric layer 3 is formed with porous structure corresponding to the position of the micro-bridge column 7, so as to realize that the electrode layer 4 is electrically connected with the reflecting layer 10 through the through hole penetrating through the protective layer 11 and the dielectric layer 3, and further realize that the infrared detection electric signal converted by the thermosensitive layer 2 is transmitted to the electrode layer 4, and is transmitted to the reflecting layer 10 through the structure of the micro-bridge column 7 via the beam structures 8 on the left and right sides, the part of the reflecting layer 10 electrically connected with the electrode layer 4 serves as a connecting disc-shaped structure, and further transmit the infrared detection electric signal to the reading circuit in the substrate 1, and the reading circuit performs analysis of the infrared detection electric signal and processing of related data, so as to realize the infrared detection function of the infrared detector. In addition, the protective layer 11 can protect the reflective layer 10 serving as the connecting disk structure from oxidation and corrosion after the sacrificial layer 9 is released.

Illustratively, the material that may be provided to form the protective layer 11 includes one or more of silicon nitride, silicon carbide, aluminum oxide, silicon, or amorphous carbon. Specifically, the protective layer 11 made of a material such as silicon nitride, silicon carbide, aluminum oxide, silicon, or amorphous carbon can effectively protect the reflective layer 10 serving as the connecting disk structure after the sacrificial layer 9 is released. In addition, the silicon oxide has a good selective etching ratio with materials such as silicon nitride, silicon carbide, aluminum oxide, silicon or amorphous carbon, and the like, and the materials forming the protective layer 11 include one or more of silicon nitride, silicon carbide, aluminum oxide, silicon or amorphous carbon, so that the release of the sacrificial layer 9 formed by the silicon oxide is facilitated to form a released hollow structure, the influence of the release process of the sacrificial layer 9 on other film layers in the infrared detector is avoided, and the infrared detection performance of the infrared detector is optimized.

The electrode layer 4 is arranged on one side, close to the substrate 1, of the heat sensitive layer 2, an extra passivation layer does not need to be manufactured, only the dielectric layer 3, the electrode layer 4 and the heat sensitive layer 2 are arranged on the absorption plate structure 6, the thickness of the absorption plate structure 6 is reduced, the heat capacity of the absorption plate structure 6 is further reduced, and the thermal response time of the infrared detector is shortened. In addition, the thermosensitive layer 2 made of amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium and other materials also covers the area where the beam structure 8 is located, so that the thermal conductivity of the beam structure 8 is favorably reduced, and the infrared response rate of the infrared detector is further improved. In addition, the absorption plate structure 6 and the beam structure 8 comprise the thermosensitive layer 2 made of the same material, so that the manufacturing process of the infrared detector is simplified, and the manufacturing yield of the infrared detector is improved.

The embodiment of the disclosure also provides a preparation method of the infrared detector, and fig. 5 is a schematic flow chart of the preparation method of the infrared detector provided by the embodiment of the disclosure. The method of manufacturing the infrared detector may be used to manufacture the infrared detector as in the above embodiments. As shown in fig. 5, the method for manufacturing the infrared detector includes:

and S110, forming a sacrificial layer on the substrate.

Specifically, before forming the sacrificial layer on the substrate 1, as shown in fig. 6, a patterned reflective layer 10 is formed on the substrate 1, the material forming the reflective layer 10 may include one or more of aluminum, copper, titanium, or tungsten, and the entire reflective layer 10 may be formed first and then etched to form a corresponding pattern. As shown in fig. 7, a patterned protection layer 11 is formed on the patterned reflective layer 10, the material constituting the protection layer 11 may include one or more of silicon nitride, silicon carbide, aluminum oxide, silicon, or amorphous carbon, and the entire protection layer 11 may be formed first, and then etched to form a corresponding pattern, so that the protection layer 11 forms a via hole 110 corresponding to the position of the micro-bridge pillar, so as to expose the reflective layer 10 serving as a connecting disk structure. As shown in fig. 8, a patterned sacrificial layer 9 is formed on the patterned protection layer 11, and the entire sacrificial layer 9 may be formed first, and then etched to form a corresponding pattern, so that a via hole 90 is formed at a position of the sacrificial layer 9 corresponding to the micro-bridge pillar, so as to expose the reflective layer 10 serving as the connecting disk structure.

S120, forming a patterned dielectric layer on the sacrificial layer; and forming a patterned structure at the position of the dielectric layer corresponding to the micro-bridge pillar.

Specifically, as shown in fig. 9, the patterned dielectric layer 3 is formed on the sacrificial layer 9, the entire dielectric layer 3 may be formed on the sacrificial layer 9, and then the dielectric layer 3 is etched corresponding to the position of the micro-bridge pillar 7 to form the patterned dielectric layer 3, for example, the dielectric layer 3 may be etched at the bottom of the micro-bridge pillar 7 to form the via 30. Illustratively, the material constituting the dielectric layer 3 may be set to include one or more of amorphous silicon, amorphous carbon, amorphous germanium, amorphous silicon germanium, or aluminum oxide.

S130, forming a patterned electrode layer on the patterned dielectric layer; the electrode layer forms a patterned structure corresponding to the absorption plate structure and the beam structure, and the material forming the electrode layer at least comprises titanium.

Specifically, with reference to fig. 3 and fig. 10, a patterned electrode layer 4 is formed on the patterned dielectric layer 3, the material constituting the electrode layer 4 at least includes titanium, and may further include one or more of titanium nitride, tantalum, or tantalum nitride, the electrode layer 4 on the entire surface may be formed on the patterned dielectric layer 3, and the electrode layer 4 is etched corresponding to the position of the absorber plate structure 6 and the position of the beam structure 8 to form the patterned electrode layer 4, so that the electrode layer 4 forms a patterned structure corresponding to the absorber plate structure 6 and the beam structure 8. In addition, the electrode layer 4 is electrically connected with the reflecting layer 10 through a through hole penetrating through the protective layer 11 and the dielectric layer 3 corresponding to the position of the micro-bridge pillar 7.

S140, forming a whole-surface heat-sensitive layer on the patterned electrode layer, and etching the heat-sensitive layer and the dielectric layer to form an absorption plate structure and a beam structure; the heat-sensitive layer forms a patterned structure corresponding to the absorbing plate structure and the beam structure, the dielectric layer forms a patterned structure corresponding to the absorbing plate structure and the beam structure, and the material forming the heat-sensitive layer comprises one or more of amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium.

Specifically, with reference to fig. 3 and 11, a whole thermal sensitive layer 2 is formed on a patterned electrode layer 4, the thermal sensitive layer 2 and a dielectric layer 3 are etched to form an absorbing plate structure 6 and a beam structure 8, the etched thermal sensitive layer 2 forms a patterned structure corresponding to the absorbing plate structure 6 and the beam structure 8, the etched dielectric layer 3 forms a patterned structure corresponding to the absorbing plate structure 6 and the beam structure 8, and a material constituting the thermal sensitive layer 2 includes one or more of amorphous silicon, amorphous carbon, amorphous germanium, or amorphous silicon germanium.

From this, realized that electrode layer 4 is located the one side that heat sensitive layer 2 closes to substrate 1, need not to make extra passivation layer, only dielectric layer 3, electrode layer 4 and heat sensitive layer 2 on the absorption plate structure 6 have reduced absorption plate structure 6's thickness, and then have reduced absorption plate structure 6's heat capacity, have reduced infrared detector's thermal response time. In addition, the thermosensitive layer 2 made of amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium and other materials also covers the area where the beam structure 8 is located, so that the thermal conductivity of the beam structure 8 is favorably reduced, and the infrared response rate of the infrared detector is further improved. In addition, the absorption plate structure 6 and the beam structure 8 comprise the thermosensitive layer 2 made of the same material, so that the manufacturing process of the infrared detector is simplified, and the manufacturing yield of the infrared detector is improved.

And S150, releasing the sacrificial layer.

Specifically, as shown in fig. 12, the material constituting the sacrifice layer 9 includes silicon oxide, and the sacrifice layer 9 can be released by hydrogen fluoride gas. The material forming the reflecting layer 10 comprises one or more of aluminum, copper, titanium or tungsten, the material forming the protective layer 11 comprises one or more of silicon nitride, silicon carbide, aluminum oxide, silicon or amorphous carbon, the materials and the silicon oxide have good selective etching ratio, the material forming the sacrificial layer 9 comprises the silicon oxide, hydrogen fluoride gas can be released from the sacrificial layer 9, the hollowed-out structure shown in fig. 12 is formed, other film layers in the infrared detector are prevented from being influenced by the releasing process of the sacrificial layer 9, and the infrared detection performance of the infrared detector is optimized. In addition, the absorption plate structure 6 and the beam structure 8 comprise the thermosensitive layer 2 made of the same material, so that the manufacturing process of the infrared detector is simplified, and the manufacturing yield of the infrared detector is improved.

The embodiment of the disclosure sets the electrode layer to be positioned on one side of the heat-sensitive layer close to the substrate, does not need to manufacture an extra passivation layer, only the dielectric layer, the electrode layer and the heat-sensitive layer are arranged on the absorbing plate structure, the thickness of the absorbing plate structure is reduced, the heat capacity of the absorbing plate structure is further reduced, and the thermal response time of the infrared detector is reduced. In addition, the thermosensitive layer made of amorphous silicon, amorphous carbon, amorphous germanium or amorphous silicon germanium and other materials also covers the area where the beam structure is located, so that the thermal conductivity of the beam structure is favorably reduced, and the infrared response rate of the infrared detector is further improved.

It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The foregoing are merely exemplary embodiments of the present disclosure, which enable those skilled in the art to understand or practice the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.