CN107340060B - Infrared sensor structure, preparation method and detection system - Google Patents
Infrared sensor structure, preparation method and detection system Download PDFInfo
- Publication number
- CN107340060B CN107340060B CN201710499752.0A CN201710499752A CN107340060B CN 107340060 B CN107340060 B CN 107340060B CN 201710499752 A CN201710499752 A CN 201710499752A CN 107340060 B CN107340060 B CN 107340060B
- Authority
- CN
- China
- Prior art keywords
- layer
- metal
- detection unit
- resonant cavity
- metal interconnection
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000001514 detection method Methods 0.000 title claims abstract description 177
- 238000002360 preparation method Methods 0.000 title abstract description 17
- 239000010410 layer Substances 0.000 claims description 219
- 229910052751 metal Inorganic materials 0.000 claims description 155
- 239000002184 metal Substances 0.000 claims description 155
- 239000011229 interlayer Substances 0.000 claims description 29
- 238000000034 method Methods 0.000 claims description 26
- 238000005530 etching Methods 0.000 claims description 7
- 238000011049 filling Methods 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 230000035945 sensitivity Effects 0.000 abstract description 4
- 239000003086 colorant Substances 0.000 description 17
- 239000011159 matrix material Substances 0.000 description 17
- 239000000463 material Substances 0.000 description 13
- 230000015572 biosynthetic process Effects 0.000 description 6
- 238000003786 synthesis reaction Methods 0.000 description 6
- 229910000577 Silicon-germanium Inorganic materials 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000005229 chemical vapour deposition Methods 0.000 description 3
- 238000005468 ion implantation Methods 0.000 description 2
- 238000002955 isolation Methods 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical group [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000000206 photolithography Methods 0.000 description 1
- 238000005240 physical vapour deposition Methods 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 238000000427 thin-film deposition Methods 0.000 description 1
- 238000005019 vapor deposition process Methods 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J2005/0077—Imaging
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Photometry And Measurement Of Optical Pulse Characteristics (AREA)
Abstract
The invention provides an infrared sensor structure, a preparation method and a detection system, wherein the infrared sensor structure is provided with a plurality of detection units; the plurality of detection units are provided with resonant cavities, and the heights of the resonant cavities of at least one part of the plurality of detection units are different from each other, so that the incident light frequencies absorbed by at least one part of the detection units are different from each other. The invention can effectively and specifically detect the infrared incident light of different wave bands by utilizing different wavelengths of light absorbed by the resonant cavities with different heights, and improves the detection sensitivity.
Description
Technical Field
The invention relates to the technical field of image sensors, in particular to an infrared sensor structure, a preparation method thereof and an infrared detection system.
Background
The output signal of the conventional infrared sensor is a gray signal, can only display the intensity and the weakness of an infrared absorption signal in a certain waveband, and can not display the intensity of a frequency signal of a certain waveband, and meanwhile, the output signal is a gray signal, so that the output signal is poor in intuition and is not easy to observe and judge intuitively by an actual user.
Disclosure of Invention
In order to overcome the above problems, the present invention aims to provide an infrared sensor structure and an infrared detection system, so that each band of infrared light can be subdivided and targeted detection can be performed, the detection sensitivity of infrared light of different bands can be improved, and the detection result can be visually observed.
In order to achieve the above object, the present invention provides an infrared sensor structure with multi-band output, which has a plurality of detecting units; the plurality of detection units are provided with resonant cavities, and the heights of the resonant cavities of at least one part of the plurality of detection units are different from each other, so that the incident light frequencies absorbed by at least one part of the detection units are different from each other.
Preferably, each detection unit has a sensitive material, the sensitive material is Si or Vox or SiGe, or Si or Vox or SiGe doped with B, Ge impurities is formed by ion implantation, and a metal reflecting layer is arranged at the bottom of the resonant cavity.
Preferably, the at least one part of the detection units are arranged in sequence according to the height of the resonant cavity, and the height of the resonant cavity is proportional to the wavelength of the absorbed incident light.
Preferably, at least a part of the detection units are arranged as a group of detection unit combinations, a plurality of groups of detection unit combinations in the infrared sensor structure are arranged in a matrix, and each group of detection unit combinations are sequentially arranged according to the height of the resonant cavity.
In order to achieve the above object, the present invention further provides an infrared detection system, which includes the above infrared sensor structure, a color assignor, and a pixel synthesizer; the color assignor assigns the incident light frequencies absorbed by the detection units in the infrared sensor structure to basic colors respectively, and the pixel synthesizer synthesizes the color values of the corresponding detection units according to the different basic colors formed by the detection units and the signal intensities detected by the detection units.
Preferably, at least a part of the detection units are arranged into a group of detection unit combinations, a plurality of groups of detection unit combinations in the infrared sensor structure are arranged in a matrix, and the detection unit combinations in each group are sequentially arranged according to the height of the resonant cavity;
the color assignor assigns different basic colors to the detection units in each group of detection unit combination, the basic colors corresponding to the detection units in each group of detection unit combination form a basic color combination, and each basic color combination corresponds to each group of detection unit combination one by one.
Preferably, in the basic color combinations, the different basic colors include red, green, blue and light blue, each group of detection unit combinations includes four detection units, the color assigner assigns red, green, blue and light blue to the four detection units respectively, and the four detection units are arranged in a 2 × 2 matrix.
Preferably, the pixel synthesizer sets the synthesis area of each detection unit to a 2 × 2 matrix including the detection unit, and synthesizes the color value of the detection unit by using four different basic colors in the 2 × 2 matrix.
Preferably, the scanning direction of the pixel synthesizer with respect to the detection units is set, and the synthesis region of each detection unit is a 2 × 2 matrix arranged with the detection unit in the scanning direction and a direction perpendicular to the scanning direction.
Preferably, the direction perpendicular to the scanning direction in each synthesis area is the same.
In order to achieve the above object, the present invention also provides a method for manufacturing an infrared sensor structure, which has a plurality of detecting units; the detection units are provided with resonant cavities, and the heights of the resonant cavities of at least one part of the detection units are different from each other, so that the incident light frequencies absorbed by at least one part of the detection units are different from each other; preparing the detection units in sequence from low to high according to the height of the resonant cavity; the resonant cavities are divided into N types corresponding to the N types of detection units; the method specifically comprises the following steps:
preparing a 1 st metal interconnection layer; 1 st metal is formed in the 1 st metal interconnection layer corresponding to the two sides of the region where the resonant cavity below the first type of detection unit is located;
forming a 2 nd interlayer dielectric layer and a 2 nd metal interconnection layer on the surface of the 1 st metal interconnection layer, wherein no metal is arranged in the resonant cavity region corresponding to the first type of detection unit, and the 2 nd metal is formed in the 2 nd metal interconnection layers on two sides of the resonant cavity corresponding to the first type of detection unit and two sides of the resonant cavity corresponding to the second type of detection unit;
forming a 3 rd interlayer dielectric layer and a 3 rd metal interconnection layer on the surfaces of the 2 layers of interlayer dielectric layers, wherein no metal is arranged in the region of the resonant cavity corresponding to the second type of detection unit, and a 3 rd metal is formed in the 3 rd metal interconnection layer on the two sides of the resonant cavity corresponding to the first type of detection unit, the two sides of the resonant cavity corresponding to the second type of detection unit and the two sides of the resonant cavity corresponding to the third type of detection unit;
……
repeating the steps until the Nth interlayer dielectric layer and the Nth metal interconnection layer are finished, and arranging no metal in the resonant cavity region corresponding to the N-1 type detection unit; the Nth metal interconnection layers on the two sides of the resonant cavity respectively corresponding to the first-class detection unit to the Nth-class detection unit are respectively provided with Nth metal; moreover, each layer of metal is electrically connected by adopting a contact hole;
forming a top layer dielectric layer on the Nth metal interconnection layer, forming a top layer contact hole in the top layer dielectric layer, wherein the top layer contact hole is contacted with the Nth metal of the Nth metal interconnection layer;
etching a corresponding area below the N types of detection units to be formed to obtain N types of grooves with different heights; the bottom of the groove etched below the Nth type detection unit is an Nth metal interconnection layer; n is not less than 2 and is an integer;
filling sacrificial layers in all the etched grooves;
forming a respective sensing structure on the sacrificial layer corresponding to each trench;
and removing all sacrificial layers through a release process, and forming corresponding resonant cavities below the sensing structure, thereby forming N types of detection units with resonant cavities with different heights.
Preferably, a metal reflecting layer is further formed at the bottom of the resonant cavity corresponding to the nth type detection unit in the nth metal interconnection layer.
According to the infrared sensor structure, the wavelength of light absorbed by the resonant cavities with different heights is different, infrared incident light with different wave bands can be effectively and specifically detected, the detection sensitivity is improved, basic colors are given to all detection units in the infrared sensor structure, and the final color values corresponding to the pixels are calculated according to the strength of detected signals and the basic colors, so that visual observation and judgment can be realized.
Drawings
FIG. 1 is a block diagram of an infrared detection system according to a preferred embodiment of the present invention
FIG. 2 is a schematic diagram of a matrix formed by the combination of detection units with basic colors according to a preferred embodiment of the present invention
FIG. 3 is a schematic diagram of an infrared sensor structure according to a preferred embodiment of the present invention
FIG. 4 is a flow chart illustrating a method for manufacturing an infrared sensor structure according to a preferred embodiment of the present invention
FIGS. 5-13 are schematic diagrams of various preparation steps of a preparation method of the infrared sensor structure of FIG. 4
Detailed Description
In order to make the contents of the present invention more comprehensible, the present invention is further described below with reference to the accompanying drawings. The invention is of course not limited to this particular embodiment, and general alternatives known to those skilled in the art are also covered by the scope of the invention.
The infrared sensor structure with multi-band output of the invention is provided with a plurality of detection units; the plurality of detection units are provided with resonant cavities, and the heights of the resonant cavities of at least one part of the plurality of detection units are different from each other, so that the incident light frequencies absorbed by at least one part of the detection units are different from each other. The resonant cavities with different heights are utilized to realize the targeted detection of each wave band of the infrared wave band, and the detection sensitivity is improved.
In addition, the infrared detection system comprises an infrared sensor structure, a color assignor and a pixel synthesizer; the incident light frequency absorbed by the detection units in the infrared sensor structure is respectively endowed with basic colors by the color assignor, and the color values of the corresponding detection units are synthesized by the pixel synthesizer according to different basic colors formed by the detection units and the signal intensity detected by the detection units, so that the color maps of signals in different frequency bands are finally obtained, and the signal intensity of each wave band can be observed and judged more intuitively.
According to the preparation method of the infrared sensor structure, the detection units are prepared in sequence from low to high according to the height of the resonant cavity; setting the height of the resonant cavity as N types corresponding to N types of detection units; the method specifically comprises the following steps:
preparing a 1 st metal interconnection layer; 1 st metal is formed in the 1 st metal interconnection layer corresponding to the two sides of the region where the resonant cavity below the first type of detection unit is located;
forming a 2 nd interlayer dielectric layer and a 2 nd metal interconnection layer on the surface of the 1 st metal interconnection layer, wherein no metal is arranged in the resonant cavity region corresponding to the first type of detection unit, and the 2 nd metal is formed in the 2 nd metal interconnection layers on two sides of the resonant cavity corresponding to the first type of detection unit and two sides of the resonant cavity corresponding to the second type of detection unit;
forming a 3 rd interlayer dielectric layer and a 3 rd metal interconnection layer on the surfaces of the 2 layers of interlayer dielectric layers, wherein no metal is arranged in the region of the resonant cavity corresponding to the second type of detection unit, and a 3 rd metal is formed in the 3 rd metal interconnection layer on the two sides of the resonant cavity corresponding to the first type of detection unit, the two sides of the resonant cavity corresponding to the second type of detection unit and the two sides of the resonant cavity corresponding to the third type of detection unit;
……
repeating the steps until the Nth interlayer dielectric layer and the Nth metal interconnection layer are finished, and arranging no metal in the resonant cavity region corresponding to the N-1 type detection unit; the Nth metal interconnection layers on the two sides of the resonant cavity respectively corresponding to the first-class detection unit to the Nth-class detection unit are respectively provided with Nth metal; moreover, each layer of metal is electrically connected by adopting a contact hole;
forming a top layer dielectric layer on the Nth metal interconnection layer, forming a top layer contact hole in the top layer dielectric layer, wherein the top layer contact hole is contacted with the Nth metal of the Nth metal interconnection layer;
etching a corresponding area below the N types of detection units to be formed to obtain N types of grooves with different heights; the bottom of the groove etched below the Nth type detection unit is an Nth metal interconnection layer; n is not less than 2 and is an integer;
filling sacrificial layers in all the etched grooves;
forming a respective sensing structure on the sacrificial layer corresponding to each trench;
and removing all sacrificial layers through a release process, and forming corresponding resonant cavities below the sensing structure, thereby forming N types of detection units with resonant cavities with different heights.
The present invention will be described in further detail with reference to the accompanying drawings 1 to 9 and specific embodiments. It should be noted that the drawings are in a simplified form and are not to precise scale, and are only used for conveniently and clearly achieving the purpose of assisting in describing the embodiment.
Referring to fig. 1, an infrared detection system of the present embodiment includes an infrared sensor structure, a color assignor, and a pixel synthesizer.
In this embodiment, the color assignor assigns the incident light frequencies absorbed by the plurality of detection units in the infrared sensor structure to the basic colors, respectively, and the pixel synthesizer synthesizes the color values of the corresponding detection units according to the different basic colors formed by the detection units and the signal intensities detected by the detection units.
Referring to fig. 2, at least a portion of the detecting units are arranged as a group of detecting unit combinations, as shown by a dashed line frame in fig. 2, the detecting unit combinations in the infrared sensor structure are arranged in a matrix, where the detecting units are combined into a 2 × 4 matrix, that is, a total of 8 detecting unit combinations, and the 8 detecting unit combinations have 32 detecting units; in each group of detection unit combinations, the detection units are arranged in sequence according to the height of the resonant cavity, for example, each column in each group of detection units is arranged from low to high or from high to low according to the height of the resonant cavity, and each row is arranged from low to high or from high to low according to the height of the resonant cavity; the color assignor assigns different basic colors to the detection units in each group of detection unit combination, the basic colors corresponding to the detection units in each group of detection unit combination form a basic color combination, and each basic color combination corresponds to each group of detection unit combination one by one. In this embodiment, as shown in fig. 2, in the basic color combination, different basic colors include red, green, blue, and light blue, each group of detection unit combination includes four detection units, the color assigner assigns red, green, blue, and light blue to the four detection units, respectively, and the four detection units are arranged according to a 2 × 2 matrix, as shown by the arrangement manner shown by the dashed line box in fig. 2.
Here, referring to fig. 2 again, the pixel synthesizer sets the synthesis area of each detection unit to be a 2 × 2 matrix including the detection unit, and synthesizes the color value of the detection unit by using four different basic colors in the 2 × 2 matrix. And the analogy is carried out in sequence to complete the color value synthesis of each detection unit in the whole infrared sensor structure.
The scanning direction of the pixel synthesizer with respect to the detection units is set, and the synthesis region of each detection unit is a 2 × 2 matrix arranged with the detection units in the scanning direction and the direction perpendicular to the scanning direction.
Referring to fig. 3, for convenience of description, four detecting units in a detecting unit combination are shown in a row in fig. 3, but this is not intended to limit the scope of the present invention; the infrared sensor structure with multi-band output of the embodiment is provided with four detection units; the four detecting units are all provided with resonant cavities Q1, Q2, Q3 and Q4, the four detecting units form a detecting unit combination, the detecting unit combination is provided with four detecting units with different heights of the resonant cavities Q1, Q2, Q3 and Q4, please refer to fig. 2, a plurality of groups of detecting unit combinations in the infrared sensor structure are arranged in a matrix, each group of detecting unit combinations are sequentially arranged according to the heights of the resonant cavities, and here, the heights of the resonant cavities are in direct proportion to the wavelength of absorbed incident light, namely, the higher the heights of the resonant cavities are, the higher the wavelength of the absorbed incident light is. In addition, as shown in fig. 3, the bottom of the resonant cavities Q1, Q2, Q3, Q4 of each detection unit is provided with a metal reflective layer M12, M22, M32, M42. Since there are four detecting units in the detecting unit combination, there are four metal interconnection layers 2011, 2021, 2031, 2041 and four dielectric layers (including three interlayer dielectric layers 2022, 2032, 2042 and one top dielectric layer 2052), and metal (square filled with oblique lines in each layer) is formed in the metal interconnection layer at two sides of the region where the resonant cavity Q1, Q2, Q3, Q4 under each detecting unit is located; furthermore, each metal layer is electrically connected to each other through a contact hole (a narrow rectangle between the squares filled with oblique lines), and referring to fig. 8 and fig. 9, the top dielectric layer 2052 has a top contact hole C4, which is in contact with the fourth metal M41 in the fourth metal interconnection layer 2041. Referring to fig. 3 again, a sensing structure is disposed above the resonant cavities Q1, Q2, Q3, and Q4, where the sensing structure is a microbridge structure 300, the microbridge structure 300 of the present embodiment may have a conductive layer 302 and a sensitive material layer 303, and in this embodiment, a lower release protection layer 301 is disposed at the bottom of the conductive layer 302, and the conductive layer 302 and the sensitive material layer 303 are covered by an upper release protection layer 304; the conductive layer 302 contacts the top of the top contact hole C4, or a contact block may be disposed on the top contact hole C4, so that the conductive layer 302 contacts the top contact block, and the contact block also supports the micro-bridge structure 300. Here, the material of the sensitive material layer 303 of each detection unit is Si or Vox or SiGe, or Si or Vox or SiGe doped with B, Ge or the like is formed by ion implantation.
Referring to fig. 4, for the method for manufacturing the infrared sensor structure of the present embodiment, the detecting units may be sequentially manufactured from low to high or from high to low according to the height of the resonant cavity; in the present embodiment, referring to fig. 3 again, in each detecting unit combination, the heights of the resonant cavities Q1, Q2, Q3, and Q4 are divided into 4 types, corresponding to 4 types of detecting units; since the infrared sensor structure of the present embodiment is formed by 8 detection unit combinations in a 2 × 4 matrix, the preparation method for each detection unit combination is the same, the detection units for the 8 detection unit combinations can be prepared at the same time, and the detection units for the same cavity height in the 8 detection unit combinations are also prepared at the same time. The method specifically comprises the following steps:
step 01: referring to fig. 5, a layer 1 metal interconnection layer 2011 is prepared; a 1 st metal M11 is formed in the 1 st metal interconnection layer 2011 corresponding to two sides of the resonant cavity of the first type detection unit;
specifically, the layer 1 metal interconnection layer 2011 may be formed on a silicon substrate 100, and a plurality of metal interconnection layers may be further disposed below the layer 1 metal interconnection layer 2011. The layer 1 metal interconnect layer 2011 may be prepared by first forming a metal M11 pattern, and then filling an isolation medium between the metal M11 patterns, or first forming an isolation medium layer, etching a groove, and then filling a metal M11 in the groove, thereby forming a layer 1 metal interconnect layer 2011. In this embodiment, a metal reflective layer M12 is further formed on the 1 st metal interconnect layer 2011 corresponding to the bottom of the resonant cavity of the first type of detection unit, and the metal reflective layer M12 may be made of Al. The metal reflective layer M12 can be compatible with the metal M11 in the process of fabricating the layer 1 metal interconnect 2011.
Step 02: referring to fig. 6, a 2 nd interlayer dielectric layer 2022, a contact hole C1 electrically connected to the 2 nd metal interconnection layer 2021, and a 2 nd metal interconnection layer 2021 are formed on the surface of the 1 st metal interconnection layer 2011, no metal is disposed in the 2 nd interlayer dielectric layer 2022 and the 2 nd metal interconnection layer 2021 corresponding to the resonant cavity region of the first type of detection unit, and a 2 nd metal M21 is formed in the 2 nd metal interconnection layer 2021 corresponding to both sides of the resonant cavity of the first type of detection unit and both sides of the resonant cavity of the second type of detection unit;
specifically, the layer 2 interlayer dielectric layer 2022 may be formed by, but not limited to, a chemical vapor deposition method, and the preparation of the layer 2 metal interconnection layer 2021 may refer to the preparation of the layer 1 metal interconnection layer 2011. In this embodiment, a metal reflective layer M22 is further formed on the bottom of the resonant cavity corresponding to the second type of detection unit in the layer 2 metal interconnection layer 2021, and the material of the metal reflective layer M22 may be Al. The metal reflective layer M22 can be prepared simultaneously with the metal M21 in the preparation process of the layer 2 metal interconnection layer 2021.
Step 03: referring to fig. 7, a 3 rd interlayer dielectric layer 2032, a contact hole C2 electrically connected to the 3 rd metal interconnection layer 2031 and a 3 rd metal interconnection layer 3032 are formed on the surface of the 2 nd metal interconnection layer 2021, no metal is disposed in the 3 rd interlayer dielectric layer 2032 and the 3 rd metal interconnection layer 2031 corresponding to the resonant cavity region of the second type detection unit and the resonant cavity region of the first type detection unit, and a 3 rd metal M31 is formed in the 3 rd metal interconnection layer 2031 corresponding to the two sides of the resonant cavity of the first type detection unit, the two sides of the resonant cavity of the second type detection unit and the two sides of the resonant cavity of the third type detection unit;
specifically, the interlayer dielectric layer 2032 of the 3 rd layer may be formed by, but is not limited to, a chemical vapor deposition method, and the preparation of the metal interconnection layer 2031 of the 3 rd layer may refer to the preparation of the metal interconnection layer 2011 of the 1 st layer. In this embodiment, a metal reflective layer M32 is further formed on the 3 rd metal interconnection layer 2031 at the bottom of the resonant cavity corresponding to the detection unit of the third type, and the material of the metal reflective layer M32 may be Al. The metal reflective layer M32 can be prepared simultaneously with the metal M31 in the process of preparing the layer 3 metal interconnection layer 2031.
Step 04: referring to fig. 8, a 4 th interlayer dielectric layer 2042, a contact hole C3 electrically connected to the 4 th interlayer metal layer 2041, and a 4 th interlayer metal layer 2041 are formed on the surface of the 3 rd interlayer metal layer 2031, no metal is disposed in the 4 th interlayer metal layer 2041 and the 4 th interlayer dielectric layer 2042 corresponding to the resonant cavity region of the third type of detection unit, and a 4 th metal M41 is formed in the 4 th interlayer metal layer 2041 corresponding to the two sides of the resonant cavity of the first type of detection unit, the two sides of the resonant cavity of the second type of detection unit, the two sides of the resonant cavity of the third type of detection unit, and the two sides of the resonant cavity region of the fourth type of detection unit;
specifically, the 4 th interlayer dielectric layer 2042 may be formed by, but not limited to, a chemical vapor deposition method, and the preparation of the 4 th metal interconnection layer 2041 may refer to the preparation of the 1 st metal interconnection layer 2011. In this embodiment, a metal reflective layer M42 is further formed on the 4 th metal interconnection layer 2041 at the bottom of the resonant cavity corresponding to the fourth type of detection unit, and the material of the metal reflective layer M42 may be Al. The metal reflective layer M42 can be compatible with the metal M41 in the process of fabricating the layer 4 metal interconnection layer 2042.
It should be noted that, when the preparation of each interlayer dielectric layer and each metal interconnection layer can be obtained by the above method, the nth interlayer dielectric layer and the nth metal interconnection layer are obtained by preparation.
In the embodiment, each layer of metal is electrically connected by adopting a contact hole; the metal filled in the contact hole is tungsten. The metals M11, M21, M31 and M41 in the above-mentioned layer 1 to layer 4 metal interconnection layers may be Al.
Step 05: referring to fig. 9, a top dielectric layer 2052 is formed on the 4 th metal interconnection layer 2041, a top contact hole C4 is formed in the top dielectric layer 2052, and the top contact hole C4 is in contact with the 4 th metal of the 4 th metal interconnection layer 2041;
specifically, the top dielectric layer 2052 may be formed by, but not limited to, a vapor deposition process, and then the top contact hole C4 is etched in the top dielectric layer 2052 by a photolithography and etching process, and the top contact hole C4 is filled with a conductive metal, which may be tungsten.
Step 06: referring to fig. 10, etching regions corresponding to resonant cavities of 4 types of detection units to be formed (total 32 detection units) to obtain 4 types of trenches (total 32 trenches) with different heights;
specifically, the trench etched in each type of detection unit corresponds to the target size of the resonant cavity of the corresponding type of detection unit, in this embodiment, the bottom of the trench etched in the type 1 detection unit is the metal reflective layer M12 in the layer 1 metal interconnection layer 2011; the bottom of the etched groove in the type 2 detection unit is a metal reflecting layer M22 in the layer 2 metal interconnection layer 2021; the bottom of the trench etched in the type 3 detection unit is the metal reflective layer M32 in the layer 3 metal interconnection layer 2031; the bottom of the trench etched in the type 4 detection unit is the metal reflective layer M42 in the layer 4 metal interconnection layer 2041.
Step 07: referring to fig. 11, filling all the etched trenches with a sacrificial layer;
specifically, a physical vapor deposition method may be used to deposit the sacrificial layer, and the sacrificial layer may be an inorganic sacrificial material or an organic sacrificial material, such as amorphous silicon.
Step 08: referring to fig. 12, a corresponding sensing structure is formed on the sacrificial layer corresponding to each trench;
specifically, the sensing structure of the present embodiment is the micro-bridge structure 300, and the micro-bridge structure 300 including the conductive layer 302, the sensitive material layer 303, the upper release protection layer 304, and the lower release protection layer 301 may be formed by a combination of thin film deposition and etching processes, which may be known by those skilled in the art and will not be described herein again. Here, the conductive layer 302 of the micro-bridge structure 300 needs to be in contact with the top of the top contact hole C4, so as to realize signal transmission of the micro-bridge structure 300 to the outside.
It should be noted here that the sensing structure may or may not have a release hole, and if the conductive layer 302 of the sensing structure is in contact with the top contact hole C4 as shown in this embodiment, a release hole K1 is provided; if, as in the other embodiments, the conductive layer of the microbridge structure is in contact with the top contact via a contact bump, no release via is required due to the gap between the microbridge structure and the sacrificial layer.
Step 09: referring to fig. 13, after the release process, all the sacrificial layers are removed, and corresponding resonant cavities Q1, Q2, Q3, and Q4 are formed below the sensing structure, thereby forming 4 types of detecting units with different heights of resonant cavities Q1, Q2, Q3, and Q4.
Specifically, the release process may employ a conventional release process. For different sacrificial layer materials, a release process, such as a wet etch process, may be employed. In this embodiment, the detecting units having 4 types of resonant cavities Q1, Q2, Q3 and Q4 with different heights are formed, and the detecting units having 4 types of resonant cavities Q1, Q2, Q3 and Q4 with different heights are arranged in a 2 × 2 matrix and height sequence, for example, highest, next highest, medium and low sequence are arranged in a 2 × 2 matrix around the detecting units, as shown in fig. 2.
Although the present invention has been described with reference to preferred embodiments, it is to be understood that the present invention is not limited to the disclosed embodiments, but rather, may be embodied in many different forms and modifications without departing from the spirit and scope of the present invention as defined by the appended claims.
Claims (2)
1. A method of making an infrared sensor structure having a plurality of detection units; the detection units are provided with resonant cavities, and the heights of the resonant cavities of at least one part of the detection units are different from each other, so that the incident light frequencies absorbed by at least one part of the detection units are different from each other; the method is characterized in that the detection units are sequentially prepared from low to high according to the height of the resonant cavity; the resonant cavities are divided into N types corresponding to the N types of detection units; the method specifically comprises the following steps:
preparing a 1 st metal interconnection layer; 1 st metal is formed in the 1 st metal interconnection layer corresponding to the two sides of the region where the resonant cavity below the first type of detection unit is located;
forming a 2 nd interlayer dielectric layer and a 2 nd metal interconnection layer on the surface of the 1 st metal interconnection layer, wherein no metal is arranged in the resonant cavity region corresponding to the first type of detection unit, and the 2 nd metal is formed in the 2 nd metal interconnection layers on two sides of the resonant cavity corresponding to the first type of detection unit and two sides of the resonant cavity corresponding to the second type of detection unit;
forming a 3 rd interlayer dielectric layer and a 3 rd metal interconnection layer on the surfaces of the 2 layers of interlayer dielectric layers, wherein no metal is arranged in the region of the resonant cavity corresponding to the second type of detection unit, and a 3 rd metal is formed in the 3 rd metal interconnection layer on the two sides of the resonant cavity corresponding to the first type of detection unit, the two sides of the resonant cavity corresponding to the second type of detection unit and the two sides of the resonant cavity corresponding to the third type of detection unit;
……
repeating the steps until the Nth interlayer dielectric layer and the Nth metal interconnection layer are finished, and arranging no metal in the resonant cavity region corresponding to the N-1 type detection unit; the Nth metal interconnection layers on the two sides of the resonant cavity respectively corresponding to the first-class detection unit to the Nth-class detection unit are respectively provided with Nth metal; moreover, each layer of metal is electrically connected by adopting a contact hole;
forming a top layer dielectric layer on the Nth metal interconnection layer, forming a top layer contact hole in the top layer dielectric layer, wherein the top layer contact hole is contacted with the Nth metal of the Nth metal interconnection layer;
etching a corresponding area below the N types of detection units to be formed to obtain N types of grooves with different heights; the bottom of the groove etched below the Nth type detection unit is an Nth metal interconnection layer; n is not less than 2 and is an integer;
filling sacrificial layers in all the etched grooves;
forming a respective sensing structure on the sacrificial layer corresponding to each trench;
and removing all sacrificial layers through a release process, and forming corresponding resonant cavities below the sensing structure, thereby forming N types of detection units with resonant cavities with different heights.
2. The manufacturing method according to claim 1, wherein a metal reflective layer is further formed on the bottom of the resonant cavity corresponding to the nth type detection unit in the nth metal interconnection layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710499752.0A CN107340060B (en) | 2017-06-27 | 2017-06-27 | Infrared sensor structure, preparation method and detection system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710499752.0A CN107340060B (en) | 2017-06-27 | 2017-06-27 | Infrared sensor structure, preparation method and detection system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107340060A CN107340060A (en) | 2017-11-10 |
| CN107340060B true CN107340060B (en) | 2020-01-10 |
Family
ID=60221627
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710499752.0A Active CN107340060B (en) | 2017-06-27 | 2017-06-27 | Infrared sensor structure, preparation method and detection system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107340060B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113720464B (en) * | 2021-03-26 | 2022-09-06 | 北京北方高业科技有限公司 | Infrared detector mirror image element based on CMOS (complementary metal oxide semiconductor) process and infrared detector |
| CN113432724B (en) * | 2021-06-25 | 2023-03-24 | 北京北方高业科技有限公司 | Uncooled tuned infrared detector |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5159199A (en) * | 1991-08-12 | 1992-10-27 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Integrated filter and detector array for spectral imaging |
| CN2121022U (en) * | 1992-01-07 | 1992-11-04 | 北京市计量科学研究所 | Color temp. meter |
| US5656816A (en) * | 1995-01-20 | 1997-08-12 | Nec Corporation | Infrared detector and drive method therefor |
| US6392232B1 (en) * | 1995-07-21 | 2002-05-21 | Pharmarcopeia, Inc. | High fill factor bolometer array |
| CN1379856A (en) * | 1999-07-23 | 2002-11-13 | 应用色彩系统公司 | Colorimeter |
| US6495829B1 (en) * | 1999-01-12 | 2002-12-17 | Nec Corporation | Thermal infrared array sensor for detecting a plurality of infrared wavelength bands |
| CN104568756A (en) * | 2015-01-21 | 2015-04-29 | 中国科学院上海技术物理研究所 | Medium-wave infrared spectrum identifiable detector |
| CN106404708A (en) * | 2016-10-28 | 2017-02-15 | 成都市亿泰科技有限公司 | Drug abuse microsensor based on infrared spectroscopy |
-
2017
- 2017-06-27 CN CN201710499752.0A patent/CN107340060B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5159199A (en) * | 1991-08-12 | 1992-10-27 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Integrated filter and detector array for spectral imaging |
| CN2121022U (en) * | 1992-01-07 | 1992-11-04 | 北京市计量科学研究所 | Color temp. meter |
| US5656816A (en) * | 1995-01-20 | 1997-08-12 | Nec Corporation | Infrared detector and drive method therefor |
| US6392232B1 (en) * | 1995-07-21 | 2002-05-21 | Pharmarcopeia, Inc. | High fill factor bolometer array |
| US6495829B1 (en) * | 1999-01-12 | 2002-12-17 | Nec Corporation | Thermal infrared array sensor for detecting a plurality of infrared wavelength bands |
| CN1379856A (en) * | 1999-07-23 | 2002-11-13 | 应用色彩系统公司 | Colorimeter |
| CN104568756A (en) * | 2015-01-21 | 2015-04-29 | 中国科学院上海技术物理研究所 | Medium-wave infrared spectrum identifiable detector |
| CN106404708A (en) * | 2016-10-28 | 2017-02-15 | 成都市亿泰科技有限公司 | Drug abuse microsensor based on infrared spectroscopy |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107340060A (en) | 2017-11-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10903259B2 (en) | Image sensor | |
| KR102278324B1 (en) | Semiconductor image sensor | |
| US7924504B2 (en) | Color filter structure having inorganic layers | |
| US20090189055A1 (en) | Image sensor and fabrication method thereof | |
| CN107340060B (en) | Infrared sensor structure, preparation method and detection system | |
| WO2008085385A2 (en) | Plasmonic fabry-perot filter | |
| US20080159658A1 (en) | Image Sensor and Method for Manufacturing The Same | |
| CN107039468A (en) | CIS and preparation method thereof | |
| CN109791073B (en) | Multispectral imaging device | |
| CN103972252B (en) | Color filter including clear pixel and hard mask | |
| US20160218131A1 (en) | Photo diode and method of forming the same | |
| CN105518875A (en) | Photoelectric conversion device and method for manufacturing same | |
| KR20190056902A (en) | An image sensor | |
| CN105278010B (en) | Method for manufacturing silicon dioxide microlens | |
| CN210296379U (en) | Multispectral image sensor and multispectral sensor | |
| CN102751299B (en) | Low-cost high-integration BSI image sensor packaging | |
| CN114843292A (en) | Spectrum chip, preparation method thereof and spectrum analysis device | |
| US8415813B2 (en) | Identification of dies on a semiconductor wafer | |
| KR20170073910A (en) | Light field imaging device and method for fabricating the same | |
| EP1425800A2 (en) | Image sensor with recessed planarizing layers and method for making same | |
| US20210288087A1 (en) | Multispectral imaging sensor provided with means for limiting crosstalk | |
| CN105206636A (en) | Adjustable hybrid imaging detector pixel structure and preparation method thereof | |
| EP3024029B1 (en) | Method of producing a semiconductor device comprising an aperture array | |
| CN107367330B (en) | Infrared sensor structure and preparation method thereof, detection system | |
| US10700221B2 (en) | Microlens having a carrier-free optical interference filter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |