CN220829969U - Visible light and near infrared sheet on-chip sensing structure - Google Patents
Visible light and near infrared sheet on-chip sensing structure Download PDFInfo
- Publication number
- CN220829969U CN220829969U CN202322392967.6U CN202322392967U CN220829969U CN 220829969 U CN220829969 U CN 220829969U CN 202322392967 U CN202322392967 U CN 202322392967U CN 220829969 U CN220829969 U CN 220829969U
- Authority
- CN
- China
- Prior art keywords
- type
- waveguide
- doped
- doping
- electron
- 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
- 238000010521 absorption reaction Methods 0.000 claims abstract description 34
- 239000000758 substrate Substances 0.000 claims abstract description 15
- 230000000694 effects Effects 0.000 claims description 21
- 230000004888 barrier function Effects 0.000 claims description 5
- 239000000725 suspension Substances 0.000 claims description 4
- 239000004038 photonic crystal Substances 0.000 claims description 3
- 239000000463 material Substances 0.000 abstract description 9
- 238000005530 etching Methods 0.000 abstract description 7
- 238000000034 method Methods 0.000 abstract description 6
- 230000003287 optical effect Effects 0.000 abstract description 6
- 230000035945 sensitivity Effects 0.000 abstract description 4
- 238000004891 communication Methods 0.000 abstract description 3
- 230000005540 biological transmission Effects 0.000 abstract 1
- 230000031700 light absorption Effects 0.000 abstract 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 9
- 229910052710 silicon Inorganic materials 0.000 description 9
- 239000010703 silicon Substances 0.000 description 9
- 230000004044 response Effects 0.000 description 8
- 238000002955 isolation Methods 0.000 description 7
- 239000004065 semiconductor Substances 0.000 description 6
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 230000007547 defect Effects 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 239000002210 silicon-based material Substances 0.000 description 3
- 229910052581 Si3N4 Inorganic materials 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000000151 deposition Methods 0.000 description 2
- 239000002019 doping agent Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 2
- 238000001039 wet etching Methods 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 239000006096 absorbing agent Substances 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 230000004807 localization Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 238000004321 preservation Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000002096 quantum dot Substances 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Abstract
The utility model discloses a visible light and near infrared on-chip sensing structure, in particular to a visible light and near infrared sensing structure with a suspended guided wave structure, which can realize optical waveguide transmission with high light limiting characteristics. By directly etching the substrate to form the absorption region, high efficiency light absorption is achieved by introducing a monocrystalline material. The method can be used for working scenes requiring the detector to have high sensitivity and low bias voltage, such as single photon flight time ranging, single photon quantum communication and calculation.
Description
Technical Field
The utility model belongs to the field of semiconductor devices, and particularly relates to a visible light and near infrared on-chip sensing structure which can be used for working scenes requiring a detector to have high sensitivity and low bias voltage, such as single photon flight time ranging, single photon quantum communication and calculation.
Background
With the development of single photon imaging and quantum communication systems, visible light and near infrared sensing devices are receiving a great deal of attention. How to realize a single photon detector with low noise, high response rate and low bias voltage is an important subject. The traditional photomultiplier tube needs operation voltage exceeding kilovolts, and has low quantum effect, large volume and poor performance stability. The surface-receiving silicon-based semiconductor avalanche diode requires an extremely thick silicon absorption layer to improve the quantum effect, resulting in excessively high bias voltage in the geiger mode, which is disadvantageous for high-speed response. The compound semiconductor-based surface-receiving avalanche diode has too high dark counts in geiger mode due to material defects, and requires increased sensitivity using low temperature environments, but exacerbates the post-pulse effect. The single photon detector based on superconducting materials and quantum dots works in an ultralow temperature environment and needs to bear the cost of a complex cooling and heat preservation system.
In contrast, the preparation process of the silicon material is mature and low in cost, and can effectively detect single photon with the wavelength of 400-1100 nm. And with the recent twenty years of silicon photonics, engineers have been able to implement various optical signal processing functions of silicon based on a 12 inch standard CMOS process. The silicon-based waveguide type avalanche diode detector has the characteristics of small volume, low power consumption, high quantum effect and high response speed, and the implementation of the silicon-based waveguide type avalanche diode detector by using a CMOS (complementary metal oxide semiconductor) process is an attractive choice.
However, for the visible and near infrared bands, silicon materials are inherently a good absorber material and therefore are not suitable for waveguide fabrication. If the waveguiding function is to be implemented in a CMOS process, other waveguiding materials, such as doped silicon oxide, doped silicon oxynitride, and silicon nitride materials, must be introduced. At this time, in order to reintroduce the silicon material, a deposition or epitaxial growth manner is often adopted, and such methods often introduce excessive crystal defects, which is not beneficial to the preparation of high-performance sensing devices.
Disclosure of utility model
The utility model aims to provide a visible light and near infrared on-chip sensing structure aiming at the defects of the prior art.
The utility model aims at realizing the following technical scheme: a sensing structure on visible light and near infrared sheet comprises an absorption region formed on a substrate, wherein the absorption region converts optical signals into electric signals, and the top of the absorption region is provided with a guided wave structure. In order to ensure the response rate and the response speed of the sensing device, the bottom of the absorption region and the substrate form a suspension structure through the suspension window, so that the effect is that the propagation of a light mode is further limited, the excessively low response degree caused by photons entering the substrate after passing through the absorption region is avoided, and the absorption region with a specific structure is formed, and the excessively thick absorption region is avoided, so that the response speed is reduced.
Further, a light isolation layer is formed at the top of the absorption region, the guided wave structure is embedded in the light isolation layer, and the light isolation layer can realize localization of light wave modes.
Further, the guided wave structure may be a ridge waveguide, a bar waveguide, a gap waveguide, or a photonic crystal waveguide.
Further, the substrate region corresponding to the bottom of the guided wave structure is doped through the barrier layer to realize etching stop.
Further, the doping structure of the absorption region is realized based on the photomultiplier effect or grating gate/photoconductive effect; specifically, the following three ways may be adopted but are not limited thereto:
1. The absorption region forms a doped structure based on the photomultiplier effect, specifically: the doped region doped with the first type of holes comprises a central axis of the guided wave structure and forms a diode structure with the region doped with the first type of electrons; the second type hole doping and the second type electron doping are positioned on two sides of the central axis of the guided wave structure and respectively comprise the third type hole doping and the third type electron doping so as to realize good contact with the electrode.
2. The absorption region forms an electron-hole-electron junction based on the grating gate/photoconductive effect, the central axis of the guided wave structure is contained in the doped region doped with the first type of hole, the doped regions doped with the second type of electron are respectively located at two sides of the central axis of the guided wave structure, and the doped region doped with the third type of electron is contained in the doped region doped with the second type of electron and is in good contact with the electrode.
3. The absorption region forms a hole-electron-hole junction based on the grating gate/photoconductive effect, the central axis of the guided wave structure is contained in the doped region doped with the first type of electrons, the doped regions doped with the second type of holes are respectively positioned at two sides of the central axis of the guided wave structure, and the doped region doped with the third type of holes is contained in the doped region doped with the second type of holes and is in good contact with the electrode later.
The utility model has the beneficial effects that: the absorption region of the sensing structure can be prepared from single crystal materials, and the photoelectric multiplication effect or the grating gate/photoconductive effect can be utilized to realize the on-chip sensing function with high sensitivity and high response rate.
Drawings
FIG. 1 is a schematic cross-sectional view of an on-chip sensing structure provided by the present disclosure;
fig. 2 (a), (b), and (c) are cross-sectional views of doped structures of the absorption region provided in the present disclosure;
FIG. 3 is a top view of an on-chip sensing structure prior to electrode formation provided by the present disclosure;
In the figure, 100 is a guided wave structure, 101 is a floating window, 102 is a light isolation layer, 103 is an electrode, 104 is an absorption region, 105 is a substrate, 201 is a first type hole doping, 202 is a second type hole doping, 203 is a third type hole doping, 204 is a first type electron doping, 205 is a second type electron doping, 206 is a third type electron doping, 207 is a blocking layer doping, and 300 is a floating window cantilever structure.
Detailed Description
In order that the above objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to the appended drawings.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways other than those described herein, and persons skilled in the art will readily appreciate that the present invention is not limited to the specific embodiments disclosed below.
For clarity, the following description of embodiments of the present utility model and related structures is primarily directed to single interconnect structures formed on semiconductor substrates. In practice, however, various embodiments may be implemented at the wafer level to form thousands of interconnect structures on hundreds of semiconductor die residing on a die, in view of efficiency.
In an embodiment of the present utility model, a schematic cross-sectional view of a visible and near infrared on-chip sensing structure is first described, as shown in fig. 1.
First, the absorption region 104 is formed in advance on the substrate 105, and the light isolation layer 102 is formed on top of the absorption region 104, and the light guide structure 100 is embedded in the light isolation layer 102.
Preferably, the substrate 105 material is silicon.
Preferably, the material of the waveguide structure 100 is silicon nitride.
Specifically, the waveguide structure 100 may be a common nano waveguide structure such as a ridge waveguide, a bar waveguide, a gap waveguide, a photonic crystal waveguide, and the like.
Next, the optical isolation layer 102 and the substrate 105 at the periphery of the waveguide structure 100 are etched to form a floating window 101, and an etching stop is achieved at the absorption region 104. The main doping structure of the absorption region 104 can be realized based on the photomultiplier effect or the grating gate/photoconductive effect, and the etch stop is realized by the barrier doping 207.
Specifically, as shown in fig. 2 (a) and (b), two possible doping configurations based on the grating gate/photoconductive effect implementation are shown, respectively.
In fig. 2 (a), an electron-hole-electron junction is formed, the axis of the waveguide structure 100 is included in the doped region of the first type hole dopant 201, and the doped regions of the second type electron dopant 205 are located on two sides of the axis of the waveguide structure 100, and remain symmetrical as much as possible. The doped region of the third type of electron doping 206 is included in the doped region of the second type of electron doping 205 and subsequently makes good contact with the electrode 103.
In fig. 2 (b), a hole-electron-hole junction is formed, the axis of the waveguide structure 100 is included in the doped region of the first type electron doping 204, and the doped regions of the second type hole doping 202 are located on two sides of the axis of the waveguide structure 100, and remain symmetrical as much as possible. The doped region of the third type hole doping 203 is included in the doped region of the second type hole doping 202 and subsequently forms a good contact with the electrode 103.
Specifically, as shown in fig. 2 (c), a doping structure realized based on the photomultiplier effect is shown. The first type hole doping 201 is used as a main absorption region, and the doped region includes a central axis of the waveguide structure 100 and forms a diode structure with a region where the first type electron doping 204 is located. The second type hole doping 202 and the second type electron doping 205 are located on two sides of the central axis of the waveguide structure 100, and respectively include the third type hole doping 203 and the third type electron doping 206 to achieve good contact with the electrode 103.
In particular, the absorption region 104 in this embodiment is formed by etching, and since in wet etching of silicon, the etching rate and the doping concentration (to be more than nineteenth power per cubic centimeter) are in inverse square relation, this property can be utilized to selectively perform high-energy heavy doping on the substrate region corresponding to the bottom of the guided wave structure 100 to form the barrier doping 207, and the planar structure of the absorption region 104 is further determined by the difference of the subsequent etching rates.
Fig. 3 shows the distribution of the absorption regions 104 in the case of a top view before the formation of the electrode 103 in this embodiment. The barrier doping 207 in the absorption region 104 causes the substrate 105 etch rate in that region to be drastically slowed and thus retained during wet etching. By optimizing the guided wave structure 100, the absorption region 104, and the suspended window suspended beam structure 300 designed for supporting the guided wave structure 100, a gradual transition from the optical signal in the guided wave structure 100 to the absorption region 104 is further realized, and reflection loss of the optical signal is reduced. Finally, the electrode 103 is formed on the absorption region 104 by etching and depositing a conductive material, and is responsible for transmitting the converted electrical signal.
The foregoing is merely a preferred embodiment of the present invention, and the present invention has been disclosed in the above description of the preferred embodiment, but is not limited thereto. Any person skilled in the art can make many possible variations and modifications to the technical solution of the present invention or modifications to equivalent embodiments using the methods and technical contents disclosed above, without departing from the scope of the technical solution of the present invention. Therefore, any simple modification, equivalent variation and modification of the above embodiments according to the technical substance of the present invention still fall within the scope of the technical solution of the present invention.
Claims (8)
1. The sensing structure on the visible light and near infrared sheet is characterized by comprising an absorption region formed on a substrate, wherein the top of the absorption region is provided with a guided wave structure, and the bottom of the absorption region and the substrate form a suspension structure through a suspension window.
2. The structure of claim 1, wherein the doping of the absorbing region is based on photomultiplier effect or grating/photoconductive effect.
3. The visible light and near infrared on-chip sensing structure of claim 1, wherein the substrate region corresponding to the bottom of the guided wave structure is etched by doping a barrier layer.
4. The structure of claim 1, wherein the light-absorbing region has a top light-isolating layer, and the waveguide is embedded in the light-isolating layer.
5. The structure of claim 1, wherein the waveguide structure is a ridge waveguide, a strip waveguide, a gap waveguide, or a photonic crystal waveguide.
6. The structure of claim 1, wherein the absorption region forms a doped structure based on photomultiplier effect, specifically: the doped region doped with the first type of holes comprises a central axis of the guided wave structure and forms a diode structure with the region doped with the first type of electrons; the second type hole doping and the second type electron doping are positioned on two sides of the central axis of the guided wave structure and respectively comprise the third type hole doping and the third type electron doping so as to realize good contact with the electrode.
7. The structure of claim 1, wherein the absorbing region forms an electron-hole-electron junction based on a grating gate/photoconductive effect, the central axis of the waveguide structure is included in a first type hole doped region, the second type electron doped regions are located on opposite sides of the central axis of the waveguide structure, and the third type electron doped regions are included in the second type electron doped regions and then form good contact with the electrode.
8. The structure of claim 1, wherein the absorption region forms a hole-electron-hole junction based on the grating gate/photoconductive effect, the central axis of the waveguide structure is included in the first type of electron-doped regions, the second type of hole-doped regions are located on opposite sides of the central axis of the waveguide structure, and the third type of hole-doped regions are included in the second type of hole-doped regions and then form good contact with the electrode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322392967.6U CN220829969U (en) | 2023-09-04 | 2023-09-04 | Visible light and near infrared sheet on-chip sensing structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322392967.6U CN220829969U (en) | 2023-09-04 | 2023-09-04 | Visible light and near infrared sheet on-chip sensing structure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220829969U true CN220829969U (en) | 2024-04-23 |
Family
ID=90726698
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202322392967.6U Active CN220829969U (en) | 2023-09-04 | 2023-09-04 | Visible light and near infrared sheet on-chip sensing structure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN220829969U (en) |
-
2023
- 2023-09-04 CN CN202322392967.6U patent/CN220829969U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9748429B1 (en) | Avalanche diode having reduced dark current and method for its manufacture | |
| CN113035982B (en) | All-silicon-doped multi-junction electric field enhanced germanium optical waveguide detector | |
| CN108010982B (en) | Waveguide composite coupling type single-row carrier detector | |
| CN103489953B (en) | The avalanche photodetector of a kind of two step evanescent field coupling | |
| JP2008526003A (en) | Germanium-on-silicon photodetector | |
| JP2005039269A (en) | Photodetector with enhanced responsibility | |
| CN109461787A (en) | The vertical coupled type of grating, which is inserted, refers to photodetector | |
| CN113097335B (en) | Waveguide coupling plasma enhanced Ge-based infrared photoelectric detector and preparation method thereof | |
| CN112993065A (en) | Avalanche photodetector based on Bragg grating and transverse waveguide structure | |
| CN108039389B (en) | Waveguide coupling type single-row carrier detector | |
| CN113838940A (en) | Integrated photoelectric detector and manufacturing method thereof | |
| CN220829969U (en) | Visible light and near infrared sheet on-chip sensing structure | |
| CN110808312B (en) | Preparation process method for improving output of photoelectric detector chip | |
| CN115295683A (en) | Single-carrier transport balance detector and preparation method thereof | |
| CN109119507B (en) | Graphene infrared detector preparation method based on integrated circuit process | |
| CN114497265B (en) | Avalanche photoelectric detector | |
| CN109494276A (en) | A kind of high-speed and high-efficiency visible light enhanced sensitivity silicon substrate avalanche photodiode array | |
| CN112420858B (en) | Silicon-based ridge waveguide photoelectric transistor detector | |
| CN220155555U (en) | On-chip integrated microwave photon detector | |
| Abdulwahid et al. | Physical modelling of InGaAs–InAlAs APD and PIN photodetectors for> 25 Gb/s data rate applications | |
| CN113629159B (en) | Silicon infrared enhanced evanescent wave coupling avalanche photodetector and manufacturing method thereof | |
| Yi et al. | High performance waveguide integrated vertical silicon-based germanium avalanche photodetectors | |
| CN218769537U (en) | Photon integrated gain detector structure | |
| CN114400267B (en) | Photoelectric detector integrated with double absorption areas and preparation method thereof | |
| CN117476800B (en) | Silicon-based photoelectric detector and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant |