CN204067379U - Novel zero volt response avalanche photodetector chip - Google Patents
Novel zero volt response avalanche photodetector chip Download PDFInfo
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- CN204067379U CN204067379U CN201420452401.6U CN201420452401U CN204067379U CN 204067379 U CN204067379 U CN 204067379U CN 201420452401 U CN201420452401 U CN 201420452401U CN 204067379 U CN204067379 U CN 204067379U
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Abstract
The utility model discloses a kind of novel zero volt response avalanche photodetector chip, comprise: substrate, resilient coating, absorbed layer, transition zone, field control layer, top layer, contact layer, N electrode, Zn diffusion region, passivating film, anti-reflection film and P electrode, described Zn diffusion region is carried out secondary diffusion by Zn diffusion technology and is formed, described Zn diffusion region comprises the multiplication region being positioned at middle part and the Zn diffuser ring being positioned at periphery, and the diffusion depth of described Zn diffuser ring is greater than the diffusion depth of described multiplication region.In the utility model, the multiplication region of Zn diffusion region and Zn diffuser ring are adopted the mode of Twi-lithography window and formed by twice conventional Zn diffusion technology, make simple and fast, can produce in batches; And obtained avalanche photodetector chip is without the need to requiring that bias voltage is greater than turning-on voltage, namely also has photoresponse electric current under zero V bias, is conducive to coupling efficiency; Also fundamentally inhibit P area edge punch-through effect, be conducive to reducing chip size.
Description
Technical field
The utility model relates to optical transport technology field, particularly relates to a kind of novel zero volt response avalanche photodetector chip (APD chip).
Background technology
Avalanche photo diode (APD) is widely used in the research of the aspects such as business, military affairs and scientific research.In recent years, along with the fast development of optical communication industry, the photodetector that play the most important role of receiver in optical communication system have also been obtained and develops rapidly.In optical communication system, the sensitivity of receiving device is one of important index, because always there is certain loss in light transmission in a fiber, so, at the receiving terminal of optical communication system, in order to capture the faint optical signal of optical transmission terminal, often adopt the avalanche photodetector chip that sensitivity is higher, i.e. APD chip.APD chip internal can collide ionization, and gain in being formed, 5-10dBm more excellent in the sensitivity of conventional photodiode (PIN), this makes APD chip become the first-selection of receiving device in optical communication system.
From traditional 2.5Gbit/s transmission rate 400Gbit/s transmission rate up till now, the requirement of high speed optical communication system to receiving device is more and more higher.Round to performance requirements such as receiving device high bandwidth, low noises, the design of researcher from developing material to device architecture has been carried out and has been studied widely.
In the research of APD chip device structure, traditional APD chip mainly contains meas structure and planarized structure, and wherein, meas structure has advantages such as making simply, can repeat, but not good at long term reliability; Compared with meas structure, because PN junction is buried in vivo by the APD chip of planarized structure, it has lower dark current and the stability of Geng Gao.But the APD chip of planarized structure also has several major issue needing to solve: 1, bias voltage need be greater than turning-on voltage and just can produce photoelectric current, is inconvenient to be coupled; 2, for preventing edge breakdown from adding guard ring, which has limited the size of chip size, and edge breakdown effect can not be eliminated completely.
In the fabrication processing of planarized structure APD chip, the P district formed due to diffusion or ion implantation has curvature effect, the electric field of APD chip edge is higher than the electric field of the PN junction of central authorities, therefore under the effect of high electric field, PN junction region does not also reach the degree of ionization by collision, and edge has punctured in advance.Tradition suppresses the method for edge breakdown to have multiple, and the first technology to utilize below P district growth part charge sheet to strengthen the electric field in PN district, and the electric field making the electric field in PN district be greater than edge first collides ionization.This technology first utilizes the method for metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy (MBE) at Grown absorbed layer and charge layer, then utilize again reactive ion etching (RIE) immediately below P district, etch a charge sheet, then continue the way growth dynode layer using metal organic chemical vapor deposition or molecular beam epitaxy.This technology relates to various technical processes, comprises diauxic growth, reactive ion etching etc., and technics comparing is complicated.The second technology is the material that the dynode layer of APD chip selects containing high aluminium component, absorbed layer selects the material not containing or contain low al composition, first allow in manufacturing process dynode layer lateral edge containing the materials from oxidizing formation alumina insulating layer of high aluminium component, making alumina insulating layer from being laterally expanded to P district, can effectively suppress P district electric field too high and the phenomenon punctured.But the length of alumina insulating layer needs high precision to control, and technical difficulty is high; Way the most conventional forms floating guard ring 200 in the devices, as shown in Figure 1.This way forms one or more ring-like window having certain intervals by photoetching technique is disposable on dynode layer, then by diffuseing to form heavily doped P district 300 and one or more guard ring 200.When APD chip operation, along with the rising of applied voltage, depleted region under P district 300 is toward side direction expansion until encounter the guard ring 200 of inner side, because guard ring 200 and the P district 300 at center are all heavy doping, between them, electromotive force is equal, depleted region just directly "jump" to the guard ring 200 in outside, expand depleted region, add the interval of edge, P district 300 equipotential line thus reduce the electric field at edge, P district 300, when voltage continues to raise, depleted region "jump" to again the guard ring 200 in outside from inner side guard ring 200, the electric field at further reduction edge, thus the effective electric field suppressing edge, P district 300, avoid punch-through.Adopt the APD chip that above several method makes; when bias voltage does not reach the turning-on voltage of APD chip to only not responding; the relation of its photoelectric current and bias voltage as shown in Figure 2; APD chip just must can produce photoelectric current when institute's biasing is greater than turning-on voltage; that is need to apply certain bias voltage to APD chip when being coupled just can be coupled; this makes troubles to coupling, and due to the existence of guard ring 200, limits the size of chip size.
Therefore, prior art existing defects, needs to improve.
Utility model content
The purpose of this utility model is to provide a kind of novel zero volt response avalanche photodetector chip, without the need to requiring that bias voltage is greater than turning-on voltage, namely under zero V bias, also having photoresponse electric current, being conducive to coupling efficiency; Also fundamentally inhibit P area edge punch-through effect, be conducive to reducing chip size.
The technical solution of the utility model is as follows: the utility model provides a kind of novel zero volt response avalanche photodetector chip, comprise: substrate, be formed at the resilient coating on described substrate, be formed at the absorbed layer on described resilient coating, be formed at the transition zone on described absorbed layer, be formed at the field control layer on described transition zone, be formed at the top layer on described field control layer, be formed at the contact layer on described top layer, be formed at the N electrode bottom described substrate, be formed at described contact layer, the Zn diffusion region in layer is controlled in top layer and field, be formed at the passivating film on described contact layer, be formed at the anti-reflection film on described Zn diffusion region, and be formed at described Zn diffusion region, P electrode on passivating film and anti-reflection film, described Zn diffusion region is carried out secondary diffusion by Zn diffusion technology and is formed, described Zn diffusion region comprises the multiplication region being positioned at middle part and the Zn diffuser ring being positioned at periphery, the diffusion depth of described Zn diffuser ring is greater than the diffusion depth of described multiplication region.
Described substrate is the semi-insulating InP substrate of N-shaped; Described resilient coating is that doping content is greater than 1X10
17cm
-3inP resilient coating, the thickness of described resilient coating is greater than 0.5 and is less than 2um; Described absorbed layer is that doping content is lower than 5X10
14cm
-3inGaAs absorbed layer, the thickness of described absorbed layer is greater than 1um and is less than 4um; Described transition zone is InGaAsP transition zone, and the cut-off wavelength of described transition zone is respectively 1.45um, 1.25um and 1.05um, and the thickness of described transition zone is greater than 0.01um and is less than 0.2um; Described field control layer is that doping content is greater than 1X10
17cm
-3inP field control layer, the thickness of described field control layer is greater than 0.1um and is less than 0.4um; Described top layer is that doping content is less than 1X10
15cm
-3inP top layer, the thickness of described top layer is greater than 3um and is less than 5um; Described contact layer is InGaAsP contact layer, and the thickness of described contact layer is greater than 0.1um and is less than 0.4um, and the cut-off wavelength of described contact layer is 1.05um.
Described anti-reflection film is formed by plasma enhanced chemical vapor deposition method deposited silicon nitride, and described passivating film is formed by plasma enhanced chemical vapor deposition method deposited silicon nitride or silicon dioxide.
The thickness of described P electrode is greater than 0.5um and is less than 2um, and described P electrode is formed by thermal evaporation or electron beam evaporation; The thickness of described N electrode is greater than 0.2um and is less than 1.5um, and described N electrode is formed by thermal evaporation or electron beam evaporation.
By in titanium, platinum, chromium and gold, one or more are formed described P electrode, and described N electrode is made up of gold.
Adopt such scheme, novel zero volt response avalanche photodetector chip of the present utility model, the multiplication region of its Zn diffusion region and Zn diffuser ring are adopted the mode of Twi-lithography window and formed by twice conventional Zn diffusion technology, make simple and fast, can produce in batches; And obtained avalanche photodetector chip is without the need to requiring that bias voltage is greater than turning-on voltage, namely also has photoresponse electric current under zero V bias, is conducive to coupling efficiency; Also fundamentally inhibit P area edge punch-through effect, be conducive to reducing chip size.
Accompanying drawing explanation
Fig. 1 is the structural representation of conventional avalanche photoelectric detector chip.
Fig. 2 is the graph of a relation of conventional avalanche photoelectric detector chip photoelectric current and bias voltage.
Fig. 3 is the schematic appearance of the utility model novel zero volt response avalanche photodetector chip.
Fig. 4 is the structure fabrication flow chart of the utility model novel zero volt response avalanche photodetector chip.
Fig. 5 is the entrance positions-photoelectric current schematic diagram of the utility model novel zero volt response avalanche photodetector chip.
Fig. 6 is the photoelectric current-bias relation schematic diagram of the utility model novel zero volt response avalanche photodetector chip.
Embodiment
Below in conjunction with the drawings and specific embodiments, the utility model is described in detail.
Refer to Fig. 3 to Fig. 6, the utility model provides a kind of novel zero volt response avalanche photodetector chip, comprise: substrate 2, be formed at the resilient coating 3 on described substrate 2, be formed at the absorbed layer 4 on described resilient coating 3, be formed at the transition zone 5 on described absorbed layer 4, be formed at the field control layer 6 on described transition zone 5, be formed at the top layer 7 on described field control layer 6, be formed at the contact layer 8 on described top layer 7, be formed at the N electrode 1 bottom described substrate 2, be formed at described contact layer 8, the Zn diffusion region 10 in layer 6 is controlled in top layer 7 and field, be formed at the passivating film 9 on described contact layer 8, be formed at the anti-reflection film 11 on described Zn diffusion region 10, and be formed at described Zn diffusion region 10, passivating film 9 and the P electrode 12 on anti-reflection film 11.Described Zn diffusion region 10 is carried out secondary diffusion by Zn diffusion technology and is formed, described Zn diffusion region 10 comprises the multiplication region 21 being positioned at middle part and the Zn diffuser ring 22 being positioned at periphery, described multiplication region 21 overlaps with Zn diffuser ring 22 formation one diffusion junctions, and the diffusion depth of described Zn diffuser ring 22 is greater than the diffusion depth of described multiplication region 21.The zero volt response avalanche photodetector chip of this structure also can produce photoelectric current under zero V bias, is conducive to coupling efficiency, as shown in Figure 6, but also fundamentally inhibits P area edge punch-through effect, also help reduction chip size, as shown in Figure 5.
Described resilient coating 3, absorbed layer 4, transition zone 5, field control layer 6, top layer 7 and contact layer 8 adopt Metalorganic chemical vapor deposition method (MOCVD) to be formed in successively on described substrate 2.Described substrate 2 is the semi-insulating InP substrate of N-shaped.Described resilient coating 3 is greater than 1X10 for doping content
17cm
-3inP resilient coating, the thickness of described resilient coating 3 is greater than 0.5 and is less than 2um, and in the present embodiment, the thickness of described resilient coating 3 is preferably greater than 1um and is less than 1.5um.Described absorbed layer 4 is that doping content is lower than 5X10
14cm
-3inGaAs absorbed layer, the thickness of described absorbed layer 4 is greater than 1um and is less than 4um, and in the present embodiment, the thickness of described absorbed layer 4 is preferably greater than 2um and is less than 3um.Described transition zone 5 is InGaAsP transition zone, the cut-off wavelength of described transition zone 5 is respectively 1.45um, 1.25um and 1.05um, the thickness of described transition zone 5 is greater than 0.01um and is less than 0.2um, and in the present embodiment, the thickness of described transition zone 5 is preferably greater than 0.05um and is less than 0.1um.Control layer 6 in described field is greater than 1X10 for doping content
17cm
-3inP field control layer, the thickness of described field control layer 6 is greater than 0.1um and is less than 0.4um, and in the present embodiment, the thickness of described field control layer 6 is preferably greater than 0.15um and is less than 0.25um; Described top layer 7 is less than 1X10 for doping content
15cm
-3inP top layer, the thickness of described top layer 7 is greater than 3um and is less than 5um, and in the present embodiment, the thickness of described top layer 7 is preferably greater than 3.5um and is less than 4.5um.Described contact layer 8 is InGaAsP contact layer, and the cut-off wavelength of described contact layer 8 is 1.05um, and the thickness of described contact layer 8 is greater than 0.1um and is less than 0.4um, and in the present embodiment, the thickness of described contact layer 8 is preferably greater than 0.2um and is less than 0.3um.
Described anti-reflection film 11 is formed by plasma enhanced chemical vapor deposition method (PECVD) deposited silicon nitride, and described anti-reflection film 11 place forms the photosensitive area of this chip.Described passivating film 9 is by plasma enhanced chemical vapor deposition method deposited silicon nitride (SiN
x) and silicon dioxide (SiO
2) and formed.
The thickness of described P electrode 12 is greater than 0.5um and is less than 2um, described P electrode 12 is formed by the method for thermal evaporation or electron beam evaporation and photoetching and wet etching, and described P electrode 12 is by titanium (Ti), platinum (Pt), chromium (Cr) or gold (Au), one or more are formed.The thickness of described N electrode 1 is greater than 0.2um and is less than 1.5um, and described N electrode 1 is formed by thermal evaporation or electron beam evaporation, and described N electrode 1 is made up of gold.
In sum, the utility model provides a kind of novel zero volt response avalanche photodetector chip, the multiplication region of its Zn diffusion region and Zn diffuser ring are adopted the mode of Twi-lithography window and formed by twice conventional Zn diffusion technology, make simple and fast, can produce in batches; And obtained avalanche photodetector chip is without the need to requiring that bias voltage is greater than turning-on voltage, namely also has photoresponse electric current under zero V bias, is conducive to coupling efficiency; Also fundamentally inhibit P area edge punch-through effect, be conducive to reducing chip size.
These are only preferred embodiment of the present utility model, be not limited to the utility model, all do within spirit of the present utility model and principle any amendment, equivalent to replace and improvement etc., all should be included within protection range of the present utility model.
Claims (5)
1. a novel zero volt response avalanche photodetector chip, it is characterized in that, comprise: substrate, be formed at the resilient coating on described substrate, be formed at the absorbed layer on described resilient coating, be formed at the transition zone on described absorbed layer, be formed at the field control layer on described transition zone, be formed at the top layer on described field control layer, be formed at the contact layer on described top layer, be formed at the N electrode bottom described substrate, be formed at described contact layer, the Zn diffusion region in layer is controlled in top layer and field, be formed at the passivating film on described contact layer, be formed at the anti-reflection film on described Zn diffusion region, and be formed at described Zn diffusion region, P electrode on passivating film and anti-reflection film, described Zn diffusion region is carried out secondary diffusion by Zn diffusion technology and is formed, described Zn diffusion region comprises the multiplication region being positioned at middle part and the Zn diffuser ring being positioned at periphery, the diffusion depth of described Zn diffuser ring is greater than the diffusion depth of described multiplication region.
2. novel zero volt response avalanche photodetector chip according to claim 1, it is characterized in that, described substrate is the semi-insulating InP substrate of N-shaped; Described resilient coating is that doping content is greater than 1X10
17cm
-3inP resilient coating, the thickness of described resilient coating is greater than 0.5 and is less than 2um; Described absorbed layer is that doping content is lower than 5X10
14cm
-3inGaAs absorbed layer, the thickness of described absorbed layer is greater than 1um and is less than 4um; Described transition zone is InGaAsP transition zone, and the cut-off wavelength of described transition zone is respectively 1.45um, 1.25um and 1.05um, and the thickness of described transition zone is greater than 0.01um and is less than 0.2um; Described field control layer is that doping content is greater than 1X10
17cm
-3inP field control layer, the thickness of described field control layer is greater than 0.1um and is less than 0.4um; Described top layer is that doping content is less than 1X10
15cm
-3inP top layer, the thickness of described top layer is greater than 3um and is less than 5um; Described contact layer is InGaAsP contact layer, and the thickness of described contact layer is greater than 0.1um and is less than 0.4um, and the cut-off wavelength of described contact layer is 1.05um.
3. novel zero volt response avalanche photodetector chip according to claim 1, it is characterized in that, described anti-reflection film is formed by plasma enhanced chemical vapor deposition method deposited silicon nitride, and described passivating film is formed by plasma enhanced chemical vapor deposition method deposited silicon nitride and silicon dioxide.
4. novel zero volt response avalanche photodetector chip according to claim 1, it is characterized in that, the thickness of described P electrode is greater than 0.5um and is less than 2um, and described P electrode is formed by thermal evaporation or electron beam evaporation; The thickness of described N electrode is greater than 0.2um and is less than 1.5um, and described N electrode is formed by thermal evaporation or electron beam evaporation.
5. novel zero volt response avalanche photodetector chip according to claim 4, it is characterized in that, by titanium, platinum, chromium and gold, one or more are formed described P electrode, and described N electrode is made up of gold.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104576786A (en) * | 2014-08-12 | 2015-04-29 | 深圳市芯思杰联邦国际科技发展有限公司 | Novel zero-volt-response avalanche photodetector chip and manufacturing method thereof |
| CN110611000A (en) * | 2018-08-02 | 2019-12-24 | 深圳市芯思杰联邦国际科技发展有限公司 | Back-in avalanche photodetector chip and manufacturing method thereof |
| CN110611011A (en) * | 2018-08-02 | 2019-12-24 | 深圳市芯思杰联邦国际科技发展有限公司 | Be ion diffusion protection ring avalanche photodetector chip and manufacturing method thereof |
| WO2020083082A1 (en) * | 2018-10-24 | 2020-04-30 | 芯思杰技术(深圳)股份有限公司 | Photoelectric detector, manufacturing method, and laser radar system |
-
2014
- 2014-08-12 CN CN201420452401.6U patent/CN204067379U/en not_active Withdrawn - After Issue
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104576786A (en) * | 2014-08-12 | 2015-04-29 | 深圳市芯思杰联邦国际科技发展有限公司 | Novel zero-volt-response avalanche photodetector chip and manufacturing method thereof |
| CN104576786B (en) * | 2014-08-12 | 2016-04-20 | 深圳市芯思杰联邦国际科技发展有限公司 | Novel zero volt response avalanche photodetector chip and preparation method thereof |
| CN110611000A (en) * | 2018-08-02 | 2019-12-24 | 深圳市芯思杰联邦国际科技发展有限公司 | Back-in avalanche photodetector chip and manufacturing method thereof |
| CN110611011A (en) * | 2018-08-02 | 2019-12-24 | 深圳市芯思杰联邦国际科技发展有限公司 | Be ion diffusion protection ring avalanche photodetector chip and manufacturing method thereof |
| WO2020083082A1 (en) * | 2018-10-24 | 2020-04-30 | 芯思杰技术(深圳)股份有限公司 | Photoelectric detector, manufacturing method, and laser radar system |
| JP2022505735A (en) * | 2018-10-24 | 2022-01-14 | フォグレイン テクノロジー （シェンゼン）カンパニー リミテッド | Photoelectric detector, manufacturing method and laser radar system |
| US11749772B2 (en) | 2018-10-24 | 2023-09-05 | Phograin Technology (shenzhen) Co., Ltd. | Photodetector, manufacturing method thereof, and lidar system |
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| GR01 | Patent grant | ||
| EE01 | Entry into force of recordation of patent licensing contract |
Assignee: SHENZHEN PHOGRAIN INTELLIGENT SENSING TECHNOLOGY CO., LTD. Assignor: SHENZHEN PHOGRAIN INTERNATIONAL TECHNOLOGY DEVELOPMENT CO., LTD. Contract record no.: 2015440020353 Denomination of utility model: Novel zero-volt-response avalanche photodetector chip and manufacturing method thereof Granted publication date: 20141231 License type: Common License Record date: 20151117 |
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Granted publication date: 20141231 Effective date of abandoning: 20160420 |
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| C25 | Abandonment of patent right or utility model to avoid double patenting |