CN117337053A - High-speed optical detector with high optical current gain and manufacturing method thereof - Google Patents
High-speed optical detector with high optical current gain and manufacturing method thereof Download PDFInfo
- Publication number
- CN117337053A CN117337053A CN202210712047.5A CN202210712047A CN117337053A CN 117337053 A CN117337053 A CN 117337053A CN 202210712047 A CN202210712047 A CN 202210712047A CN 117337053 A CN117337053 A CN 117337053A
- Authority
- CN
- China
- Prior art keywords
- electrode
- carbon nanotube
- nanotube array
- array film
- extrinsic
- 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.)
- Pending
Links
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 14
- 230000003287 optical effect Effects 0.000 title abstract description 21
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 91
- 239000002041 carbon nanotube Substances 0.000 claims abstract description 90
- 229910021393 carbon nanotube Inorganic materials 0.000 claims abstract description 90
- 239000000758 substrate Substances 0.000 claims abstract description 40
- 229910052751 metal Inorganic materials 0.000 claims description 75
- 239000002184 metal Substances 0.000 claims description 75
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims description 67
- 239000010408 film Substances 0.000 claims description 67
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 30
- 150000002739 metals Chemical class 0.000 claims description 24
- VBJZVLUMGGDVMO-UHFFFAOYSA-N hafnium atom Chemical compound [Hf] VBJZVLUMGGDVMO-UHFFFAOYSA-N 0.000 claims description 21
- 239000000956 alloy Substances 0.000 claims description 20
- 229910045601 alloy Inorganic materials 0.000 claims description 20
- 239000010931 gold Substances 0.000 claims description 20
- 229910052735 hafnium Inorganic materials 0.000 claims description 20
- 229910052763 palladium Inorganic materials 0.000 claims description 20
- 238000000034 method Methods 0.000 claims description 17
- 229910052706 scandium Inorganic materials 0.000 claims description 13
- SIXSYDAISGFNSX-UHFFFAOYSA-N scandium atom Chemical compound [Sc] SIXSYDAISGFNSX-UHFFFAOYSA-N 0.000 claims description 13
- 229910052691 Erbium Inorganic materials 0.000 claims description 10
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims description 10
- 229910017052 cobalt Inorganic materials 0.000 claims description 10
- 239000010941 cobalt Substances 0.000 claims description 10
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 10
- UYAHIZSMUZPPFV-UHFFFAOYSA-N erbium Chemical compound [Er] UYAHIZSMUZPPFV-UHFFFAOYSA-N 0.000 claims description 10
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 10
- 229910052737 gold Inorganic materials 0.000 claims description 10
- 229910052750 molybdenum Inorganic materials 0.000 claims description 10
- 239000011733 molybdenum Substances 0.000 claims description 10
- 229910052759 nickel Inorganic materials 0.000 claims description 10
- 229910052727 yttrium Inorganic materials 0.000 claims description 10
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 claims description 10
- 238000000151 deposition Methods 0.000 claims description 9
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims description 7
- 238000010894 electron beam technology Methods 0.000 claims description 5
- 239000005416 organic matter Substances 0.000 claims description 5
- 238000012546 transfer Methods 0.000 claims description 5
- 230000008021 deposition Effects 0.000 claims description 4
- 238000005566 electron beam evaporation Methods 0.000 claims description 4
- 239000011521 glass Substances 0.000 claims description 4
- 238000001755 magnetron sputter deposition Methods 0.000 claims description 4
- 239000010409 thin film Substances 0.000 claims description 4
- 239000010432 diamond Substances 0.000 claims description 3
- 229910003460 diamond Inorganic materials 0.000 claims description 3
- 239000011368 organic material Substances 0.000 claims description 3
- 238000000206 photolithography Methods 0.000 claims description 3
- 239000010453 quartz Substances 0.000 claims description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 3
- 230000004044 response Effects 0.000 abstract description 8
- 238000004891 communication Methods 0.000 abstract description 6
- 238000005516 engineering process Methods 0.000 abstract description 3
- 238000010923 batch production Methods 0.000 abstract 1
- 239000010410 layer Substances 0.000 description 25
- 230000008569 process Effects 0.000 description 10
- LUAZZOXZPVVGSO-UHFFFAOYSA-N Benzyl viologen Chemical compound C=1C=C(C=2C=C[N+](CC=3C=CC=CC=3)=CC=2)C=C[N+]=1CC1=CC=CC=C1 LUAZZOXZPVVGSO-UHFFFAOYSA-N 0.000 description 8
- 239000000463 material Substances 0.000 description 8
- 229920002873 Polyethylenimine Polymers 0.000 description 7
- 238000010586 diagram Methods 0.000 description 7
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 6
- 238000001259 photo etching Methods 0.000 description 6
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 5
- 229910052710 silicon Inorganic materials 0.000 description 5
- 239000010703 silicon Substances 0.000 description 5
- ROFVEXUMMXZLPA-UHFFFAOYSA-N Bipyridyl Chemical compound N1=CC=CC=C1C1=CC=CC=N1 ROFVEXUMMXZLPA-UHFFFAOYSA-N 0.000 description 4
- 239000011248 coating agent Substances 0.000 description 4
- 238000000576 coating method Methods 0.000 description 4
- 229920002120 photoresistant polymer Polymers 0.000 description 4
- 239000004065 semiconductor Substances 0.000 description 4
- 239000013077 target material Substances 0.000 description 4
- 238000005538 encapsulation Methods 0.000 description 3
- 238000005036 potential barrier Methods 0.000 description 3
- 238000004544 sputter deposition Methods 0.000 description 3
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 description 2
- 229910052581 Si3N4 Inorganic materials 0.000 description 2
- QARVLSVVCXYDNA-UHFFFAOYSA-N bromobenzene Chemical compound BrC1=CC=CC=C1 QARVLSVVCXYDNA-UHFFFAOYSA-N 0.000 description 2
- 239000002238 carbon nanotube film Substances 0.000 description 2
- 239000000969 carrier Substances 0.000 description 2
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 230000005684 electric field Effects 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 238000005286 illumination Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- -1 poly [9- (1-octyloxy) -9h carbazol-2, 7-diyl ] Polymers 0.000 description 2
- 229920003229 poly(methyl methacrylate) Polymers 0.000 description 2
- 239000004926 polymethyl methacrylate Substances 0.000 description 2
- 230000008054 signal transmission Effects 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
- 238000002207 thermal evaporation Methods 0.000 description 2
- UOCLXMDMGBRAIB-UHFFFAOYSA-N 1,1,1-trichloroethane Chemical compound CC(Cl)(Cl)Cl UOCLXMDMGBRAIB-UHFFFAOYSA-N 0.000 description 1
- SCYULBFZEHDVBN-UHFFFAOYSA-N 1,1-Dichloroethane Chemical compound CC(Cl)Cl SCYULBFZEHDVBN-UHFFFAOYSA-N 0.000 description 1
- OCJBOOLMMGQPQU-UHFFFAOYSA-N 1,4-dichlorobenzene Chemical compound ClC1=CC=C(Cl)C=C1 OCJBOOLMMGQPQU-UHFFFAOYSA-N 0.000 description 1
- LEVVHYCKPQWKOP-UHFFFAOYSA-N [Si].[Ge] Chemical compound [Si].[Ge] LEVVHYCKPQWKOP-UHFFFAOYSA-N 0.000 description 1
- 238000003491 array Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 229940117389 dichlorobenzene Drugs 0.000 description 1
- 239000003989 dielectric material Substances 0.000 description 1
- 238000000609 electron-beam lithography Methods 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 229910021389 graphene Inorganic materials 0.000 description 1
- 150000008282 halocarbons Chemical class 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000011147 inorganic material Substances 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000003475 lamination Methods 0.000 description 1
- 230000031700 light absorption Effects 0.000 description 1
- 239000002070 nanowire Substances 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical compound [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Abstract
The invention discloses a high-speed photodetector with high photocurrent gain and a manufacturing method thereof, comprising a substrate, a high-speed photodetector and a high-speed photodetector, wherein the substrate is provided with an extrinsic carbon nanotube array film; the first electrode is arranged on the extrinsic carbon nanotube array film and forms ohmic contact with the extrinsic carbon nanotube array film. A second electrode is provided on the extrinsic carbon nanotube array film opposite to the first electrode, and the second electrode forms a Schottky contact with the extrinsic carbon nanotube array film. The high-speed optical detector can obtain high optical current gain and high current response under reverse bias, meets the requirements of high responsivity and high response speed of the detector in optical communication, is compatible with the traditional CMOS technology, and is suitable for batch production.
Description
Technical Field
The present invention relates to a photoelectric device and a method for manufacturing the same, and more particularly, to a high-speed carbon nanotube photodetector and a method for manufacturing the same.
Background
With the development of optical communication and optical interconnection technologies, there is a need for a high-speed photodetector having a high bandwidth, high responsivity, low cost, small size, and high integration. The traditional III-V compound semiconductor material has incompatibility problem with a silicon-based CMOS process due to lattice mismatch, is difficult to integrate highly, and has complex process and high cost. The III-V nanowire photodetector can be directly prepared on a silicon substrate by epitaxial growth, but the device has low responsivity in the 1550nm optical communication band and complex process. The traditional germanium-silicon photodetector is compatible with a silicon-based CMOS process, has complex process and large dark current due to lattice mismatch. Graphene can achieve high-speed photodetection, has a broad response spectrum, but due to its ultra-thin and bandgap-free properties, the detector typically has low responsivity and large dark current.
Carbon nanotubes, which are representative of one-dimensional semiconductor materials, have unique and excellent electrical, optical and thermal properties, and are considered as representative of the construction of nanoscale integrated electronic devices. The carbon nano tube has no dangling bond on the surface, the gold-semiconductor contact potential barrier can be regulated by the contact metal work function, and the photodiode can be prepared by adopting high work function metals Pd, au and the like and low work function metals Hf, sc and the like, so that the process is simple and the cost is low. The carbon nanotube detector is compatible with silicon-based CMOS technology, and the detector can cover all communication wave bands. The high purity, high density carbon nanotube arrays can be prepared on a large scale, have high carrier mobility and saturation velocity, and have low intrinsic capacitance, exhibiting potential in rf transistors and high speed photodetection. However, the current single-layer carbon nanotube film has limited light absorption (less than 5%), low quantum efficiency and low light responsivity (about 10 mA/W), and cannot meet the requirements of high-speed optical interconnection and optical communication that the responsivity is more than 0.4A/W. Meanwhile, for the partial intrinsic (almost undoped) carbon nanotube film, high work function metals Pd, au and the like and low work function metals Hf, sc and the like are adopted to prepare an ohmic contact photodiode, so that a p-i-n-like junction is formed, but no obvious photocurrent gain exists, and the responsivity is still lower.
Based on the above, the invention provides a high-speed optical detector with high optical current gain and high optical responsivity and a manufacturing method thereof.
Disclosure of Invention
The embodiment of the invention provides a high-speed optical detector and a manufacturing method thereof, which can improve the response of photocurrent and the detection performance.
In a first aspect, embodiments of the present invention provide a high-speed photodetector with high photocurrent gain,
the device comprises a substrate, wherein the substrate is provided with an extrinsic carbon nanotube array film;
the first electrode is arranged on the extrinsic carbon nanotube array film and forms ohmic contact with the extrinsic carbon nanotube array film;
the extrinsic carbon nanotube array film has a second electrode opposite to the first electrode, and the second electrode forms a schottky contact with the extrinsic carbon nanotube array film.
Preferably, the substrate includes at least one of a high-resistance Si substrate, a quartz substrate, a diamond substrate, a glass substrate, or an SOI substrate.
Preferably, the extrinsic carbon nanotube array film is p-doped, and preferably, the p-doped is formed by wrapping p-type organic matter, and the p-type organic matter medium includes one of PCz (poly [9- (1-octyloxy) -9h carbazol-2, 7-diyl ]), PFO (poly (9, 9-dioxafluoronyl-2, 7-diyl)) or PFO-BPy (poly [ (9, 9-dioxafluoronyl-2, 7-diyl) -alt-co- (6, 6'- {2,2' -bipyridine });
preferably, the first electrode is a high work function metal, and the high work function metal includes one of palladium (Pd), gold (Au), molybdenum (Mo), nickel (Ni), and cobalt (Co), or an alloy or a stack composed of the metals;
preferably, the second electrode is a low work function metal comprising one of scandium (Sc), hafnium (Hf), yttrium (Y) or erbium (Er) or an alloy or stack of such metals.
Preferably, the extrinsic carbon nanotube array film is doped n-type, and the n-type doping is preferably formed by doping with an organic material including BV (benzyl viologen) molecules and PEI (polyethylene imine) molecules or an inorganic material including K atoms and Si atoms 3 N 4 、Al 2 O 3 Or HfO 2 One of them;
preferably, the first electrode is a low work function metal, and the low work function metal includes one of scandium (Sc), hafnium (Hf), yttrium (Y), or erbium (Er), or an alloy or stack of the metals;
preferably, the second electrode is a high work function metal, and the high work function metal includes one of palladium (Pd), gold (Au), molybdenum (Mo), nickel (Ni), and cobalt (Co), or an alloy or a stack composed of the metals.
Preferably, the first electrode and the second electrode are interdigital cascade electrodes.
Another aspect of the present invention provides a method for manufacturing a high-speed photodetector having a high photocurrent gain, including the steps of:
providing a substrate, and forming an extrinsic carbon nanotube array film on the substrate;
defining a first electrode pattern on the extrinsic carbon nanotube array film, and depositing a first metal layer on the first electrode pattern to form a first electrode, so that the first electrode and the extrinsic carbon nanotube array film form ohmic contact;
defining a second electrode pattern on the extrinsic carbon nanotube array film, and depositing a second electrode metal layer on the second cascade electrode pattern to form a second electrode opposite to the first electrode, so that the second electrode forms a schottky contact with the extrinsic carbon nanotube array film.
Preferably, the intrinsic carbon nanotube array film is formed by wet transfer or deposition lift-off, and then p-type or n-type doping is performed on the intrinsic carbon nanotube array film to form an extrinsic carbon nanotube array film.
Preferably, the extrinsic carbon nanotube array film is formed by p-doping the intrinsic carbon nanotube array film with a p-type organic encapsulation;
preferably, the p-type organic medium includes one of PCz (poly [9- (1-octyloxy) -9 Hcarbazol-2, 7-diyl ]), PFO (poly (9, 9-dialkylfluoronyl-2, 7-diyl)), or PFO-BPy (poly [ (9, 9-dialkylfluoronyl-2, 7-diyl) -alt-co- (6, 6'- {2,2' -bipyridine }) ];
preferably, the first metal layer is a high work function metal, and the high work function metal includes one of palladium (Pd), gold (Au), molybdenum (Mo), nickel (Ni), and cobalt (Co), or an alloy or a stack of the metals;
preferably, the second metal layer is a low work function metal, and the low work function metal includes one of scandium (Sc), hafnium (Hf), yttrium (Y), or erbium (Er), or an alloy or a stack of the metals.
Preferably, the extrinsic carbon nanotube array film is formed by n-doping the intrinsic carbon nanotube array film with an organic or inorganic medium;
preferably, the organic matter comprises BV (benzyl viologen) molecules and PEI (polyethylene imine) molecules, and the inorganic medium comprises K atoms and Si 3 N 4 、Al 2 O 3 Or HfO 2 One of them;
preferably, the first electrode is a low work function metal, and the low work function metal includes one of scandium (Sc), hafnium (Hf), yttrium (Y), or erbium (Er), or an alloy or stack of the metals;
preferably, the second electrode is a high work function metal, and the high work function metal includes one of palladium (Pd), gold (Au), molybdenum (Mo), nickel (Ni), and cobalt (Co), or an alloy or a stack composed of the metals.
Preferably, the first electrode pattern and the second electrode pattern are formed by photolithography or electron beam exposure;
preferably, the first electrode pattern and the second electrode pattern are interposed patterns;
preferably, the first electrode and the second electrode are formed by electron beam evaporation or magnetron sputtering.
The high-speed optical detector can realize high-speed optical detection, has higher bandwidth (more than 40 GHz) under reverse bias voltage, realizes high-speed optical signal transmission, can obtain high photocurrent gain (40) and high current responsivity (1.5A/W) under reverse bias voltage, and meets the requirements of optical communication on high responsivity and high response speed of the detector. Meanwhile, the high-speed photodetector manufacturing process is compatible with a silicon-based CMOS process, and is suitable for industrial mass production.
Drawings
The invention will be better understood from the following description of specific embodiments thereof taken in conjunction with the accompanying drawings, in which like or similar reference characters designate like or similar features.
FIG. 1 is a schematic diagram of a high-speed photodetector with a p-type carbon nanotube array film as the channel material;
FIG. 2 is a schematic diagram of a high-speed photodetector with an n-type carbon nanotube array film as the channel material;
FIG. 3 is a schematic diagram of a high-speed photodetector with a cascade finger structure according to the present invention, wherein the channel material is a p-type carbon nanotube array film;
FIG. 4 is a schematic diagram of the energy bands of a high speed photodetector of the present invention;
FIG. 5 is a graph of current versus voltage for a high speed photodetector of the invention in the dark state and under 1550nm illumination;
FIG. 6 is a graph showing the responsivity results of a high-speed photodetector of the present invention at various bias voltages;
FIG. 7 is a graph showing the frequency response of a high speed photodetector of the invention at two different bias voltages;
FIG. 8 is an eye diagram result of a high speed photodetector of the present invention;
Detailed Description
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In the drawings, like elements are denoted by like reference numerals, and various parts thereof are not drawn to scale. Furthermore, some well-known portions may not be shown. The semiconductor structure obtained after several steps may be depicted in one figure for simplicity.
It will be understood that when a layer, an area, or a structure of a device is described as being "on" or "over" another layer, another area, it can be referred to as being directly on the other layer, another area, or further layers or areas can be included between the other layer, another area, etc. And if the device is flipped, the one layer, one region, will be "under" or "beneath" the other layer, another region.
If, for the purposes of describing a situation directly on top of another layer, another region, the expression "a directly on top of B" or "a directly on top of B and adjoining it" will be used herein. In this application, "a is directly in B" means that a is in B and a is directly adjacent to B, rather than a being in the doped region formed in B.
This embodiment describes a high speed photodetector as shown with a substrate 101, the substrate 101 being a low parasitic capacitance substrate, in this embodiment a high resistance Si substrate is used, in other embodiments a quartz substrate, a diamond substrate, a glass substrate or an SOI substrate. The high-resistance Si substrate is provided with an extrinsic carbon nanotube array film 102 as a channel layer, and the extrinsic carbon nanotube array film 102 is obtained by p-type or n-type doping. In this embodiment, the extrinsic carbon nanotube array film is formed by wrapping carbon nanotubes with poly [9- (1-octylforming) -9Hcarbazole-2,7-diyl ] (PCz) molecules to form a p-type doped film, as shown in fig. 1, forming a p-type carbon nanotube array film 102 on a substrate 101. In other embodiments poly (9, 9-dioctyfluorenyl-2, 7-diyl)) (PFO) or poly [ (9, 9-dioctyfluorenyl-2, 7-diyl) -alt-co- (6, 6'- {2,2' -bipyridine }) (PFO-BPy) may also be used for p-type doping. The first electrode 103 forms ohmic contact with the p-type carbon nanotube array film by adopting a high work function metal, wherein the high work function metal comprises one of palladium (Pd), gold (Au), molybdenum (Mo), nickel (Ni) or cobalt (Co) or an alloy or a lamination layer composed of the metals; in one embodiment metallic palladium (Pd) is used as the first electrode, the thickness of which can be adjusted between 10nm and 120nm, preferably 60nm. The second electrode 104 is formed in schottky contact with the p-type carbon nanotube array film using a low work function metal including one of scandium (Sc), hafnium (Hf), yttrium (Y), or erbium (Er) or an alloy or stack of the above metals. Scandium (Sc) is used as the second electrode in this embodiment, and its thickness can be adjusted between 10nm and 120nm, preferably 80nm;
in another embodiment, as shown in FIG. 2, the extrinsic carbon nanotube array film 202 is formed by using organic BV (benzyl viologen) molecules, PEl (polyethylene imine) molecules or inorganic dielectrics K atoms, si 3 N 4 、Al 2 O 3 Or HfO 2 The n-type carbon nanotube array film is formed by isodoping, the first electrode 203 forms ohmic contact with the n-type carbon nanotube array film by adopting low work function metal, the low work function metal comprises scandium (Sc), hafnium (Hf), yttrium (Y) or erbium (Er) or an alloy or laminated layer formed by the metals, scandium (Sc) is adopted as the first electrode in the embodiment, and the thickness of the scandium (Sc) can be adjusted between 10nm and 120nm, and is preferably 80nm; the second electrode 204 is in schottky contact with the n-type carbon nanotube array film using a high work function metal including one of palladium (Pd), gold (Au), molybdenum (Mo), nickel (Ni), or cobalt (Co), or an alloy or stack of the above metals. In this embodiment metallic palladium (Pd) is used as the second electrode, the thickness of which can be adjusted between 10nm and 120nm, preferably 60nm.
In another embodiment, the first electrode and the second electrode are in a cascaded interdigital structure, as shown in fig. 3. And the channel length between the Pd cascade electrode and the Hf cascade electrode is smaller than 400nm, and the series resistance of the device is reduced by adopting a short-channel finger cascade structure, so that impedance matching is realized, and the photocurrent output is further improved.
In this embodiment, one end of the high-speed photodetector is in ohmic contact, and the other end is in schottky contact, and fig. 4 is a schematic diagram of an energy band of the high-speed photodetector, and the principle thereof is described below. For the channel material being a p-type doped carbon nanotube, the high work function Pd metal electrode can form p-type ohmic contact with the carbon nanotube, and the low work function Hf metal electrode can form n-type Schottky contact with the carbon nanotube. The electric field is formed mainly near the Hf electrode, and photogenerated carriers are generated mainly near the Hf electrode. When reverse bias is applied, the potential barrier near the Hf electrode is thinner, holes tunnel more easily, resulting in high photocurrent gain, while the detector has higher bandwidth due to high carrier mobility and saturation velocity.
For the light detector channel material is an n-type doped carbon nanotube, the Hf metal electrode with a low work function can form n-type ohmic contact with the carbon nanotube, and the Pd metal electrode with a high work function can form p-type Schottky contact with the carbon nanotube. The electric field is mainly formed near the Pd electrode, and photogenerated carriers are mainly generated near the Pd electrode. When bias is applied, the potential barrier near the Pd electrode is thinner, electrons tunnel more easily, resulting in high photocurrent gain.
FIG. 5 is a current-voltage curve for a high speed photodetector of one embodiment of the invention in the dark state and with 1550nm illumination, the detector having a dark current on the order of nA at zero bias; FIG. 6 is a graph showing the response of the high speed photodetector of one embodiment of the invention at different bias voltages, up to 1.5A/W for reverse bias; FIG. 7 is a graph showing the frequency response of a high-speed photodetector according to an embodiment of the invention at two different bias voltages, the device bandwidth at reverse bias voltage can reach above 40 GHz; FIG. 8 is an eye diagram of a high speed photodetector of one embodiment of the invention, showing that the detector can meet 40Gbit/s signal transmission.
Another embodiment of the present invention provides a method for manufacturing a high-speed photodetector, including the following steps: providing a high-resistance Si substrate, forming a high-density carbon nano tube array film on the high-resistance Si substrate by wet transfer or deposition lifting, specifically, transferring a high-density carbon nano tube array film layer to the high-resistance Si substrate by HF wet transfer, wherein PMMA is required to be used as a supporting layer in the process, and removing PMMA by acetone after transfer to form a high-density intrinsic carbon nano tube array film layer on the substrate. Secondly, the high-density carbon nanotube array film can be formed by a deposition lift-off method, firstly preparing a carbon nanotube solution, dissolving carbon nanotubes in one or more halogenated hydrocarbon, preferably chloroform, dichloroethane, trichloroethane, chlorobenzene, dichlorobenzene, bromobenzene and other organic solvents, then clamping the high-resistance Si substrate on a lift-off machine and immersing the high-resistance Si substrate in the carbon nanotube solution, and then forming a high-density carbon nanotube array film layer on the substrate by lifting the high-resistance Si substrate.
And forming an extrinsic carbon nanotube array thin film layer by performing p-type or n-type doping on the intrinsic carbon nanotube array thin film layer. In one embodiment, the p-doped carbon nanotube array film is formed by wrapping carbon nanotubes with poly [9- (1-octylonyl) -9 Hcarbazol-2, 7-diyl ] (PCz) molecules. In other embodiments, poly (9, 9-dioctyfluorenyl-2, 7-diyl)) (PFO) or poly [ (9, 9-dioctyfluorenyl-2, 7-diyl) -alt-co- (6, 6'- {2,2' -bipyridine }) (PFO-BPy) may also be used for p-type doping. And coating photoresist on the p-type doped carbon nanotube array film, forming a palladium (Pd) electrode pattern through photoetching or electron beam photoetching, placing a photoetched sample into an electronic or thermal evaporation system, evaporating a metal palladium (Pd) film with the thickness of 60nm after vacuumizing, and then placing the sample into acetone for stripping to remove a residual metal layer, thereby forming the palladium (Pd) electrode. The palladium (Pd) electrode forms an ohmic contact with the carbon nanotube array film.
Further, coating photoresist on the p-type doped carbon nanotube array film, forming a hafnium (Hf) electrode pattern by photolithography or electron beam lithography, placing the photoetched sample into a magnetron sputtering system, using metal hafnium (Hf) with purity of more than 98% as target material, and vacuumizing to 5×10 -6 About Torr, firstly, adopting a pre-sputtering process to further remove oxide on the surface of a hafnium (Hf) target material, and then using 1A/sA layer of 80nm thick hafnium metal (Hf) was sputter deposited to obtain an asymmetric diode structure. In another embodiment, electron beam evaporation may be used to obtain hafnium metal (Hf).
In another embodiment, the material is prepared by BV (benzyl viologen) molecules, PEI (polyethylene imine) molecules, or other organic substances or K atoms, si 3 N 4 、Al 2 O 3 Or HfO 2 And doping the inorganic medium to form an n-type doped carbon nano tube array film. Coating photoresist on the n-type doped carbon nanotube array film, forming a hafnium (Hf) first electrode pattern by photoetching or electron beam photoetching, placing the photoetched sample into a magnetron sputtering system, adopting metal hafnium (Hf) with purity of more than 98% as target material, and vacuumizing to 5×10 -6 About Torr, firstly, adopting a pre-sputtering process to further remove oxide on the surface of a hafnium (Hf) target material, and then sputtering and depositing a layer of 80nm thick metal hafnium (Hf) at a rate of 1A/s, thereby forming ohmic contact with the n-type doped carbon nano tube array film. In another embodiment, electron beam evaporation may be used to obtain hafnium metal (Hf).
And coating photoresist on the n-type doped carbon nanotube array film, forming a palladium (Pd) electrode pattern through photoetching or electron beam photoetching, placing a photoetched sample into an electronic or thermal evaporation system, evaporating a metal Pd film with the thickness of 60nm after vacuumizing, and then placing the sample into acetone for stripping to remove a residual metal layer, thereby forming the palladium (Pd) electrode. The palladium (Pd) electrode forms a Schottky contact with the carbon nanotube array film.
Further, the photodetector is coated with HfO with the thickness of 20nm 2 Or Al 2 O 3 An encapsulation medium Bao Fushang the carbon nanotube array film, a palladium (Pd) cascade electrode, and a hafnium (Hf) electrode. In other embodiments, the encapsulation medium may also be spin-on glass (SOG), silicon nitride (SiN) x ) Silicon oxide (SiO) 2 ) The thickness thereof may be in the range of 10nm to 2. Mu.m. The resulting high-speed photodetector of this embodiment.
While the invention has been described in detail in the general context and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that modifications and improvements can be made thereto. Accordingly, such modifications or improvements may be made without departing from the spirit of the invention and are intended to be within the scope of the invention as claimed.
Claims (10)
1. A high speed photodetector with high photocurrent gain, characterized by:
has a substrate with an extrinsic carbon nanotube array film thereon;
a first electrode is arranged on the extrinsic carbon nanotube array film, and ohmic contact is formed between the first electrode and the extrinsic carbon nanotube array film;
a second electrode is provided on the extrinsic carbon nanotube array film opposite to the first electrode, the second electrode forming a schottky contact with the extrinsic carbon nanotube array film.
2. The high-speed photodetector of claim 1, wherein said substrate comprises at least one of a high-resistance Si substrate, a quartz substrate, a diamond substrate, a glass substrate, or an SOI substrate.
3. The high-speed photodetector with high photocurrent gain according to claim 1, wherein said extrinsic carbon nanotube array film is p-doped;
preferably, the carbon nanotubes are encapsulated by a p-type organic material to form a p-type doping, wherein the p-type organic material comprises one of PCz, PFO or PFO-BPy;
preferably, the first electrode is a high work function metal, and the high work function metal includes one of palladium (Pd), gold (Au), molybdenum (Mo), nickel (Ni) or cobalt (Co), or an alloy or a stack composed of the above metals;
preferably, the second electrode is a low work function metal comprising one of scandium (Sc), hafnium (Hf), yttrium (Y) or erbium (Er) or an alloy or stack of the above metals.
4. The high-speed photodetector with high photocurrent gain according to claim 1, wherein said extrinsic carbon nanotube array film is n-doped;
preferably, the n-type doping is formed by doping with an organic matter including BV molecules and PEI molecules or an inorganic matter medium including K atoms and Si 3 N 4 、Al 2 O 3 Or HfO 2 One of them;
preferably, the first electrode is a low work function metal comprising one of scandium (Sc), hafnium (Hf), yttrium (Y) or erbium (Er) or an alloy or stack of the above metals;
preferably, the second electrode is a high work function metal including one of palladium (Pd), gold (Au), molybdenum (Mo), nickel (Ni), or cobalt (Co), or an alloy or stack composed of the above metals.
5. The high-speed photodetector with high photocurrent gain of claim 1, said first electrode and said second electrode being an interdigitated cascaded electrode.
6. A method of fabricating a high-speed photodetector having a high photocurrent gain as defined in any of claims 1 to 5, comprising the steps of:
providing a substrate, and forming an extrinsic carbon nanotube array film on the substrate;
defining a first electrode pattern on the extrinsic carbon nanotube array film, depositing a first metal layer on the first electrode pattern to form a first electrode, so that the first electrode and the extrinsic carbon nanotube array film form ohmic contact;
defining a second electrode pattern on the extrinsic carbon nanotube array film, depositing a second electrode metal layer on the second cascade electrode pattern to form a second electrode opposite to the first electrode, such that the second electrode forms a schottky contact with the extrinsic carbon nanotube array film.
7. The method of claim 6, wherein the intrinsic carbon nanotube array film is formed by wet transfer or deposition lift-off, and then the extrinsic carbon nanotube array film is formed by p-type or n-type doping of the intrinsic carbon nanotube array film.
8. The method of claim 7, wherein the extrinsic carbon nanotube array film is formed by p-type doping the intrinsic carbon nanotube array film with a p-type organic wrap;
preferably, the p-type organic medium comprises one of PCz, PFO or PFO-BPy;
preferably, the first metal layer is a high work function metal, and the high work function metal includes one of palladium (Pd), gold (Au), molybdenum (Mo), nickel (Ni) or cobalt (Co), or an alloy or a stack composed of the above metals;
preferably, the second metal layer is a low work function metal comprising one of scandium (Sc), hafnium (Hf), yttrium (Y) or erbium (Er) or an alloy or stack of the above metals.
9. The method of manufacturing a high-speed photodetector with high photocurrent gain according to claim 7, wherein said extrinsic carbon nanotube array thin film is formed by n-type doping said intrinsic carbon nanotube array thin film with an organic or inorganic medium;
preferably, the organic matter comprises BV molecules and PEI molecules, and the inorganic matter medium comprises K atoms and Si atoms 3 N 4 、Al 2 O 3 Or HfO 2 One of them;
preferably, the first electrode is a low work function metal comprising one of scandium (Sc), hafnium (Hf), yttrium (Y) or erbium (Er) or an alloy or stack of the above metals;
preferably, the second electrode is a high work function metal including one of palladium (Pd), gold (Au), molybdenum (Mo), nickel (Ni), or cobalt (Co), or an alloy or stack composed of the above metals.
10. The method of manufacturing a high-speed photodetector of claim 6, wherein said first electrode pattern and said second electrode pattern are formed by photolithography or electron beam exposure;
preferably, the first electrode pattern and the second electrode pattern are an inter-digitated pattern;
preferably, the first electrode and the second electrode are formed by electron beam evaporation or magnetron sputtering.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210712047.5A CN117337053A (en) | 2022-06-22 | 2022-06-22 | High-speed optical detector with high optical current gain and manufacturing method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210712047.5A CN117337053A (en) | 2022-06-22 | 2022-06-22 | High-speed optical detector with high optical current gain and manufacturing method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117337053A true CN117337053A (en) | 2024-01-02 |
Family
ID=89292052
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210712047.5A Pending CN117337053A (en) | 2022-06-22 | 2022-06-22 | High-speed optical detector with high optical current gain and manufacturing method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117337053A (en) |
-
2022
- 2022-06-22 CN CN202210712047.5A patent/CN117337053A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7173275B2 (en) | Thin-film transistors based on tunneling structures and applications | |
| US8778716B2 (en) | Integrated circuits based on aligned nanotubes | |
| US20160172527A1 (en) | Photodetector with Interdigitated Nanoelectrode Grating Antenna | |
| US9941382B2 (en) | Metal-semiconductor-metal (MSM) heterojunction diode | |
| US20050212079A1 (en) | Nanowire varactor diode and methods of making same | |
| JP6642769B1 (en) | Manufacturing method of electronic device using graphene | |
| US5780916A (en) | Asymmetric contacted metal-semiconductor-metal photodetectors | |
| JP6030416B2 (en) | Avalanche photodiode and manufacturing method thereof | |
| EP1743379A2 (en) | Hot electron transistor | |
| WO2011058544A2 (en) | Graphene-based photovoltaic device | |
| CN111640817A (en) | Suspended transverse double-heterojunction optical detector and manufacturing method thereof | |
| CN111628020A (en) | Photodiode based on TMDCs transverse PIN homojunction and preparation method | |
| CN111063731A (en) | CNT-IGZO thin film heterojunction bipolar transistor and preparation method and application thereof | |
| CN108767068B (en) | Two-dimensional material photodetector and manufacturing method thereof | |
| CN117337053A (en) | High-speed optical detector with high optical current gain and manufacturing method thereof | |
| CN111640768B (en) | Vertical double-heterojunction optical detector area array and manufacturing method thereof | |
| FR2604828A1 (en) | METHOD FOR MANUFACTURING A P + NN + DIODE AND A BIPOLAR TRANSISTOR HAVING THE SAME, USING THE NEUTRALIZATION EFFECT OF DONOR ATOMS BY ATOMIC HYDROGEN | |
| US20060260676A1 (en) | Photodetector | |
| US11164986B2 (en) | Avalanche photodiode and method of manufacturing the same | |
| KR102143778B1 (en) | Image sensor including mixed dimensional photo diode | |
| CN115440831A (en) | Photoelectric detector and manufacturing method thereof | |
| US20220238721A1 (en) | Semiconductor device including two-dimensional material | |
| CN113764584A (en) | N-type nano semiconductor device and preparation method thereof | |
| JP6563835B2 (en) | Light receiving element | |
| CN113948605A (en) | Photoelectric detector based on cadmium arsenide heterojunction and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication |