CN202405298U - Near-infrared band full-silicon-based nano photoelectric detector - Google Patents
Near-infrared band full-silicon-based nano photoelectric detector Download PDFInfo
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- CN202405298U CN202405298U CN2011205748241U CN201120574824U CN202405298U CN 202405298 U CN202405298 U CN 202405298U CN 2011205748241 U CN2011205748241 U CN 2011205748241U CN 201120574824 U CN201120574824 U CN 201120574824U CN 202405298 U CN202405298 U CN 202405298U
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Abstract
The utility model discloses a near-infrared band full-silicon-based nano photoelectric detector. The near-infrared band full-silicon-based nano photoelectric detector comprises a substrate, a silicon nanowire optical waveguide, a schottky contact electrode, an ohm contact electrode and an insulating layer. The silicon nanowire optical waveguide is constructed on the substrate; the schottky contact electrode is covered at the top and on the side wall of the silicon nanowire optical waveguide; the insulating layer is coated between the silicon nanowire optical waveguide and the schottky contact electrode; and the ohm contact electrode is arranged at the position in a panel region of the silicon nanowire optical waveguide, which is at a distance of 1 to 2mum with the schottky contact electrode. Incident light is input from the silicon nanowire optical waveguide, is adsorbed in a schottky contact region and is converted into photon-generated carriers by an internal optical emission effect and the photon-generated carriers are collected by the schottky contact electrode and the ohm contact electrode to form a photocurrent so as to implement photoelectric conversion. According to the utility model, the physical limit that near-infrared light cannot be adsorbed by large energy gap silicon is overcome; the near-infrared band full-silicon-based nano photoelectric detector has the excellent characteristics of super large bandwidth, polarization insensitivity and the like; and due to high adsorption rate, the near-infrared band full-silicon-based nano photoelectric detector can be made very small, the process preparation is compatible to a CMOS (Complementary Metal Oxide Semiconductor) and the near-infrared band full-silicon-based nano photoelectric detector is simple to manufacture and has low cost.
Description
Technical field
The utility model relates to technical field of photoelectric detection, relates in particular to a kind of near infrared band total silicon base nano photoelectric detector.
Background technology
Get into 21 century; The electrical interconnection technical development is to nanoscale; Met with the big and signal delay two big physics bottlenecks of power consumption, and the light interconnection technique is big because of capacity, bandwidth is big, extensive concern is elected and obtained to advantage such as low in energy consumption, especially silicon chip glazing interconnection technique is more had an optimistic view of by consistent; Because silicon has ripe micro-nano processed technology, and good optical, electrology characteristic are arranged.Yet opto electronic device dimensional mismatch, wide bandgap semiconductor silicon materials do not have absorption at the optical communicating waveband that is lower than its band-gap energy (1.12eV) (wavelength is greater than 1.1 μ m), become one of major reason of restriction silicon based opto-electronics integrated technology development.Therefore, development high efficiency, high-speed silicon-based nano opto-electronic conversion theory and method, it is most important to promote the fast development of silicon chip glazing interconnection technique.
Early stage optical communicating waveband silicon based opto-electronics Detection Techniques are introduced defect level mainly based on destroying silicon lattice structure in the forbidden band, thereby improve the physical mechanism that silicon absorbs energy photons, and the realization means mainly contain utilizes high strength femto-second laser pulse irradiation SF
6Silicon face in the environment produces micro-structural (J.E.Carey; C.H.Crouch, M.Shen, and E.Mazur; " Visible and near-infrared responsivity offemtosecond-laser microstructured silicon photodiodes; " Opt.Lett.30,1773-1775,2005; Z.Huang, J.E.Carey, M.Liu, X.Guo; E.Mazur, and J.C.Campbell, " Microstructured silicon photodetector ", Appl.Phys.Lett.89; 033506,2006.), silicon ion injects (A.P.Knights, J.D.B.Bradley; S.H.Gou, and P.E.Jessop, " Silicon-on-insulator waveguide photodetector withself-ion-implantation-engineered-enhanced infrared response; " J.Vac.Sci.Technol.A24,783-786,2006; Han Peide, full silicon waveguide type photoelectric converter and manufacturing approach thereof, number of patent application: 200710121973.0), the helium ion injects (Y.Liu; C.W.Chow, W.Y.Cheung, and H.K.Tsang; " In-line channel power monitor based on helium ion implantation insilicon-on-insulator waveguides, " IEEE Photonics Technol.Lett.18,1882-1884; 2006.), and low temperature depositing polysilicon (K.Preston, Y.H.D.Lee; M.Zhang, and M.Lipson, " Waveguide-integrated telecom-wavelength photodiode in deposited silicon; " Opt.Lett.36,52-54,2011.) etc. method.Though silicon is necessarily strengthened in the optical communicating waveband absorptivity, lattice defect causes the photodetector dark current excessive, and therefore, this technology is not very effectively.Utilize two photon absorption effect (T.K.Liang, H.K.Tsang, I.E.Day; J.Drake, A.P.Knights, and M.Asghari; " Silicon waveguide two-photon absorption detector at 1.5 μ m wavelengthfor autocorrelation measurements; " Appl.Phys.Lett.81,1323-1325,2002; T.Tanabe, H.Sumikura, H.Taniyama; A.Shinya, and M.Notomi, " All-silicon sub-Gb/stelecom detector with low dark current and high quantum efficiency on chip; " Appl.Phys.Lett.96,101103,2010.); Also can realize the absorption of silicon, but nonlinear effect requires the high power input or in the resonant cavity of high quality factor, just can realize near infrared band.In recent years, mix integrated low energy gap germanium (see the summary J.Michel, J.Liu, and L.C.Kimerling, " High-performance Ge-on-Siphotodetectors; " Nat.Photonics 4,527-534,2010.) or III-V family semiconductor (D.Liang, A.W.Fang; H.-W.Chen, M.N.Sysak, B.R.Koch, W.Lively; O.Raday, Y.-H.Kuo, R.Jones, and J.E.Bowers; " Hybrid silicon evanescent approach to opticalinterconnects, " Appl.Phys.A 95,1045-1057,2009; Z.Sheng, L.Liu.J.Brouckaert, S.He; And D.Van Thourhout, " InGaAs PIN photodetectors integrated onsilicon-on-insulator waveguides, " Opt.Express 18; 1756-1761; 2010.) etc. the absorbing material of having chance with to the silicon waveguide loop, and constructing the evanescent wave CGCM, to carry out the technical development of photodetection rapid, its photodetection performance can be equal to commercial detector mutually.Yet too rely on expensive germanium or III-V family semi-conducting material, require harsh film growth, bonding technology.
A kind of feasible scheme is to utilize interior lights emission (Internal Photoemission, IPE) mechanism: construct Schottky diode structure at metal-semiconductor interface, after metal electron absorbed incident light, self-energy was able to promote.If electron energy is greater than Schottky barrier, and, get in the semiconductor, collected by electrode and form photoelectric current just this excitation electron can be crossed Schottky barrier towards this interface motion.Photon energy just can be surveyed by Schottky diode greater than Schottky barrier.Yet therefore the low photoelectric respone degree also very low (mA/W magnitude even littler) that causes this detector of interior lights emission effciency, improves IPE efficient, develops high performance silica-based near-infrared photodetection theory and method and has very important practical significance.
IPE is a kind of physical effect that occurs on the metal-semiconductor interface.In semiconductor, make up Fabry-Paro resonant cavity (M.Casalino, L.Sirleto, L.Moretti; M.Gioffre, G.Coppola, and I.Rendina; " Silicon resonant cavity enhanced photodetector based on the internalphotoemission effect at 1.55 μ m:Fabrication and characterization, " Appl.Phys.Lett.92,251104; 2008.), perhaps dielectric waveguide structure (M.Casalino, L.Sirleto; M.Iodice, N.Saffioti, M.Gioffre; I.Rendina, and G.Coppola, " Gu/p-Si Schottky barrier-basednear infrared photodetector integrated with a silicon-on-insulator waveguide; " Appl.Phys.Lett.96,241112,2010; S.Zhu, M.B.Yu, G.Q.Lo; And D.L.Kwong, " Near-infrared waveguide-based nickel silicide Schottky-barrier photodetector foroptical communications, " Appl.Phys.Lett.92; 081103; 2008.), all non-method that directly acts on IPE, so reinforced effects is limited.In recent years, along with the development of nano preparation technique, (Surface Plasmon Polaritons, understanding SPPs) is more and more deep to being present in surface plasma excimer on the metal-dielectric interface for people.SPPs can also can be present in the scope of metal-dielectric interface nanometer scale with mode of resonance with the form of ripple, has extremely strong electric field strength.If SPPs is incorporated on the Schottky contacts face of Schottky diode, utilize the interaction between SPPs and the IPE, IPE efficient must be greatly improved.Yet the shooting condition of SPPs is very harsh, has intrinsic wavelength sensitive and Polarization-Sensitive characteristic, influences the optic response bandwidth and the polarization response characteristic (M.Fukuda of photodetection; T.Aihara, K.Yamaguchi, Y.Y.Ling; K.Miyaji, and M.Tohyama, " Light detection enhanced bysurface plasmon resonance in metal film; " Appl.Phys.Lett.96,153107,2010; M.W.Knight, H.Sobhani, P.Nordlander, and N.J.Halas, " Photodetection with activeoptical antennas, " Science 332,702-704,2011.), be unfavorable for practical application.Since 2009, people are successively at theoretical (A.Akbari, and P.Berini; " Schottky contact surface-plasmondetector integrated with an asymmetric metal strip waveguide; " Appl.Phys.Lett.95,021104,2009; C.Scales, I.Breukelaar, and P.Berini, " Surface-plasmon Schottkycontact detector based on a symmetric metal strip in silicon; " Opt.Lett.35,529-531,2010.) and experiment (A.Akbari; R.Niall Tait, and P.Berini, " Surface plasmon waveguideSchottky detector; " Opt.Express 18,8505-8514,2010; I.Goykhman, B.Desiatov, J.Khurgin; J.Shappir, and U.Levy, " Locally oxidized silicon surface-plasmonSchottky detector for telecom regime; " Nano Lett.11,2219-2224,2011.) the clear Schottky diode structure of leading based on surface plasma wave of Shanghai Stock Exchange can effectively improve IPE efficient; And the photoelectric respone bandwidth covers whole near infrared band, has effectively overcome the intrinsic wavelength sensitive characteristic of SPPs.But; These surface plasma wave guide structures are only supported horizontal magnetic (Transverse Magnetic; TM) polarization mode, and do not support transverse electric (Transverse Electronic, TE) polarization mode; Therefore, the photoelectric respone under the situation of TE polarised light input of this detector obviously is inferior to the situation of TM polarised light input.In addition, the active region of this detector must could fully absorb incident light by long enough (tens microns), produces enough big photoelectric current, and integrated degree remains further to be improved.
Summary of the invention
The purpose of the utility model is the deficiency to prior art, proposes a kind of near infrared band total silicon base nano photoelectric detector.
Near infrared band total silicon base nano photoelectric detector comprises substrate, silicon nanowires fiber waveguide, schottky junctions touched electrode, Ohm contact electrode and insulating barrier; In substrate, construct the silicon nanowires fiber waveguide; The schottky junctions touched electrode covers the top and the sidewall of silicon nanowires fiber waveguide; Be coated with insulating layer coating between silicon nanowires fiber waveguide and the schottky junctions touched electrode, the place at a distance of schottky junctions touched electrode 1～2 μ m in the flat board district of silicon nanowires fiber waveguide is provided with Ohm contact electrode, and incident light is imported from the silicon nanowires fiber waveguide; Be absorbed in the Schottky contacts zone; Be converted into photo-generated carrier through interior lights emission effect, collected the formation photoelectric current, realize opto-electronic conversion by schottky junctions touched electrode and Ohm contact electrode.
The beneficial effect that the utlity model has is:
1. the utility model adopts the IPE effect of Schottky diode, has overcome that wide bandgap semiconductor silicon does not absorb near infrared light and the physical restriction that can't make total silicon base photodetector.Device architecture is simple, can adopt CMOS technology to prepare fully, and is with low cost.
2. the utility model combines the interaction of IPE and SPPs, utilizes the strong local characteristic of SPP ripple to photon energy, has increased substantially photonic absorbance, and therefore, device architecture can be very little and do not influence its photoelectric conversion efficiency.
3. the basic configuration of the utility model is based upon on plated silicon nanowires fiber waveguide basis of polarization insensitive, has the good photoelectric response characteristic of super large bandwidth and polarization insensitive, can on silicon chip, be used widely in the optical interconnection system.
Description of drawings
Fig. 1 is the structural representation of near infrared band total silicon base nano photoelectric detector;
Fig. 2 is the photoelectric respone curve of near infrared band total silicon base nano photoelectric detector under TE/TM polarised light input condition, and illustration is an optical absorption spectra.
Embodiment
Below in conjunction with accompanying drawing and embodiment the utility model is described further.
As shown in Figure 1; Near infrared band total silicon base nano photoelectric detector comprises substrate 1, silicon nanowires fiber waveguide 2, schottky junctions touched electrode 3, Ohm contact electrode 4 and insulating barrier 5; In substrate 1, construct silicon nanowires fiber waveguide 2, schottky junctions touched electrode 3 covers the top and the sidewall of silicon nanowires fiber waveguide 2, is coated with insulating layer coating 5 between silicon nanowires fiber waveguide 2 and the schottky junctions touched electrode 3; Position at a distance of schottky junctions touched electrode 31～2 μ m in the flat board district of silicon nanowires fiber waveguide 2 is provided with Ohm contact electrode 4; Incident light is absorbed in the Schottky contacts zone from 2 inputs of silicon nanowires fiber waveguide, is converted into photo-generated carrier through interior lights emission effect; Collected the formation photoelectric current by schottky junctions touched electrode 3 and Ohm contact electrode 4, realize opto-electronic conversion.
Incident photon energy need only be higher than Schottky barrier and can be detected by this detector, has effectively overcome wide bandgap semiconductor silicon because of near infrared light not being absorbed the physical restriction that can't make total silicon base photodetector.The schottky junctions touched electrode must enough thinly can be come back reflective so that caught the electronics (hole) of photon energy between non-Schottky contacts face and Schottky contacts face, improve transition probability, reaches the purpose that improves internal quantum efficiency and photoelectric conversion efficiency.Insulating barrier is used to reduce the contact area between schottky junctions touched electrode and the silicon nanowires fiber waveguide, thereby reduces detector dark current.The photoelectric response characteristic of detector depends on the design feature of silicon nanowires fiber waveguide and schottky junctions touched electrode.The utility model adopts metal electrode to cover the structural design of silicon nanowires fiber waveguide top and sidewall; Not only has very large transmission bandwidth; Also support the TM/TE polarization mode, therefore, have the good response characteristic of super large bandwidth and polarization insensitive based on the detector of this structure.
Provide a specific embodiment of the utility model below.The wide 400nm of silicon nanowires fiber waveguide, the high 250nm of ridge, the dull and stereotyped thick 50nm in district, doping type can be N type or P type; Metal electrode selects for use 20nm thick, the gold that 4 μ m are long; Select for use the thick SU-8 of 50nm as insulating barrier.
Computing formula
can obtain the detector dark current size.In the formula, C
AreaBe the Schottky contacts area, A
*Be that (the gloomy constant of effective Richard in electronics and hole is respectively 112 and 32Acm to the gloomy constant of effective Richard
-2K
-2), Φ
BBe schottky barrier height (schottky barrier height that constitutes between gold-N type silicon and gold-P type silicon be respectively 0.8 and 0.34eV), k
BBe Boltzmann constant, T is an absolute temperature.If adopt P type silicon nanowires fiber waveguide to make the Schottky detector, the dark current under the room temperature is 156nA.Mix if fiber waveguide is replaced by the N type,,, 0.01pA is only arranged so dark current can reduce greatly because the Schottky barrier between gold-N type silicon is higher.
Photoelectric conversion efficiency can obtain through internal quantum efficiency, promptly
Wherein, A is a photon absorption efficiency, can calculate through the Finite Difference-Time Domain separating method, and q is an electronic charge, E
0Be incident photon energy, internal quantum efficiency η
iDepend on the IPE emission probability, promptly
Emission probability does
Wherein
The expression carrier energy is reduced to the number of times that in metal, moves back and forth before the Schottky barrier, P
k=P (E
k) the expression energy is E
kThe emission probability of charge carrier, specifically can be expressed as:
(when
The time), L is the attenuation length of the charge carrier in the metal, t is the schottky metal thickness of electrode.
Shown in Figure 2 is the photoelectric respone curve of an embodiment under TE/TM polarised light condition of incidence of the utility model, and illustration is an optical absorption spectra.Curve shows among the figure, and this detector can have tangible photoelectric respone at the near infrared band that energy is lower than the silicon energy gap, covers overall optical communication band (1.2-1.6 μ m), and in this scope, does not see tangible Polarization-Sensitive characteristic.The P type of silicon nanowires fiber waveguide is doped with to be beneficial to gold electrode and forms the low Schottky diode structure of barrier height, therefore, and the situation that photoelectric conversion efficiency is mixed far above the N type.
Claims (1)
1. near infrared band total silicon base nano photoelectric detector; It is characterized in that; Comprise substrate (1), silicon nanowires fiber waveguide (2), schottky junctions touched electrode (3), Ohm contact electrode (4) and insulating barrier (5); In substrate (1), construct silicon nanowires fiber waveguide (2), schottky junctions touched electrode (3) covers the top and the sidewall of silicon nanowires fiber waveguide (2), is coated with insulating layer coating (5) between silicon nanowires fiber waveguide (2) and the schottky junctions touched electrode (3); Place at a distance of schottky junctions touched electrode (3) 1～2 μ m in the flat board district of silicon nanowires fiber waveguide (2) is provided with Ohm contact electrode (4); Incident light is absorbed in the Schottky contacts zone from silicon nanowires fiber waveguide (2) input, is converted into photo-generated carrier through interior lights emission effect; Collected the formation photoelectric current by schottky junctions touched electrode (3) and Ohm contact electrode (4), realize opto-electronic conversion.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102569485A (en) * | 2011-12-31 | 2012-07-11 | 浙江大学 | Near-infrared band full silicon-base nanometer photoelectric detector |
| CN103022215A (en) * | 2012-12-26 | 2013-04-03 | 中国科学院微电子研究所 | Silicon-based germanium epitaxial structure and application thereof |
| CN105206686A (en) * | 2015-08-31 | 2015-12-30 | 电子科技大学 | Optical waveguide detector capable of eliminating parasitic capacitance |
| CN109655975A (en) * | 2019-01-16 | 2019-04-19 | 浙江大学 | A kind of erasable integrated light guide monitoring devices based on phase-change material |
| CN112688160A (en) * | 2020-12-24 | 2021-04-20 | 南方科技大学 | Wide bandgap semiconductor device and preparation method thereof, detector and modulator |
-
2011
- 2011-12-31 CN CN2011205748241U patent/CN202405298U/en not_active Withdrawn - After Issue
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102569485A (en) * | 2011-12-31 | 2012-07-11 | 浙江大学 | Near-infrared band full silicon-base nanometer photoelectric detector |
| CN102569485B (en) * | 2011-12-31 | 2014-12-31 | 浙江大学 | Near-infrared band full silicon-base nanometer photoelectric detector |
| CN103022215A (en) * | 2012-12-26 | 2013-04-03 | 中国科学院微电子研究所 | Silicon-based germanium epitaxial structure and application thereof |
| CN103022215B (en) * | 2012-12-26 | 2015-11-18 | 中国科学院微电子研究所 | A kind of silicon germanium epitaxial structure and preparation method thereof |
| CN105206686A (en) * | 2015-08-31 | 2015-12-30 | 电子科技大学 | Optical waveguide detector capable of eliminating parasitic capacitance |
| CN105206686B (en) * | 2015-08-31 | 2017-04-19 | 电子科技大学 | Optical waveguide detector capable of eliminating parasitic capacitance |
| CN109655975A (en) * | 2019-01-16 | 2019-04-19 | 浙江大学 | A kind of erasable integrated light guide monitoring devices based on phase-change material |
| CN109655975B (en) * | 2019-01-16 | 2020-12-08 | 浙江大学 | Erasable integrated optical waveguide monitoring device based on phase-change material |
| CN112688160A (en) * | 2020-12-24 | 2021-04-20 | 南方科技大学 | Wide bandgap semiconductor device and preparation method thereof, detector and modulator |
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Granted publication date: 20120829 Effective date of abandoning: 20141231 |
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