Query: Silicon photodiodes with high photoconductive gain at room temperature

Candidate papers:

abstract: Silicon photodiodes with high photoconductive gain are demonstrated. The photodiodes are fabricated in a complementary metal oxide semiconductor (CMOS) compatible process. The typical room temperature responsivity at 940 nm is >20 A/W and the dark current density is 100 nA/cm2 at 5 V reverse bias, yielding a detectivity of 10(14) Jones. These photodiodes are good candidates for applications that require high detection sensitivity and low bias operation.
author_names: Xiaojian Li

James E Carey

Jason William Sickler

Martin U Pralle

Chintamani P Palsule

Christopher J Vineis
title: Silicon photodiodes with high photoconductive gain at room temperature.
venue: Optics express
year: 2012

abstract: Abstract For the full benefit of the silicon chip industry and to further extend the photoresponse cut off wavelength of the current Si photodetectors beyond 1100 nm, high performance silicon compatible Mg2Si/Si n p photodiodes are constructed on the bulk silicon wafer by magnetron sputtering and post annealing sequential processes. The results show that the annealing period appreciably affects microstructure, crystallite size, and roughness of the Mg2Si film sputtered on glass substrates and silicon wafers. Meanwhile, the fabricated Mg2Si/Si n p photodiodes demonstrate clear rectifying behavior and evident spectral response characteristics in the wavelength domain from 0.8 to 1.35 mm, with a maximum room temperature zero bias response of 0.1, 0.15, 0.86, and 0.47 A/W at 1.05 mm for the annealing periods of 10, 20, 40, and 60 min, respectively. The photoresponse cut off wavelength of the fabricated Mg2Si/Si n p photodiodes is 1.35 mm; however, the photosensitive cut off of the commercially available Hamamatsu Si photodiode is 1.25 mm. The fabricated Mg2Si/Si n p photodiodes at RTA period of 40 min reveal spectral response of longer cut off wavelength and higher intensity near the photon energy threshold compared to the Hamamatsu Si photodiode. In this context, the fabricated photodiodes in this study offer huge potentials to develop high performance silicon compatible photodiodes for efficiently sensing the infrared light in the wavelength domain from 0.8 to 1.35 mm.
author_names: Ahmed A M El-Amir

Takeo Ohsawa

Satoshi Ishii

Masataka Imura

Meiyong Liao

Xiuwei Fu

Hiroyo Segawa

Isao Sakaguchi

Tadaaki Nagao

Kiyoshi Shimamura

Naoki Ohashi
title: Silicon compatible Mg2Si/Si n p photodiodes with high room temperature infrared responsivity
venue: Materials Science in Semiconductor Processing
year: 2019

abstract: In this Letter, we report large area (600 mm diameter) 4H SiC avalanche photodiodes (APDs) with high gain and low dark current for visible blind ultraviolet detection. Based on the separate absorption and multiplication structure, 4H SiC APDs passivated with SiNx instead of SiO2 are demonstrated for the first time, to the best of our knowledge. Benefitting from the SiNx passivation, the surface leakage current is effectively suppressed. At room temperature, high multiplication gain of 6.5x105 and low dark current density of 0.88 mA/cm2 at the gain of 1000 are achieved for our devices, which are comparable to the previously reported small area SiC APDs.
author_names: Zhou Xingye

Jia Li

Luo Weili

Yuangang Wang

Song Xubo

Shunzheng Yin

Tan Xin

Yuanjie Lu

Hongyu Guo

Guodong Gu

Zhihong Feng
title: Large area 4H SiC avalanche photodiodes with high gain and low dark current for visible blind ultraviolet detection
year: 2018

abstract: Avalanche gain and breakdown voltage in most wide bandgap semiconductor materials are dependent on temperature and most instruments utilizing APDs rely on temperature stabilization or voltage compensation circuitry to maintain a constant avalanche gain. The complexity in operation circuitry can be reduced by incorporating material with inherently superior temperature stability in its avalanche gain and breakdown voltage. In state of the art APDs, the temperature dependence of avalanche breakdown voltage is quantified by the temperature coefficient of avalanche breakdown, Cbd. We report on the temporal and temperature stability of avalanche gain and breakdown voltage of 100 nm thick avalanche layers of Al0.85Ga0.15As0.56Sb0.44 (AlGaAsSb) The Cbd (1.60 mV/K) is smaller compared to state of art InP and InAlAs APDs for similar avalanche layer thickness. The temporal stability of avalanche gain for the AlGaAsSb APD was also evaluated in temperature ranges of 294 K to 353 K. The APD was biased at room temperature gain of 10 and maximum fluctuation of 0.7% was recorded at 294 K which increases to 1.33% when the temperature was increased to 353K. The promising temperature stability of gain indicates the potential of AlGaAsSb lattice matched to InP in achieving higher tolerance to temperature fluctuations and reduction of the operational complexity of circuitry. The dark currents are robust and do not show significant thermal degradation after gain measurements at elevated temperatures.
author_names: S Zhang

Js S Ng
title: Al0.85Ga0.15As0.56Sb0.44 avalanche photodiodes with high immunity to temperature fluctuation
venue: NanoScience Engineering
year: 2018

abstract: A longwave infrared photodetector made of double layers of 100nm amorphous germanium (a Ge) and 25nm amorphous silicon (a Si) have been demonstrated. Under room temperature, the device shows the responsivity of 1.7 A/W, detectivity of 6x108 Jones, and noise equivalent power (NEP) of 5pW/Hz under 5V bias and at 20kHz operation. Studies of frequency dependent characteristics and device modeling indicate that, above 100Hz or beyond the bandwidth of thermal response, the device operates as a quantum detector having the photoelectrons produced by optical excitation from the bandtail states to the mobile states of a Ge. The superior device performance may be attributed to the combination of two amplification mechanisms: photoconductive gain in a Ge and cycling excitation process (CEP) in a Si, with the latter being the dominant factor. Besides its attractive performance, the device has a simple structure and is easy to fabricate at low cost, thus holding promise for night vision, sensing, autonomous driving, and many other applications.
author_names: Jiayun Zhou

Mohammad Abu Raihan Miah

Yugang Yu

Alex Ce Zhang

Zijian Zeng

Samir Damle

Iftikhar Ahmad Niaz

Yanan Zhang

Yu-hwa Lo
title: Room temperature long wave infrared detector with thin double layers of amorphous germanium and amorphous silicon.
venue: Optics express
year: 2019

abstract: Avalanche photodiodes (APD) are important components in short wave and mid wave infrared detection systems (imaging, laser radar, communications, etc. because their internal gain can improve receiver sensitivity and enables the detection of weak photon fluxes. The statistical nature of impact ionization in APDs contributes to excess shot noise, however. The excess noise factor, F(M) is related to the ratio of the electron and hole ionization coefficients, k, and multiplication, M, by F(M) ;M<;sup>2</sup>;M>;sup>2</sup> k<;M> (1 k)(2 1/;M> In the mid infrared, HgCdTe APDs represent the current state of the art; at liquid nitrogen temperatures, advanced devices offer excellent low noise characteristics with F(M) 1, gains of >1000, and excellent dark currents. Unfortunately, devices that operate at shorter wavelengths exhibit degraded noise characteristics and significantly lower maximum gains ;30. This, when combined with the growth and fabrication challenges associated with II VI compounds has motivated the search for alternative APD materials. InAs APDs, which offer a shorter wavelength cutoff wavelength of ~3 mm, have recently been found to exhibit F(M) 1, with moderately low dark current at room temperature. Increasing the multiplication region thickness increases the gains achievable at low bias, which is beneficial for integration with Read Out Integrated Circuits (ROICs) Therefore, to design a high gain InAs APD, a thick multiplication region is required. This, in turn, necessitates extremely low background doping ;1015 cm 3) or appropriate counter doping, in order to realize complete depletion and a uniform electric field profile. In this paper, we report record high gain InAs APDs employing 6 mm thick and 10 mm thick intrinsic regions with low background doping of ~4x1014 cm 3, as determined by C V profiling. An AlAsSb blocking layer was used in both structures to suppress electron diffusion current, the dominant dark current mechanism at room temperature. Significant reduction in dark current were critical to characterize these thicker multiplication regions at high gain, resulting in record high room temperature multiplication gain of ~300 at 15 V bias. This is ~6x the previous record for InAs of 50 at 15 V, as well as significantly higher than the maximum gain of 126 reported at higher biases, and represents a significant step forward in InAs APD performance.
author_names: Wenlu Sun

Scott J Maddox

Seth R Bank

Joe C Campbell
title: Record high gain from InAs avalanche photodiodes at room temperature
venue: 72nd Device Research Conference
year: 2014

abstract: We successfully demonstrate the high stability at room temperature of a new design of single photon detector based on multiple tunnel junctions with superior responsivity and high quantum efficiency. The single photon detector uses one dimensional (1D) multiple tunnel junctions (MTJs) with 12 islands and 13 tunnel junctions coupled with a silicon single electron box. A single electron transistor (SET) is used to read the charge state of a silicon quantum dot (Si QD) The response of the single photon detector (Si QD and SET) is directly related to the photoconductivity gain in the MTJs with associated conductance steps produced by individual photocarriers. Numerical simulations confirm the high stability at room temperature of the single photon detection. Moreover, an analytical model developed in MATLAB that takes account of the thermionic emission of charge carriers confirms the high stability of the single photon detection at room temperature.
author_names: Amine Touati

S Chatbouri

Adel Kalboussi
title: Room temperature high sensitivity of multiple tunnel junctions based on single charge photodetection
venue: Journal of Computational Electronics
year: 2019

abstract: We report Al<sub>0.8</sub>In<sub>0.2</sub>As<sub>0.23</sub>Sb<sub>0.77</sub> avalanche photodiodes with high gain <inline formula> <tex math notation="LaTeX"$M>1300$ /tex math>/inline formula> and low dark current at room temperature. Impact ionization coefficients for this material system are also extracted, indicating electron dominant impact ionization. Low avalanche breakdown temperature dependence is demonstrated.
author_names: Andrew H Jones

Ann Kathryn Rockwell

Stephen D March

Yuan Yuan

Seth R Bank

Joe C Campbell
title: High Gain, Low Dark Current Al0.8In0.2As0.23Sb0.77 Avalanche Photodiodes
venue: IEEE Photonics Technology Letters
year: 2019

abstract: Using our computer programs, numerical simulations of photoelectric and fluctuating phenomena were carried out in diode structures of the CdHgTe mesa in the P+n(p)N+ configuration operating at 230 K and 300 K. These phenomena were analyzed in structures where additional energy barriers at the absorber boundary were applied. Exclusion and extraction of charge carriers in the absorber area after biasing the structures with reverse voltage reduces their concentration by more than an order of magnitude. Reduction of carrier concentration has a positive effect on the increase of the absorption coefficient due to reduction of the Burstein Moss effect, increases the resistance and electro optical gain, and effectively suppresses generation and thermal recombination. It is possible to obtain 70% of quantum efficiency in biased photodiodes. It was shown that a non equilibrium long wave photodiode working at room temperature can have a normalized detectivity of over 109 cmHZ1/2W 1 for radiation with 10.6 mm wavelength. The results of our calculations and their analysis are illustrated by numerous figures.
author_names: Krzysztof Jozwikowski

Alina Jozwikowska
title: Enhanced Numerical Modeling of HgCdTe Long Wavelength Infrared Radiation High Operating Temperature Non equilibrium P+n(p)N+ Photodiodes
venue: Journal of Electronic Materials
year: 2019

abstract: Abstract We report on the growth of high quality GaSb based AlInAsSb quaternary alloy by molecular beam epitaxy (MBE) to fabricate avalanche photodiodes (APDs) By means of high resolution X ray diffraction (HRXRD) and scanning transmission electron microscope (STEM) phase separation phenomenon of AlInAsSb random alloy with naturally occurring vertical superlattice configuration was demonstrated. To overcome the tendency for phase segregation while maintaining a highly crystalline film, a digital alloy technique with migration enhanced epitaxy growth method was employed, using a shutter sequence of AlSb, AlAs, AlSb, Sb, In, InAs, In, Sb. AlInAsSb digital alloy has proved to be reproducible and consistent with single phase, showing sharp satellite peaks on HRXRD rocking curve and smooth surface morphology under atomic force microscopy (AFM) Using optimized digital alloy, AlInAsSb separate absorption, grading, charge, and multiplication (SAGCM) APD was grown and fabricated. At room temperature, the device showed high performance with low dark current density of ~14.1 mA/cm 2 at 95% breakdown and maximum stable gain before breakdown as high as ~200, showing the potential for further applications in optoelectronic devices.
author_names: Lyu Yuexi

Xi Han

Yao-yao Sun

Zhi Jiang

Chun-yan Guo

W F Xiang

Yinan Dong

Jie Cui

Yuan Yao

Dong-wei Jiang

Guo-wei Wang

Ying-qiang Xu

Zhichuan Niu
title: Digitally grown AlInAsSb for high gain separate absorption, grading, charge, and multiplication avalanche photodiodes
year: 2018