Dark current characteristics of GaAs metal-semiconductor-metal (MSM) photodetectors

ABSTRACTWe experimentally study the dark and photocurrent in metal-semiconductor-metal (MSM) photodetectors based on single-walled carbon nanotube film Schottky contacts on GaAs. We find that above ∼260°K, thermionic emission of electrons with a barrier height of ∼0.54 eV is the dominant dark current transport mechanism. Furthermore, MSM devices with CNT film electrodes exhibit a higher photocurrent-to-dark current ratio while maintaining a comparable responsivity relative to control devices. This work demonstrates that nanotube films can be integrated as Schottky electrodes in conventional semiconductor optoelectronic devices.

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A Theoretical and Experimental Comparison of 4H- and 6H-SiC MSM UV Photodetectors

Materials Science Forum ◽

10.4028/www.scientific.net/msf.717-720.1207 ◽

2012 ◽

Vol 717-720 ◽

pp. 1207-1210

Author(s):

Jang Kwon Lim ◽

Ludwig Östlund ◽

Qin Wang ◽

Wlodek Kaplan ◽

Sergey A. Reshanov ◽

...

Keyword(s):

Dark Current ◽

Experimental Comparison ◽

Metal Electrodes ◽

Current Ratio ◽

Uv Photodetectors ◽

Rejection Ratio ◽

Uv Illumination ◽

Metal Semiconductor Metal ◽

Msm Photodetectors ◽

High Rejection

This paper reports on fabrication and modeling of 4H- and 6H-SiC metal-semiconductor-metal (MSM) photodetectors (PDs). MSM PDs have been fabricated on 4H-SiC and 6H-SiC epitaxial layers, and their performance analyzed by MEDICI simulation and measurements. The simulations were also used to optimize the sensitivity by varying the width and spacing of the interdigitated electrodes. The fabricated PDs with 2 µm wide metal electrodes and 3 µm spacing between the electrodes exhibited, under UV illumination, a peak current to dark current ratio of 105 and 104 in 4H-SiC and 6H-SiC, respectively. The measured spectral responsivity of 6H-SiC PDs was higher compared to that of 4H-SiC PDs, with a cutoff at 407 nm compared to 384 nm in 4H-SiC PDs. Also the peak responsivity occurred at a shorter wavelength in 6H material. A high rejection ratio between the photocurrent and dark current was found in both cases. These experimental results were in agreement with simulation.

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Integrated MSM-FET Photoreceiver Fabricated on Mocvd Grown Hg1-xCdxTe

MRS Proceedings ◽

10.1557/proc-216-11 ◽

1990 ◽

Vol 216 ◽

Author(s):

Patrick W. Leech ◽

Peter J. Gwynn ◽

Geoffrey N. Pain ◽

Novica R. Petkovic ◽

James Thompson ◽

...

Keyword(s):

Dark Current ◽

Field Effect Transistor ◽

Gaas Substrates ◽

Integrated Devices ◽

Metal Semiconductor Metal ◽

Initial Work ◽

Effect Transistor ◽

Lift Off ◽

Msm Photodetectors ◽

Photoconductive Detector

ABSTRACTWe report on progress in the monolithic integration of a metal-semiconductor-metal (MSM) detector and transimpedence amplifier and of a photoconductive detector (PCD) with a metal-semiconductor field effect transistor (MESFET) in Hg1-xCdxTe. The layers of CdTe/n-type Hg1-xCdxTe were grown by MOCVD on semi-insulating GaAs substrates (2° misoriented 100). Fabrication of the devices was by an FET planar process; with a standard lift-off used to form Schottky metallization on both the interdigitated electrodes of the MSM detector (2μm width, 2μm spacing) and the gate of the MESFETs (5μm length, 100μm width). The MSM photodetectors exhibited breakdown voltages in the range 60 to 80V, a dark current of 1 Ona at 5V bias, and responsivities of > 1.0 A/W measured at 40V using CW 1.3um illumination. The integrated devices have been characterised by electrical and micro RBS techniques; the results were found to be strongly dependent on the stoichiometric x ratio of the Hg1-xCdxTe. This initial work demonstrates the suitability of Hg1-xCdxTe/GaAs structures in the fabrication of integrated optoelectronic circuits.

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Current Transport Mechanisms for MSM-Photodetectors on ZnO:N Thin Films

MRS Proceedings ◽

10.1557/proc-1201-h05-41 ◽

2009 ◽

Vol 1201 ◽

Author(s):

Tingfang Yen ◽

Alan Haungs ◽

Sung Jin Kim ◽

Alexander Cartwright ◽

Wayne A. Anderson

Keyword(s):

Thin Films ◽

Ion Implantation ◽

Dark Current ◽

Rf Sputtering ◽

Current Transport ◽

Transport Mechanisms ◽

Temperature Dependent ◽

Metal Semiconductor Metal ◽

Current Voltage ◽

Msm Photodetectors

AbstractMetal-semiconductor-metal photodetectors (MSM-PDs) on ZnO:N thin films deposited by radiofrequency (RF) sputtering and with post N+ ion implantation processing were fabricated using a ZnO/Si structure. A 10 times reduction in dark current was observed compared to the devices on an as-deposited ZnO thin film without ion implantation. These MSM-PDs gave performances of a photo-to-dark current ratio of 2030 and responsivity (R) = 2.7 A/W; the pulse response was a 12.3 ns rise time and 15.1 ns fall time using a femto-second pulse. Temperature-dependent current -voltage (I-V-T) characteristics of the MSM-PDs were observed and the space charge limited current (SCLC) theory was applied to determine the current transport mechanisms. In the SCLC region, J∼Vm gave m to determine the current transport mechanism and the value of m changes with temperatures and applied voltages. Current transport is governed by the ZnO structure rather than the electrodes.

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Suppression of dark current in GeO_x-passivated germanium metal-semiconductor-metal photodetector by plasma post-oxidation

Optics Express ◽

10.1364/oe.23.016967 ◽

2015 ◽

Vol 23 (13) ◽

pp. 16967 ◽

Cited By ~ 13

Author(s):

Jian Kang ◽

Rui Zhang ◽

Mitsuru Takenaka ◽

Shinichi Takagi

Keyword(s):

Dark Current ◽

Metal Semiconductor Metal

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THE STUDY OF Pd SCHOTTKY CONTACT ON POROUS GaN FOR UV METAL–SEMICONDUCTOR–METAL (MSM) PHOTODETECTORS

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s0218863507003871 ◽

2007 ◽

Vol 16 (04) ◽

pp. 497-503 ◽

Cited By ~ 1

Author(s):

L. S. CHUAH ◽

Z. HASSAN ◽

H. ABU HASSAN

Keyword(s):

Molecular Beam Epitaxy ◽

Tensile Stress ◽

Molecular Beam ◽

Schottky Contact ◽

Nitrogen Plasma ◽

Porous Sample ◽

Optical Studies ◽

High Quality ◽

Metal Semiconductor Metal ◽

Msm Photodetectors

High quality unintentionally doped n-type GaN layers were grown on Si (111) substrate using AlN (about 200 nm) as buffer layer by radio frequency (RF) nitrogen plasma-assisted molecular beam epitaxy (MBE). This paper presents the structural and optical studies of porous GaN sample compared to the corresponding as-grown GaN. Metal–semiconductor–metal (MSM) photodiode was fabricated on the samples. For as-grown GaN-based MSM, the detector shows a sharp cut-off wavelength at 362 nm, with a maximum responsivity of 0.254 A/W achieved at 360 nm. For porous GaN MSM detector, a sharp cut-off wavelength at 360 nm with a maximum responsivity of 0.655 A/W was achieved at 359 nm. Both the detectors show a little decrease in responsivity in the UV spectral region. The MSM photodiode based on porous GaN shows enhanced (2×) magnitude of responsivity relative to the as-grown GaN MSM photodiode. Enhancement of responsivity can be attributed to the relaxation of tensile stress and reduction of surface pit density in the porous sample.

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