Molecular beam epitaxy growth of inp/ingaas structures for short wavelength infrared photodetectors

Temel, Oğuzhan
Indium Gallium Arsenide (In0.53Ga0.47As) is a suitable compound semiconductor for photodetector applications in the Short Wavelength Infrared (SWIR) band with its ~1.7 µm cut-off wavelength. In this work, lattice-matched InxGa1-xAs compounds (x~0.53) were grown on InP (001) substrates by the molecular beam epitaxy (MBE) method. Unintentional doping level as low as 1.96E15 cm-3 was obtained in the In0.53Ga0.47As epilayers. The X-ray diffraction full width at half maximum values were as low as 45 arc-sec displaying the high crystal quality of the epilayers. The device structures with the epilayers of n+InP/In0.53Ga0.47As/p+InP and n+InP/In0.53Ga0.47As/p+In0.52Al0.48As were grown, and their structural characterization was conducted. Test detectors with large area mesas (200x200 and 300x300 µm2) were fabricated with a non-optimized fabrication process for electrical and optical characterization. The aim of the characterization of the test detectors was to determine the material’s preliminary device performance. The peak responsivity of the test detectors was ~1 A/W at room temperature under 100 mV reverse bias. The corresponding quantum efficiency near the cut off wavelength is ~75%. The dark current of the test detectors under small reverse bias was dominated by the generation-recombination mechanism at room temperature. The dark current density of the test detectors with ~1.7 µm cut-off wavelength at 298 K (100 mV reverse bias) was 2.5 µA/cm2 with a fabrication process which has not been optimized yet.


Molecular beam epitaxial growth and characterization of extended short wavelength infrared mercury cadmium telluride detectors
Şaşmaz, Emrah; Beşikci, Cengiz; Department of Electrical and Electronics Engineering (2017)
This thesis reports the growth, fabrication and characterization of extended short wavelength infrared (SWIR) mercury cadmium telluride (Hg1-xCdxTe) photodiodes with a cut off wavelength of 2.17 µm at room temperature. HgCdTe layers were grown on home-polished cadmium zinc telluride, CdZnTe, substrates by molecular beam epitaxy (MBE). Test arrays were fabricated in order to evaluate the electrical and optical characteristics of the photodiodes. Test array consists of mesa type pixels with 30 µm pitch. The t...
High performance near/short wavelength infrared megapixel InGaAs focal plane array fabrication development and new design proposals
Karaca, Utku; Kocaman, Serdar; Department of Electrical and Electronics Engineering (2018)
In0.53Ga0.47As is the most appropriate material system for Short Wavelength Infrared (SWIR) detection at ~1.7 μm cutoff wavelength with its relatively lower cost and high performance. Ultra-low dark current (~ nA/cm2) has been recently demonstrated in InGaAs photodetectors with planar type process by eliminating surface leakage current. Here, a fabrication procedure for planar InGaAs photodetectors with unique pixel isolation methods has been developed and ~10 nA/cm2 dark current density levels were obtaine...
Molecular beam epitaxial growth of high quality InSb
Michel, E.; Singh, G.; Slivken, S.; Beşikci, Cengiz; Bove, P.; Ferguson, I.; Razeghı, M. (1994-12-26)
In this letter we report on the growth of high quality InSb by molecular beam epitaxy that has been optimized using reflection high energy electron diffraction. A 4.8 μm InSb layer grown on GaAs at a growth temperature of 395 °C and a III/V incorporation ratio of 1:1.2 had an x‐ray rocking curve of 158 arcsec and a Hall mobility of 92 300 cm2 V−1 at 77 K. This is the best material quality obtained for InSb nucleated directly onto GaAs reported to date.
Optical properties of TlGaxIn1-xS2 layered mixed crystals (0 <= x <= 1) I. Composition- and temperature-tuned energy band gap
Hasanlı, Nızamı (2010-05-28)
Optical properties of the TlGaxIn1-xS2 mixed crystals (0 <= x <= 1) have been studied by means of transmission and reflection measurements in the wavelength range of 400-1100 nm. The optical indirect band gap energies were determined through the analysis of the absorption data. It was found that the energy band gaps increase with increasing of gallium atoms content in the TlGaxIn1-xS2 mixed crystals. From the transmission measurements carried out in the temperature range of 10-300K, the rates of change of t...
Hasanlı, Nızamı; MELNIK, NN; RAGIMOV, AS (Wiley, 1983-01-01)
Measurements are made of polarized Raman scattering and infrared reflection spectra of twenty two compositions of GaS1‐xSex layer mixed crystals grown by the Bridgman method. Besides the usual one‐mode and two‐mode behaviours of phonon modes, a number of more complex dependences characterized by the appearance of additional bands in the spectra of mixed crystals are observed. Their appearance is accounted for by the uncovering of the Brillouin zone due to the disturbance of the periodicity of the crystal la...
Citation Formats
O. Temel, “Molecular beam epitaxy growth of inp/ingaas structures for short wavelength infrared photodetectors,” M.S. - Master of Science, Middle East Technical University, 2014.