Assessment of InSb photodetectors on Si substrates

We present the detailed characteristics of small area (33 x 33 mum(2)) InSb photodiodes grown on GaAs coated Si substrates by molecular beam epitaxy. In spite of very large lattice mismatch, 80 K peak detectivity of similar to1 x 10(10) cm Hz(1/2) W-1 has been measured under backside illumination without anti-reflection coating. Differential resistance at 80 K is limited by Ohmic leakage under small reverse bias and trap assisted tunnelling (TAT) under moderately large reverse bias. In the temperature range of 80-140 K, the zero-bias resistance is considerably degraded by Ohmic leakage which has a small activation energy of 25 meV While the excess leakage seems to be related with the dislocations, the peak quantum efficiency is not considerably affected by the presence of dislocations. 80 K 1/f noise is dominated by TAT processes, and the noise current at 1 Hz follows the empirical relation i(n) = alpha(TAT)(I-TAT) with alpha(TAT) = 7.5 x 10(-7) and beta = 0.55. Bias dependence of the generation-recombination noise is discussed and compared with the predictions of Kleinpenning's mobility fluctuation model.


Photo-stimulated luminescence of calcium co-doped BaFBr : Eu2+ x-ray storage phosphors
SCHLAPP, M; Bulur, Enver; VON SEGGERN, H (IOP Publishing, 2003-01-21)
The influence of calcium co-doping on the optical properties of the x-ray storage phosphor BaFBr: Eu2+, is determined by photo- stimulated luminescence techniques. It is found that the incorporation of calcium into the lattice results in a broadening of the photo- stimulation peak due to a calcium induced FA(Br, Ca2+)-centre with stimulation maxima at 540 and 680 nm. The optical cross-sections for the photo- stimulated process are determined by utilizing stimulation light with linearly increasing intensity....
Perturbation analysis of sheath evolution, with application to plasma source ion implantation
Bektursunova, RM; Demokan, O (IOP Publishing, 2001-02-07)
A perturbation model has been developed to describe the evolution of an expanding plasma sheath around a cathode after a high-voltage negative pulse is applied to the cathode, simulating the conditions in devices such as those used for plasma source ion implantation. The set of governing equations consists of two coupled collisionless fluid equations for ions, and Poisson's equation and Boltzmann's assumption for electrons. The time-dependent, self-consistent expressions for the potential, ion density and i...
Design of a microbial sensor using conducting polymer of 4-(2,5-di(thiophen-2-yl)-1H-pyrrole-1-l) benzenamine
Tuncagil, Sevinc; ODACI DEMİRKOL, DİLEK; Yidiz, Ersin; TİMUR, SUNA; Toppare, Levent Kamil (Elsevier BV, 2009-03-28)
A microbial biosensor based on Gluconobacter oxydans cells immobilized on the conducting polymer of 4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)benzenamine (SNS-NH2) coated onto the Surface of graphite electrode was constructed. The proposed biosensor was characterized using glucose as the Substrate. The linear relation was observed in the range of 0.1-2.5 mM and defined by the equation y = 0.415x + 0.377 (R-2 = 0.986). Analytical characterization, effects of electropolymerization time, pH, cell amount and the ...
Medium band gap polymer based solution-processed high-kappa composite gate dielectrics for ambipolar OFET
Canimkurbey, Betul; Unay, Hande; Cakirlar, Cigdem; Buyukkose, Serkan; Çırpan, Ali; Berber, Savas; Parlak, Elif Alturk (IOP Publishing, 2018-03-28)
The authors present a novel ambipolar organic filed-effect transistors (OFETs) composed of a hybrid dielectric thin film of Ta2O5: PMMA nanocomposite material, and solution processed poly(selenophene, benzotriazole and dialkoxy substituted [1,2-b: 4, 5-b'] dithiophene (P-SBTBDT)-based organic semiconducting material as the active layer of the device. We find that the Ta2O5: PMMA insulator shows n-type conduction character, and its combination with the p-type P-SBTBDT organic semiconductor leads to an ambipo...
Investigation of localized levels in GaS0.5Se0.5 layered crystals by means of electrical, space-charge limited current and photoconductivity measurements
Qasrawi, AF; Hasanlı, Nızamı (Wiley, 2002-11-16)
To identify the localized levels in GaS0.5Se0.5 single crystals, the dark electrical conductivity, current-voltage characteristics and photoconductivity measurements were carried out in the temperature range of 250-400 K. Temperature dependence of dark electrical conductivity and the space-charge limited current studies indicate the presence of a single discrete trapping level located at 0.31 eV below the conduction band with a density of about 1.3 x 10(15) cm(-3). The conductivity data above 320 K reveal a...
Citation Formats
S. Ozer and C. Beşikci, “Assessment of InSb photodetectors on Si substrates,” JOURNAL OF PHYSICS D-APPLIED PHYSICS, pp. 559–563, 2003, Accessed: 00, 2020. [Online]. Available: