Depletion region

About: Depletion region is a research topic. Over the lifetime, 9393 publications have been published within this topic receiving 145633 citations.

Surface photovoltage measurements on pyrite (100) cleavage planes: Evidence for electronic bulk defects

Abstract: Temperature dependent contactless surface photovoltage measurements by photoelectron spectroscopy have been performed on cleaved (100) surfaces of pyrite (FeS2) single crystals. The results have been fitted by thermionic emission, recombination, and tunneling models for the majority carrier transport to the surface. Neither of them is able to explain the small photovoltages consistently. By calculating electronic defect levels due to the sulfur deficiency of pyrite a high number of defect states in the band gap is obtained. As a consequence a nonuniform depletion layer is expected with a part of the band bending potential falling off at a very small distance near the surface. The small photovoltages can be explained by a tunneling of majority carriers through the narrow barrier and by recombination losses due to the defects.

Analysis of the forward and reverse bias I-V and C-V characteristics on Al/PVA:n-PbSe polymer nanocomposites Schottky diode

Abstract: This paper presents the fabrication and characterization of the Al/PVA:n-PbSe Schottky diode I-V characteristics have been measured at different temperatures in the forward bias The behavior study of the series resistance (RS), the ideality factor (n), the effective barrier height (Φb), the Richardson constant (A*), and the leakage current with the temperature have emphasized an inhomogeneity of the barrier height and a tunneling mechanism assisted by traps in the SBD In C-V measurements, in the reverse bias, the Al/PVA:n-PbSe has been performed as a function of temperature and frequency The values of barrier height (ΦC-V), the built-in–voltage (Vbi) and carrier concentration (ND) and depletion layer width (W) have been calculated at different temperatures in reverse bias The barrier inhomogeneities of the Al/PVA:n-PbSe contact has been explained on an assumption of a Gaussian distribution of barrier heights by using the potential fluctuation model

Surface depletion in doped SrTiO3 thin films

Abstract: Strong effects of surface depletion have been observed in metallic La-doped SrTiO3 thin films grown on SrTiO3 substrates by pulsed-laser deposition. The depletion layer grows with decreasing temperature due to the large temperature-dependent dielectric response of SrTiO3. When the depletion layer becomes comparable to or exceeds the thickness of the doped film, the Hall mobility shows significant enhancements as more of the electron distribution extends into the undoped substrate, in conceptual analogy to modulation doping in compound semiconductor heterostructures.

Aging Mechanisms of InGaN/AlGaN/GaN Light-Emitting Diodes Operating at High Currents

Abstract: Changes of luminescence spectra and electrical properties of light-emitting diodes (LED’s) based on InGaN/AlGaN/GaN heterostructures were investigated over a long period of operation. Blue and green LED’s with InGaN single quantum wells were studied at currents up to 80 mA for 102−2.103 hours. An increase of luminescence intensity at operating currents of 15 mA was detected at the 1st stage of aging (100–800 hours) and a slow fall was detected in the 2nd stage. Greater changes of spectra were observed at low currents (< 0.15 mA). A study of charged acceptor distribution in the space charge region has shown that at the 1st stage their concentration grows, and in the 2nd stage, it falls. The models for the two stages are proposed: 1) activation of Mg due to destruction of residual Mg-H complexes; 2) formation of donor vacancies N. A model of defect formation by hot electrons injected into the quantum well is discussed.