Speed photodetectors based on amorphous and microcrystalline silicon p–i–n devices

Abstract

Selective epitaxial germanium on silicon-on-insulator high speed photodetectors using low-temperature ultrathin Si 0.8 Ge 0.2 buffer Appl. Phys. Lett. 91, 073503 (2007); 10.1063/1.2769750Amorphous selenium based photodetector driven by field emission current from N-doped diamond cold cathode

Optimized Laser Scanned Photodiode (LSP) Imaging Transducer

“…A light pattern projected onto an a-Si:H based p-i-n photodiode leads to a distortion of space charge regions at the junctions giving rise to a modulation of the potential barrier [10,11]. Low local potential barriers are ascribed to illuminated regions and high potential barriers to dark zones [12].…”

High-performance position-sensitive detector based on graphene–silicon heterojunction

“…[1][2][3][4][5][6][7][8][9][10] Due to the high mobility [13,14] of graphene, the diffusion length of holes in graphene is very long and the efficiency of signal collection at the electrodes could be greatly improved. In addition, graphene can also absorb light and produce photo-generated carriers, with electrons entering…”

“…[1][2][3][4][5][6][7][8][9][10] The photo-induced holes will diffuse, and the position of light could be determined by the difference in the photovoltage (or numbers of carriers) between the two electrodes. However, the defects, impurities and the surface states in Si would restrict the diffusion of holes, leading to a very short diffusion length.…”

“…[1][2][3][4][5][6][7][8][9] Silicon (Si) p-n or p-i-n junctions [2][3][4][5][6] are the most commonly used structures for current PSD. Photoexcited electron-hole (e-h) pairs are separated by built-in electric field at the junction, and the carriers diffuse in the surface layer and are collected by two terminal electrodes.…”

Transient lateral photovoltaic effect in patterned metal-oxide-semiconductor films

“…We have studied the transient photovoltaic effect (T-LPE) 4,16,17 as a response to turning the laser beam illumination on (steady state, referred to as the ON state) followed by switching the laser off (decaying regime, referred to as the OFF state) as a function of the spot position, pulse frequency, and power. We observe peak-like transitorials which present a sign inversion of the T-LPE in the OFF state followed by a nearly exponential relaxation back to equilibrium.…”