Photoconductive gain of semiconductor epitaxial layers

Abstract

A model is proposed for the interpretation of the dependence of photoconductive gain (PG) of semiconductor epitaxial layers upon photon flux and absolute temperature. The model takes into account the macroscopic potential barrier existing within the interface of the epitaxial layer/substrate devices (ESD) as well as the current/voltage characteristic of the illuminated ESD.

Self‐Healing Cs3Bi2Br3I6 Perovskite Wafers for X‐Ray Detection

“…They provide an internal amplification mechanism, which is equivalent to photoconductive gain, [18,39,40] as is frequently reported for photodetectors operating in the visible spectral region. [41][42][43] The gain results from an imbalance between carrier drift time and carrier lifetime, which is favored in semiconductors with high trap state densities. A clear evidence for the presence of such an internal gain mechanism is given, when the measured sensitivity correlates to an electron-hole pair creation energy which is smaller than the band gap energy of the semiconductors, such as is the case for the high sensitivity X-ray detector reported in ref.…”

On Negative Differential Mobility in Nanophotonic Device Functionality

“…In Figure 1, the energy band depth-profile of a generichomointerface nanophotonics device is presented: The band bending occurs at the illuminated n-type upper semiconductor-layer's surface and within the nanodevice interface extending between the equilibrium parts of this epilayer and the relatively p-type-like lower semiconductor-layer. The nanointerface (NIF) potential-energy barrier eU b is equal to e(U bi -U ph ) , where U bi is the NIF diodic built-in voltage and U ph is the generated evolving photovoltage [2][3][4]7]. The photocurrent density J through the NIF consists of the space-charge-region photogeneration-current density J g , the current density J p (x) at the NIF upper-boundary locus x owing to hole diffusion from the n-type epilayer downwards, and the current density J n (x + w) at the NIF lower-boundary locus x + w owing to electron diffusion from the p-type sublayer upwards [1].…”

“…In this work, several instances [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20], in our two-decade principal research, of both experimental observation and conceptual prediction concerning NDM are reconsidered towards outlining a global potential for the appearance of the effect, the essence of which consists in the variation of the nanointerfacial two-dimentional electron gas's mobility becoming negative against further positive proper regulatory agent's (bias's, photonic dose's) change for some regulatory agent's value-interval(s).…”

On Radioactivity–Exposed Nanophotodetector Optoreliability

“…As, then, is well known [5][6][7], the dark saturationrecombination diodic current is at a given absolute sensor-ambient temperature determined by the dark depletion-zone built-in voltage value, indicatively measuring for commercial Si p-i-n photodiodes below 200 -300 nA against registered total conductivity-current values of units or tens of a μA through wide-range and high-level photonic fluxes. These facts render the directly measured overall conductivity-current permeating the photodetector nanointerface adequately approaching the net optoelectronic detection photocurrent I.…”