1c:I[419806,["/_next/static/chunks/bb923814e1f4d2e9.js","/_next/static/chunks/dd3ee9f5b7716ca6.js","/_next/static/chunks/4204a0ae82542ca8.js","/_next/static/chunks/1270dead247da766.js","/_next/static/chunks/6e1aa89a642f40be.js","/_next/static/chunks/cd5e572bc3e4eb92.js","/_next/static/chunks/8ffd0b71567920d8.js","/_next/static/chunks/67ea6dfd21f16c5f.js","/_next/static/chunks/24eb4379f68013fd.js","/_next/static/chunks/b8cd775ffdf935bd.js","/_next/static/chunks/983103cd9eb7b428.js","/_next/static/chunks/d4ac9dcf27f6ff52.js","/_next/static/chunks/294b9525248c8e5f.js"],"default"] 1d:T51c,The concept of homojunction internal photoemission far-infrared (FIR) detectors has been successfully demonstrated using forward biased Si p-i-n diodes at 4.2 K. The basic structure consists of a heavily doped IR absorber layer and an intrinsic (or lightly doped) layer. An interfacial workfunction between these regions defines the long-wavelength cutoff (λc) of the detector. Three types of detectors are distinguished according to the emitter layer doping concentration level. Our model shows that high performance Si FIR detectors (≳40 μm) can be realized using the type-II structures with a tailorable λc, in which the absorber/emitter layer is doped to a level somewhat above the metal-insulator transition value. Analytic expressions are used to obtain the workfunction versus doping concentration, and to describe the carrier photoemission processes. The photoexcitation due to free-carrier absorption, emission to the interfacial barrier, hot-carrier transport, and barrier collection due to the image force effect, are considered in calculating the spectral response and quantum efficiency as functions of device parameters for Si n+-i structures, leading to a detailed photoresponse analysis of type-II detectors. These results are useful for the design and optimization of type-II detectors.1e:T495,Photoelectrical properties of nonuniform semiconductor under IR laser radiation has been investigated theoretically and experimentally. It is shown that photoemission of hot carriers across the potential barrier and the crystal lattice heating are dominant mechanisms of the photovoltage formation in p-n and l-h junction when laser photon energy less than the semiconductor energy gap. Influence of aluminum arsenide model fraction in GaAs/Al_xGa_1-xAs p-n heterojunction on CO₂ laser radiation detection has been studied. It has been established that the photoresponse originating from the free carrier heating depends on the energy band discontinuities in heterojunction. GaAs/Al_xGa_z-xAs heterojunction with x <EQ 0.2 is found to be more suitable for IR detection compared to GaAs homojunction. In metal- semiconductor Schottky contact photoresponse demonstrates strongly nonlinear dependence on excitation intensity when photon energy is less than Schottky barrier height. We suppose that in this case the photosignal is caused by the multiphoton and multi step electron photoemission across the Schottky barrier.

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