Ultraviolet photodetector on the basis of heterojunction with textured interface

Characterization of nanoscaled films on flat and grating substrates as some elements of plasmonics

“…It is a system of approximately parallel grooves with the period value which increases with the etching duration. As was shown in our work [9], a real micro-(or nano-) relief of the quasi-grating type is composed of a random distribution of certain-type gratings, i.e. it is intermediate between the periodic and perfectly random ones.…”

“…The former are a result of the holographic etching of the GaAs substrate and has DG (ruled) microstructure. For the latter, images of the same surface on the nanometer scale reveal a morphology of the quasi-grating type resulted from the anisotropic etching of the GaAs (100) substrate [9]. It is a system of approximately parallel grooves with the period value which increases with the etching duration.…”

Distinct UV–Visible Responsivity Enhancement of GaAs Photodetectors via Monolithic Integration of Antireflective Nanopillar Structure and UV Absorbing IGZO Layer

“…[ 22 ] The surface recombination is expected to be more severe in UV range for antireflective structures due to potential formation of more surface states as traps and recombination centers which are introduced by larger surface areas and fabrication methods such as etching. [ 12,23 ] On the other hand, a layer integration with UV absorbing materials in GaAs has been studied as an alternative way to enhance the responsivity of GaAs photodetectors. For example, Xu et al.…”

“…The former issue can be effectively ameliorated by employing various antireflection schemes. Among them, surface texturing such as textured GaAs, [12,13] GaAs nanocones [14,15] and porous GaAs [16][17][18][19] has shown a facile and effective way to achieve a broadband antireflection, compared with a multilayered antireflection coating which requires a precise control of refractive index and thickness of individual layer. [20] Although some of these works on surface texturing demonstrated low UV-visible reflection below 5%, none of them have systematically studied an implication of the textured antireflection layer in GaAs photodetectors and their performance enhancement in a broadband UV-visible range.…”

“…[22] The surface recombination is expected to be more severe in UV range for antireflective structures due to potential formation of more surface states as traps and recombination centers which are introduced by larger surface areas and fabrication methods such as etching. [12,23] On the other hand, Broadband ultraviolet-visible photodetection has been attracting growing research interests in fields of environment, energy, and imaging. Considering the suitable bandgap and high absorption coefficient, GaAs is one of the best candidates for ultraviolet-visible photodetection.…”