Quasi-phase-matched (QPM) GaP layers up to 300 μm thick have been produced by low-pressure hydride vapor phase epitaxy (LP-HVPE) overgrowth on orientation-patterned GaAs (OPGaAs) templates fabricated using a wafer-fusion bonding technique.
The model consists of two dielectric layers: insulation layer and air-gap layer.
Each layer, referred by index i ((i = 1) insulation layer, 2 air-gap layer), has a uniform absolute permittivity (varepsilon _i), electrical conductivity (sigma _i), and thickness (d_i).
In these structures multilayer cascade elements reduce losses, caused by generation of "hot" carriers and the upper graded band-gap layer improves the conversion of short-wavelength radiation.
A new structure of three cascade solar cells with graded band-gap layer on the base of GaAs AlGaAs heterosystem is designed to decrease the thermal losses, arising as a result of absorption of short-wavelength radiation.
For pillar cavities, partial air-gap layers like in GaAs/air DBR cavities [18] might be incorporated to enhance the refractive index contrast.
The influence of near-surface graded-gap layers on the admittance of MIS structures based on molecular beam epitaxy-grown HgCdTe was studied in detail in [6, 7].
Compared to the previous air-gap DBR cavities [13, 17, 18], in which non-air-gap regions are imperfect features or mechanical supporters, the remaining semiconductor in the partial air-gap layers here takes both the mechanically supporting and optically confining roles so that the present cavity appears completely free standing.
Composite transparent conductive layers (TCLs) were deposited on the GaP window layer of p-side-up thin-film AlGaInP light-emitting diodes (LEDs) in order to enhance their light-extraction efficiency.
We found different optimal growth conditions for GaP buffer layer growth and subsequent deposition of InxGa1−xP layers with graded value of xIn.
