Direct wafer bonding technology is able to integrate two smooth wafers and thus can be used in fabricating III–V multijunction solar cells with lattice mismatch. In order to monolithically interconnect between the GaInP/GaAs and InGaAsP/InGaAs subcells, the bonded GaAs/InP heterojunction must be a highly conductive ohmic junction or a tunnel junction. Three types of bonding interfaces were designe...
It is still a great challenge for semiconductor based-devices to obtain a large magnetoresistance (MR) effect under a low magnetic field at room temperature. In this paper, the photoinduced MR effects under different intensities of illumination at room temperature are investigated in a semi-insulating gallium arsenide (SI-GaAs)-based Ag/SI–GaAs/Ag device. The device is subjected to the irradiation...
InAs segments were grown on top of GaAs islands, initially created by droplet epitaxy on silicon substrate. We systematically explored the growth-parameter space for the deposition of InAs, identifying the conditions for the selective growth on GaAs and for purely axial growth. The axial InAs segments were formed with their sidewalls rotated by 30$^{{}^\circ }$ compared to the GaAs base islands un...
This paper proposes a new three-dimensional (3D) photolithography technology for a high-resolution micropatterning process on a fiber substrate. A brief review on the lithography technology of the non-planar surface is also presented. The proposed technology mainly comprises the microfabrication of the 3D exposure module and the spray deposition of thin resist films on the fiber. The 3D exposure m...
Te-doped GaSb single crystals are studied by measuring Hall effect, infrared (IR) transmission and photoluminescence (PL) spectra. It is found that the n-type GaSb with IR transmittance can be obtained as high as 60% by the critical control of the Te-doping concentration and electrical compensation. The concentration of the native acceptor-associated defects is apparently low in the Te-doped GaSb ...
We have improved the efficiency of photoconductive antennas (PCAs) using low-temperature-grown GaAs (LT-GaAs). We found that the physical properties of LT-GaAs photoconductive layers greatly affect the generation and detection characteristics of terahertz (THz) waves. In THz generation, high photoexcited carrier mobility and the presence of a few As clusters in the LT-GaAs are two important factor...