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The unique degradation behavior of a tunneling field-effect transistor (TFET) under hot-carrier injection (HCI) stress has been previously investigated. However, while the source side (p+/p junction) of degradation (due to HCI stress) has been extensively studied, the drain side (p/n+ junction) has not been investigated yet. Our study revealed that both bulk oxide and interfacial layer degradation occurred at the drain side, while an interfacial layer degradation was dominant at the source side at 300 K. This evidences a unique degradation mechanism of the tunneling FET.

GaAs/GaInAs multiple-quantum-well (MQW) shells having different GaInAs shell width formed on the surface of self-catalyzed GaAs core nanowires (NWs) are grown on (100) Si substrate using molecular beam epitaxy. The photoluminescence emission from GaAs/GaInAs MQW shells and the carrier lifetime could be varied by changing the width of GaInAs shell. Time-resolved photoluminescence measurements showed that the carrier lifetime had a fast and slow decay owing to the mixing of wurtzite and zinc-blende structures of the NWs. Furthermore, strain relaxation caused the carrier lifetime to decrease beyond a certain thickness of GaInAs quantum well shells.

In general, to realize full color, inorganic light-emitting diodes (LEDs) are diced from respective red-green-blue (RGB) wafers consisting of inorganic crystalline semiconductors. Although this conventional method can realize full color, it is limited when applied to microdisplays requiring high resolution. Designing a structure emitting various colors by integrating both AlGaInP-based and InGaN-based LEDs onto one substrate could be a solution to achieve full color with high resolution. Herein, we introduce adhesive bonding and a chemical wet etching process to monolithically integrate two materials with different bandgap energies for green and red light emission. We successfully transferred AlGaInP-based red LED film onto InGaN-based green LEDs without any cracks or void areas and then separated the green and red subpixel LEDs in a lateral direction; the dual color LEDs integrated by the bonding technique were tunable from the green to red color regions (530–630 nm) as intended. In addition, we studied vertically stacked subpixel LEDs by deeply analyzing their light absorption and the interaction between the top and bottom pixels to achieve ultra-high resolution.

High-performance GaAs tunnel diodes (TDs) are fabricated by using Si delta-doping technique. The GaAs TDs exhibited a high peak tunnel-current density of 2,735 A/cm2 and low specific resistivity of 1.46 × 10−4 Ωcm2. However, the performance of the GaAs TDs deteriorated once the amount of Si delta doping exceeded a certain limit, which has been rarely reported elsewhere. Detailed analyses and numerical simulations of GaAs TDs with various amounts of Si delta doping prove that Si amphoteric behavior governs the performance limit. GaAs TDs with precisely controlled Si delta doping are suitable for cutting-edge tandem solar cell applications.

We report changes at the interface between Ga-rich/In-rich GaInP vertical slabs in laterally composition modulated (LCM) GaInP as a function of the V/III ratio. The photoluminescence exhibits satellite peaks, indicating that the parasitic potential between the GaInP vertical slabs disappears as the V/III ratio decreases. However, a high V/III ratio leads to an abrupt interface, increasing the parasitic potential because of the phosphorus-amount-dependent diffusion of group-III atoms during growth. These results suggest that the V/III ratio is an important parameter that must be wisely chosen in designing optoelectronic devices incorporating LCM structure.

Double-hetero structure lateral composition modulated (LCM) GaInP and sandwiched LCM GaInP having the same active layer thickness were grown and their optical properties were compared. Sandwiched LCM GaInP showed robust optical properties due to periodic potential nature of the LCM structure, and the periodicity was undistorted even for thickness far beyond the critical layer thickness. A thick LCM GaInP structure with undistorted potential that could preserve the properties of native LCM structure was possible by stacking thin LCM GaInP structures interspaced with strain compensating GaInP layers. The sandwiched structure could be beneficial in realizing the LCM structure embedded high efficiency solar cells.