Development of Unexplored Frequency Semiconductor Light Sources ; Deep-UV LEDs and THz-QCLs
平山 秀樹 博士
The development of new-frequency semiconductor light sources, such as deep-ultraviolet (DUV) light-emitting diodes (LEDs) and laser diodes (LDs) and terahertz quantum-cascade lasers (THz-QCLs) is one of the most important subjects, because they are quite useful for variety of applications such as sterilization, water-purifications, medical fields or non-destructive seeing-through examinations, and so on. We are developing unexplored frequency DUV-LEDs and THz-QCLs using wide-bandgap AlGaN and GaAs based semiconductors. We achieved 222-351 nm DUV-LEDs by developing AlGaN/AlN crystal growth techniques. We have also developed THz-QCLs using GaAs and GaN based semiconductors. We achieved high operating temperature for low frequency QCL by introducing a novel quantum structure. We also achieved the first demonstration of GaN based QCLs.
|Fig. 1 Schematic structure and operating spectra of AlN/AlGaN DUV LEDs||Fig. 2 Schematic structure and operating characteristics of GaN/AlGaN THz-QCL|