Feasibility Study of Traveling Wave Devices Using Compound Semiconductor Superlattice Structures

点击翻译按钮获取中文摘要

The purpose of the research is to investigate the feasibility of new-type of traveling wave devices using compound semiconductor superlattice structures. The main results are the following:[1] Theoretical analysis of the traveling wave interactions was made on the superlattice structures with finite dimensions of semiconductor plasma. An ideal non-dispersive slow wave structure and an interdigital slow wave structure were studied with the latter involving a complicated self-consistent computer field analysis over space harmonic field components present in the semiconductor plasma of finite dimensions. The analysis has clearly shown the feasibility of microwave and millimeter-wave traveling wave devices. Importance of Debye screening length of plasma with respect to the active layer thickness was demonstrated and the advantage of superlattice structure was indicated.[2] Dielectric spacers with a high breakdown field strength and minimal deposition damage to Semiconductor active layers is essential for coupling between slow-wave and semiconductor carrier wave. For this purpose, a room temperature deposition process of PCVD silicon nitride was successfully developed, using 50Hz plasma.[3] Three kinds of interdigital traveling wave devices having n-GaAs MOVPE single layer, AlGaAs-GaAs MBE hetero structure layers and n-InP single layer as the active layer, respectively, were fabricated. Two-terminal admittance measurements clearly indicated presence of traveling wave interactions at microwave frequencies in all types of the experimental devices. Furthermore, the measured behavior of two-terminal admittance of the InP device showed an excellent agreement with the result of the detailed computer simulation, establishing the design philosophy for devices with the maximum interaction gain.