Collinear acousto-optical interaction in proton-exchanged lithium niobate, and Submicron silicon-on-insulator metal-oxide-semiconductor field-effect-transistors

In part I of this dissertation work, acousto-optical (AO) devices based on collinear AO interaction have been realized on proton-exchange lithium niobate (PE:LiNbO3) waveguides. The significant increase of the extraordinary refractive index in the waveguide due to proton-exchange has made a sufficiently high guided-mode to leaky-mode conversion possible. Experimental results of mode-conversion of as high as 90% efficiency for various cut LiNbO 3 are presented. With such achievement in mode-conversion, potential applications in RF signal processing and optical scanning can be conceived.;In part II of this dissertation work, reliability issues in silicon-on-insulator (SOS) metal-oxide-semiconductor field-effect-transistors (MOSFET) have been extensively investigated. New understandings on slow hole-trapping, hot-carrier effect, and radiation effect in submicron SOS MOSFET are important for the recent developments in commercial satellite communications area where space radiation-hardening devices are required. Slow hole-trapping has always been a concern in P-channel MOSFET reliability. This work shows that N-channel MOSFET fabricated with mesa structure or with shallow trench technology may exhibit slow hole-trapping degradation. The hot-carrier and radiation effects investigation shows that gate oxide integrity in SOS MOSFET are capable of handling radiative environment.