Surface Treatment of Si Using Hydrogen-Plasma to Improve Optoelectronic Property of ZnO on (111)Si

Abstract

A new chemically generated plasma source is reported. The presence of gaseous Rb + or K + ions with thermally dissociated hydrogen formed a low applied temperature, extremely low voltage plasma called a resonant transfer or rt-plasma having strong vacuum ultraviolet emission. We propose an energetic catalytic reaction involving a resonant energy transfer between hydrogen atoms and Rb + or 2K + since Rb + to Rb 2+ , 2K + to K + K 2+ , and K to K 3+ each provide a reaction with a net enthalpy equal to the potential energy of atomic hydrogen. Remarkably, a stationary inverted Lyman population was observed; thus, these catalytic reactions may pump a cw HI laser as predicted by a collisional radiative model used to determine that the observed overpopulation was above threshold.

ZnO Heteroepitaxy on Sapphire Using a Novel Buffer Layer of Titanium Oxide: Crystallographic Behavior

“…have been developed to reduce the native defects. Plasmaassisted epitaxy (PAE) using oxygen plasma excited by radio-frequency (rf) power is also useful to achieve ZnOepitaxial growth at low temperatures supplying reactive oxygen as demonstrated for undoped-ZnO growth at 400˚C on c-sapphire [4,5] and Si [6]. In addition, acceptor-doping with sufficient dopant preventing the self-compensation should be required to fabricate p-type ZnO and the pn-junction.…”