A study of reflective second harmonic generation on coherent Zn/ZnO thin film and dots grown by magnetic RF sputtering

Abstract

The thin film materials have widely application in technology industry The quality of thin film will be influenced at the early stage of thin film growth especially for coherent growth dot or film Therefore to understand the dot or thin film growth at the earlier nucleation stage is important issue in the film growth science Most rf sputtering deposition the growth is self-texture growth which leave the constrain by substrate In this work strategic rf sputtering method was applied to grow coherent Zn dot/film on Si(111) in order to discuss the strain between dot/film and substrate We use rf sputtering to growth coherent dot/film with negative bias and hydrogen flux in rf sputtering however it is so critical to grow well dot on Si(111) since some tiny parameters will influence the dot formation Reflective second harmonic generation (RSHG) is developed to non-destructively analyze coherent Zn dot/film growth by the non-cancelled net symmetrical dipole contribution By comparing with synchrotron XRD experiments this methodology is justified to be a powerful method which can be extended to examine growth evolution Two series studies on coherent Zn dot/film were discussed in this work One is coherent ZnO film at lower substrate temperature We observed the relaxation process after long-time by inspecting RSHG and synchrotron XRD Another is coherent Zn/ZnO dots at high substrate temperature We observed the interaction between dots and substrate during annealing process by inspecting RSHG and synchrotron XRD The relaxation phenomena can be confirmed by anisotropic RSHG decrease and the peak shift of Zn-Si mixture Above works not only present us a effective tools to realize the strain science of coherent dot/film but also give a strain mechanism in dot/ultra-thin film system which is helpful to realize the knowledge of earlier nucleation stage

Date of Award	2015 Jul 24
Original language	English
Supervisor	Kuang-Yao Lo (Supervisor)