The effect of the buffer layer and seed layer of Zn oxide shell/Zn dot on ZnO thin film grown on Si(111)

Abstract

The RF-sputtering was been used to grow high-quality ZnO thin film with Zn quantum dots as seed layer and buffer layer As the problem of the lattice mismatch the deposited thin film usually need a buffer layer between thin film and substrate to reach the requirement of high quality However the thickness of buffer layer was usually over 100nm With the rapid development of semiconductor the effectively method to reduce thickness and grow the high-quality thin film were quite important In this work the process of grown Zn quantum dots was in high vacuum pressure (3×10-6 torr) on Si(111) surface the size and uniformity of Zn dots grown on Si(111) were performed by well controlling growth temperature deposition time power and H2 flow After the growth the Zn quantum dots the different oxidation of Zn quantum dots were be imported then the ZnO film were deposited on Zn quantum dots There are four oxidation condition in the Zn quantum dots oxidation The Zn quantum were be controlled by with and without oxidation different oxidation gas different O3 pressure with UV254nm illuminated different O3 exposed time with UV254nm illuminated Besides Zn quantum dots were not only buffer layer but also seed layer which were enhanced the ZnO quality with better 3m surface symmetry To confirm the quality of ZnO thin film and the influence of ZnO shell/Zn/dots second harmonic generation (SHG) system were been used to observed the crystal structure symmetry The crystal orientation of ZnO thin film and Zn dots were inspected by synchrotron XRD For the results the quality and symmetry of ZnO thin film were be enhanced by mean of uniform Zn quantum dots as seed layer and buffer layer with specific oxidation condition

Date of Award	2020
Original language	English
Supervisor	Kuang-Yao Lo (Supervisor)