Fabracation And Charaterization Of Nanostructured Thin Films On Porous Silicon Substrates

As the size of particles comes into nanometers, many new characteristics of the nano-sized particles will come out according to the nano-effects such as Small size effect, Surface and interface effect, quantum size effect, and the quantum confinement effect. These effects make the nano materials an expansive application potential in Photonics, Electronics, Magnetics and Bio-chemistry and et al. and also will promote the basic research to a deep development.In this Master degree thesis, fabrication of Nano-structured Porous Silicon films and Si Nano-crystalline(SiNC) films by electro-chemical method is discussed; its applications in the Sol-Gel process of Nano-crystalline Znic Oxide and Hydroxyapatite thin films are studied. Furthermore, fabrication and characterization of ZnO nano-structure obtained by thermal evaporation are studied experimentally. The mainly works and significant results are listed as following:1) The parameters of forming P-type Porous Silicon, Nano-structured Porous Silicon film and N-type Porous Silicon films by electro-chemical method are studied systematically.2) Selectively formation of porous silicon array using highly resistive silicon layer as masking materials and boron ion implantation are obtained. The application of porous silicon in DNA-chip is also studied.3) HAP has been successfully prepared by sol-gel method. HAP(20 μ m) was successfully coated on PS substrate. It was found that rapid thermal annealing (RTA) process is able to enhance crystallinity of HAP. And 850-950 °C is the best thermal treatment temperature. HAP on Silicon will benefit implantation of sensors and IC in human bodies so as to reduce and even entirely avoid biological rejection.4) Sol-Gel process of Nano-crystalline Znic Oxide thin films on nano structured silicon substrates are studied. ZnO nanostructures are also successfully synthesized by a novel thermal evaporation method. The obtained ZnO samples were characterized by XRD and SEM. The mechanics of ZnO growth by evaporation is discussed. The effect of the annealing temperature on the crystallization of ZnO in the sol-gel process is disscused at the same time and the optimal annealing temperature are measured.