CHEMICAL PRE-TREATMENT OF SUBSTRATE FOR GROWING HIGH QUALITY THIN FILMS, AND FORMATION OF THERMOELECTRIC THIN FILMS USING THE SAME

摘要

A chemical treating method of substrate and thin film type thermoelectric material using the same are provided, in which crystal growth easily occurs in the growth of different kind of thin film at the top of the substrate. Organic compound remaining in the sapphire substrate surface is removed by using acetone, methanol, and distilled water. The substrate is put into the mixture of the sulfuric acid(H2SO4) and the phosphoric acid(H3PO4) of 3:1 ratio. The substrate is heated at 160deg.C for 10 minutes. The surface of sapphire board is etched. The sapphire substrate prepared through the process is dipped into the potassium hydroxide aqueous solution of 0.1 % concentration for 20 minutes and chemically treated. Bismuth-telluride(Bi2Te3) thin film grows in the reaction tube made of the quartz tube under the atmosphere pressure for 10 seconds using metal-organic chemical vapor deposition.