MOCVD를 이용한 BiSbTe3 박막성장 및 열전소자 제작

Abstract

Bismuth-antimony-telluride based thermoelectric thin film materials were prepared by metal organic vapor phase deposition using trimethylbismuth, triethylantimony and diisopropyltelluride as metal organic sources. A planar type thermoelectric device has been fabricated using p-type Bi0.4Sb1.6Te3 and n-type Bi2Te3 thin films. Firstly, the p-type thermoelectric element was patterned after growth of 5 ㎛ thickness of Bi0.4Sb1.6Te3 layer. Again n-type Bi2Te3 film was grown onto the patterned p-type thermoelectric film and n-type strips are formed by using selective chemical etchant for Bi2Te3. The top electrical connector was formed by thermally deposited metal film. The generator consists of 20 pairs of p- and n-type legs. We demonstrate complex structures of different conduction types of thermoelectric element on same substrate by two separate runs of MOCVD with etch-stop layer and selective etchant for n-type thermoelectric material. Device performance was evaluated on a number of thermoelectric devices. To demonstrate power generation, one side of the device was heated by heating block and the voltage output was measured. The highest estimated power of 1.3 ㎛ is obtained at the temperature difference of 45 K.