The effects of substrate temperature and oxygen pressure on the crystal strcture and transport properties of Bi2Sr2Co2Oy thermoelectric films deposited by pulsed laser deposition
脉冲激光沉积温度及氧压对Bi2Sr2Co2Oy热电薄膜晶体结构与电输运性能的影响

We fabricate Bi2Sr2Co2Oy films on c-Al2O3 by pulsed laser deposition and investigate the effects of substrate temperature and oxygen pressure on the crystal stucture and the transport properties of the films. The resulting single phase c-axis Bi2Sr2Co2Oy films obtained under the optimal condition have a room temperature resistivity of about 2.9 mΩ/cm and a seebeck coefficient of 110 μupV/K, leading to a larger power factor than that of the single crystal. In addition, a negative magnetroresistance of 40% at 2K and 9T is observed in the films.