Kinetics of Vacancy Doping in SrTiO3 Studied by in situ Electrical Resistivity

The kinetics of annealing to transform stoichiometric SrTiO3 insulator into a vacancy-doped semiconductor-superconductor was revisited by in situ electrical resistivity measurements. SrTiO3 single crystals were grown by Floating Zone Method. Using a homemade apparatus several electrical resistivity as a function of time were measured at different temperatures, which allows one to study the creation of vacancies during annealing under vacuum. The activation energy for the oxygen vacancies formation/charge doping in SrTiO3 was estimated as 1.4±0.3 eV using solid-state kinetics approach.

本研究通过原位电阻率测量，重新探究了将化学计量比钛酸锶（SrTiO3）绝缘体转化为空位掺杂半导体超导体的退火动力学过程。实验采用浮动区法（Floating Zone Method）制备钛酸锶单晶，借助自制实验装置在不同温度下开展多组电阻率随时间变化的测量，借此可研究真空退火过程中空位的产生机制。通过固态动力学方法，本研究估算出钛酸锶中氧空位形成与电荷掺杂对应的活化能为1.4±0.3 eV。