Oxygen vacancy, as a kind of self-doping strategy, has been considered by numerous researchers. Several papers have been published about introducing oxygen vacancies in the semiconductors, which give a viewpoint that the concentration of oxygen vacancies may influence the performance. But few of them focus on how to control the concentration of oxygen vacancies, and how to achieve the goal without using additional equipment (such as sealed tube furnace) for too long time (20 min-4 h without considering the time for rising temperature and cooling). In this paper, oxygen vacancies were introduce...