以Al2O3单晶和具有三明治结构的Al2O3单晶-Bi2O3-Al2O3单晶试样为研究对象,测量了在室温到750℃之间升温过程和降温过程中这两种试样的热激发电流,仅在三明治结构试样中检测到了热激发电流.随测量过程中升温速率的增大,降温过程中的热激发电流逐渐减小.认为热激发电流是由缺陷离子的扩散所引起,通过扩散活化能的计算发现有两种缺陷参与了热激发电流的形成.
Thermal stimulated current in Al2O3single crystal and sandwiched Al2O3 single crystal-Bi2O3-Al2O3 single crystal samples was measured during the heating, soaking and cooling processes. It was found that the thermal stimulated current can be detected in sandwiched samples, while no current was observed in the Al2O3 single crystal sample. With the increase of heating rate, the thermal stimulated current measured during cooling decreases, which implies that the thermal stimulated current is induced by defect ions. The calculation of active energy shows that there are two kinds of defect ions involved in producing the thermal stimulated current.