V. V. Popov - Ph.D. (Eng.), General Director, JSC «Svetlana», St.-Peterburg

The most important problem of semi-insulating silicon carbide wafer manufacturing is the control of electrical resistivity more than 105 Ohm-cm. This is a challenging task from the point of view of measurement technique. It is necessary to choose the measurement method which allows performing effective control of the resistivity in the process of manufacturing. The well-known methods of resistivity control between two ohmic contacts are unusable for the wafers with high electrical resistivity, because Schottky barrier occurs in this case. As a result, upper-range value is limited. Moreover, after such measurements the wafer becomes unmerchantable. In this article, the method of resistivity measurement has been described. It is based on the contactless measuring of time resorption of induced charge. The advantage of this method is that it doesn't damage the wafer and allows resistivity mapping of the wafer. The received data allowed the optimization of all the preparation processes in semi-insulating SiC wafers manufacturing.