Contactless Mobility Measurements of Inversion Charge Carriers on Silicon Substrates with SiO2 and HfO2 Gate Dielectrics

A method is described to determine the mobility of inversion charge carriers on Si substrates with SiO2 and HfO2 gate dielectrics. It is a completely contactless method combining corona charge and charge spreading metrology. [Patent Application Nos. EP 07118673 and U.S. 60940594.] It is shown that from such measurements mobility of inversion charge carriers can be calculated as a function of the effective electric field. The resulting mobility curves are comparable to those found in transistors.