New technique for the thermal resistance measurement of power field effecttransistors using cathodoluminescence

A new approach for measuring the thermal resistance of power field-effect t ransistors (FETs) with extremely high spatial resolution below 40 nm has be en demonstrated using cathodoluminescence generated by a low-energy electro n beam. The energy shift of the fundamental bandgap caused by the current h eating in the channel region is spatially probed, and is converted to the c hannel temperature using the temperature dependence of the material bandgap . The obtained thermal resistances of the GaAs metal semiconductor field ef fect transistor (MESFET) and the GaN MESFET are compared with those measure d by the conventional electrical technique.