Measurement of mobility in power trench FET technology using the conductance and transconductance methods

Single cell vertical 20 V p-channel and 30 V n-channel power trench FET devices were measured to extract the channel mobility using the conductance and transconductance methods. Using the conductance method, mobility in the p-channel and n-channel devices was found to be approximately 90 cm/sup 2//V/spl middot/sec and 150 cm/sup 2//V/spl middot/sec respectively. These results are comparable to those found by the transconductance method, indicating that the normal (to channel) field effects on the devices are not considerable for the gate voltage range over which the measurements were conducted.