A new method to electrically determine effective MOSFET channel width

A new, easy, and accurate electrical measurement method for determining process bias of MOSFET channel width is proposed. This method is based on the linear relationship between the effective width and the channel conductance (or drain current) of a MOSFET operating in the linear region. Constant and sufficiently high gate voltages compared with the threshold voltage of the device are used in the measurement to minimize the error due to the threshold-voltage variation with W in narrow-width devices. The validity of the method is supported by identical results obtained using different gate voltages.