Two-dimensional dopant Profiling on Operating MOSFET by Scanning Capacitance Microscopy

Abstract

We introduce scanning capacitance force microscopy (SCFM), a newly developed dopant profiling method, and a 3-dimensional wiring procedure enabling evaluation of dopant profile under metal-oxide-semiconductor field-effect-transistor (MOSFET) operation. The principle of the SCFM is based on measurement of an electrostatic force (ESF) that is induced by bias voltage of angular frequency ω between a tip and a sample. The focused ion beam (FIB) technique was employed to evaluate dopant profile for the cross-section of MOSFET devices under the device operation. Local etching, deposition, and formation of small wiring for the specified MOSFET were successively carried out with the FIB, and the variation of dopant profiling was clearly shown with applying voltage to the MOSFET. These techniques are expected to be utilized for the failure analysis and the development of next-generation devices.