Spectroscopic charge pumping investigation of the amphoteric nature of Si/SiO2 interface states

The amphoteric nature of Si/SiO2 interface states in submicron sized metal-oxide-silicon-field-effect-transistors is observed using an enhanced spectroscopic charge pumping method. The method’s simplicity and high sensitivity makes it a powerful tool for interrogating the true nature of electrically measured interface states in samples which exhibit extremely low defect densities. The spectroscopic results obtained clearly illustrate a signature “double peak” density of states consistent with amphoteric Pb center data obtained from electron spin resonance measurements. Since the method is a hybrid of the commonly used charge pumping methodology, it should find widespread use in electronic device characterization.