Dopant profile extraction and dielectric characterization using scanning capacitance microscopy

Abstract

Scanning capacitance microscopy (SCM) has been recognized as a useful high spatial resolution technique for semiconductor dopant profiling. The SCM measures the difference capacitance (I?C) profile of a metal-oxide-semiconductor (MOS) structure, from which the dopant profile information can be extracted. This project first investigates some of the issues currently affecting the accuracy of SCM dopant profile extraction. These issues include the problems experienced in the SCM experimental setup (e.g. DC bias, AC bias and sweep rate variation) and the physical effects arising from different oxide characteristics (e.g. different oxide quality and contrast reversal effect). In addition, this project also utilizes the SCM for dielectric characterization of silicon dioxide (SiO2), as well as several high dielectric constant (high-k) materials, such as hafnium oxide (HfO2), yttrium dioxide (Y2O3) and aluminum dioxide (Al2O3). The full-width at half-maximum (FWHM) of the SCM a??C characteristics is used as a method to monitor the oxide interfacial quality.