By Melbourne Centre for Nanofabrication
Spectroscopic ellipsometry is an optical characterisation technique which provides unequalled sensitivity and a non-destructive, contact-less method for thin film measurements. It uses polarised light which is reflected off a sample, undergoing a change in polarisation as it interacts with the sample surface. The changes that occur provide data which enables users to characterise certain properties. Multiple light wavelengths and variable angles are used to provide a comprehensive data set. Ellipsometry is primarily used to characterise film thickness as well as composition such as roughness, crystalline nature, electrical conductivity and doping concentration. It can be used to measure a wide variety of films. MCN’s ellipsometry instrument is the J.A Woollam M-2000DI which is able to collect over 500 wavelengths simultaneously. It is able to measure films between 2nm and 3µm thick.
