Micro and nanoscale measurement and characterisation accelerate development of new products from initial conceptualisation through to evaluation and testing of prototypes and manufacture of final devices. The Centre of Excellence in Metrology for Micro and Nano Technologies (CEMMNT) provides access to equipment and expertise to accelerate product commercialisation as illustrated by the following examples.
Wafer Crystal Inspection by XRT
The X-ray Topography (XRT) image of a 30 mm diameter silicon carbide wafer reveals dislocations, sub-surface defects and grain boundaries. XRT can be applied for imaging distorted or defective single crystals and identifying sub-surface defects and residual strain in wafers and patterned devices (Copyright QinetiQ).
Figure 1. X-ray Topography maps crystal defects in a silicon carbide wafer
Effects of Surface Treatment on Silicon: XPS Characterisation
X-ray Photoelectron Spectroscopy (XPS) survey spectra from silicon wafers, allowing identification of residual surface contaminants after initial treatment (red plot), and confirming derivatisation after subsequent organosilane reaction (green & blue traces). XPS is an effective tool for obtaining a compositional analysis as well as chemical bonding information from the first few surface atomic layers (up to 5-10 nanometres depth). Varying take-off angle (TOA) allows different surface depths to be sampled within this range (Data Copyright QinetiQ).
Figure 2. X-ray Photoelectron Spectroscopy (XPS) survey spectra from silicon wafers, after pre-treatment (red) and reaction with organosilane (green & blue).