By Melbourne Centre for Nanofabrication
The process Furnace systems are used to treat materials at high temperatures to change their properties through diffusion, annealing and chemical vapour deposition. The instruments MCN has two furnace systems - the Expertech CTR-150 and the SVCS four-stack horizontal furnace. The Expertech furnace system is used to create layers of silicon dioxide on a silicon substrate. This can be achieved through wet or dry oxidation. The furnace can operate up to 1100 o C and can perform dry oxidation (O 2 is oxidant) and wet oxidation (steam is oxidant). For wet oxidation, water vapour is generated using a torch which burns O 2 and H 2. The system also has a TLC bubbler (trans-1,2-dichloroethylene); TLC is a non-ozone depleting source of chlorine for scavenging mobile metal ion contaminants that impair gate oxide integrity. This also increases the oxidation process growth rate by a few percent. The Expertech system can accept 4 inch wafers (3 and 6 inch wafers on approval by the process engineer). The SVCS four-stack horizontal furnace system provides access to high temperature processing of silicon and other substrates, with small batch processing options. The four processing tubes cater for atmospheric pressure diffusion, atmospheric pressure annealing and the low-pressure chemical vapour deposition of low strain and stoichiometric silicon nitride. The tool has a HEPA controlled loading station.
