RECOVERY OF SI SURFACES SUBJECTED TO REACTIVE ION ETCHING USING RAPID THERMAL ANNEALING

In a recent report, we demonstrated that rapid thermal annealing (RTA) can be successfully used to recover the surface properties of silicon exposed to reactive ion etching (RIE) in a case where there was no substantial residue (non-silicon) layer produced by the RIE. The RIE process, for which RTA was successful, was CCl//4 blanket etching of bare Si wafers. In that report we suggested that RTA could be successfully employed for the recovery of Si surfaces exposed to other RIE processes, if residue layers were removed prior to rapid thermal annealing. In this study we substantiate that assertion for the case of silicon exposed to CClF//3/H//2 RIE. It is pointed out that the complete evolution of Au/Si contact (1 mm, 1000 Angstrom thick Au dots) electrical behavior for three various processing steps is presented. Shown are the I-V data for a dot to a control surface (curve a), a dot to an RIE-exposed surface (curve b), a dot to an RTA/0//2 ashed/RIE-exposed surface, and a dot to an HF etched/RTA/0//2 ashed/RIE-exposed surface.