Silicon Damage Mechanism In Oxide Etch

Silicon damage is an important issue in current ULSI fabrication because diode leakage is directly relate to the substrate damage. In most case high silicon etch selectivity is required to reduce the silicon damage in oxide etch. However, very severe silicon damage was observed after the oxide etching. In this paper we will present the proposed silicon damage mechanism for oxide etch and based on the mechanism what we proposed a new process was suggested. Experimental results show that the diode leakage reduce dramatically after change to new process condition.