ClF/sub 3/ gas compound for particle free contact hole etching

We propose a novel contact hole etching process using gas phase reaction of ClF/sub 3/. Particle free etching can be achieved by suppressing polymer deposition on the chamber wall while maintaining high oxide/silicon selectivity. ClF/sub 3/ can simultaneously etch oxide and clean the chamber wall. The same chamber can be used to remove the damaged silicon layer after contact hole formation and additional plasma apparatus, which has been necessary in conventional etching, is eliminated. This technology ensures high yield and cost-effective contact hole etching.<>