CLEANING OF ANTI-FUSE CONTACT AND ANTI-FUSE

摘要

PURPOSE: To remove uneven breakdown voltage or asymmetry of antifuse polarity and to avoid undue external diffusion of hydrogen while eliminating the need of both sputtering and high temperature annealing in conventional contact cleaning method. CONSTITUTION: Thin reactive metals 22, 24 and 34 are caused to react at a temperature lower than about 450 deg.C and the antifuse contact 30 of metal 20/α-Si32/metal 36 is cleaned by removing the natural interface layer therof. The thin reactive metal of Ti limits reaction and mutual diffusion at the interface of a metal andα-Si during fabrication process involving a temperature cycle lower than 450 deg.C. Reaction and mutual diffusion of Ti andα-Si are also limited. According to the method, leakage current and breakdown voltage of antifuse can be controlled.