A contrast between rule-based and model-based dummy metal fill in ASIC design

Chemical-mechanical polishing (CMP) is an essential process in deep-submicrometer LSI manufacturing to achieve Chip´s planarization. It includes two processes: back-end-of-line (BEOL) and front-end-of-line (FEOL). We focus the problem on BEOL in 65nm Copper Process. Through model-based dummy metal fill is becoming a tendency recently, we proved that rule-based dummy fill is appropriate still. We apply the improved rule-based dummy fill into a middle scale design. We investigated the oxide and metal thickness, the capacitance variation and variation of layout data size. The result show that improved rule-based dummy fill is still effective in 65nm process, and model-based dummy fill is not better than the rule-based obviously.