Development of CMP Conditioner for Sub-50 nm Technology Nodes

Abstract

Several key conditioner design parameters including diamond size, shape, and concentration were selected and optimized to tune wafer removal rate and pad cut rate for various types of CMP pads. Among various diamond types, two types of diamonds were selected for conditioner applications and numerous conditioners were manufactured to generate pad surface roughness on a regular polyurethane porous pad, hard porous pad, and hard solid pad. Furthermore pad cut rate stability curves and wafer removal rate were generated to correlate conditioner design with pad surface texture and wafer removal rate and defects. Experimental results revealed the effect of conditioner design on pad surface roughness was significant and wafer removal rate varied significantly depending on a specific set of conditioner and pad.