The Shape Of 0.6μm Contact's Effect On ALSICU Filling In Process Step Coverage

The paper focuses on the relationship of the contact shape and metal filling effect (PVD process) basing on the 0.6μm, aspect ratio>1contact in CMOS process by Si-substrate and work out the best contact shape by metal filling optimization. In the process of setting up the isotropic and anisotropic etch recipes, study on etching parameters corresponding to the contact profile and set up the wine-shaped contact baseline profile of 1:1 isotropic to anisotropic proportion. To solve the problem of severe low step coverage caused by the sharp-angled joint of isotropic and anisotropic portion, optimize the contact shape by three experiments: lower the height of sharp angles'position, making the sharp angles obtuse, sharp angles filleting. In conclusion, by step coverage under SEM and contact resistance, find the best method of physical bombing filleting on the baseline contact shape.