【正文】 A、 B: constant。 when t d≈ B t/A A and B can be obtained from ?handbook‘ 14121 ??? tABAdBA422) Deposition (no chemical reaction on surface) Vacuum chambers are needed + thin film deposition Al, Au, Cr 3) Sputtering A momentumexchange process (not heating) Low temperature process We can sputter anything onto substrate theoretically 4)CVD (Chemical Vapor Deposition) (1) ( 300~500176。 C ) 2SiO22 S iOOSi ??222 2HS iOgOH2Si ??? ）（ Si d Where t: time。 C ) Typically CVD films are ~2um thickness in MEMS use. (2) (700176。 C~1200176。 C~900176。 C, 4hr) Wet oxidation: ( 800176。 C) (3) ( 600176。m features ? Diffraction effects are minimized ? Electron beam can detect surface features for very accurate registrar Cons – Swelling occurs when developing negative electron beam resists, limiting resolution – Expensive as pared to light lithography systems – Slower as pared to light lithography systems – Forward scattering in the resist and back scattering in the substrate limit resolution 5. Diffusion and Implantation of Dopants film addition ? PR Spin on ? Thermal oxidation ? Thermal evaporation ? Ebeam evaporation ? Sputtering process ? CVD (LPCVD,PECVD) ? Electroplating