Plasma processing method, plasma etching method and manufacturing method of solid-state image sensor

摘要

A method of plasma processing is offered to suppress generation of interface states, specifically to suppress increase in the dark current of a solid-state image sensor by reducing the interface states. An interlayer insulation film made of silicon nitride film is formed over a silicon substrate by plasma CVD, and a photoresist layer is selectively formed on the interlayer insulation film. Subsequent heating process makes a profile of the photoresist layer round. Next, the interlayer insulation film is plasma-etched using the photoresist layer as a mask and a fluorocarbon gas as an etching gas to form micro lenses. Pulse-time-modulated plasma method in which RF power is supplied intermittently is used to suppress increase in the interface states at silicon-silicon dioxide interface due to an influence of UV light generated in the plasma etching.