Sidewall structure and method of fabrication for reducing oxygen diffusion to contact plugs during CW hole reactive ion etch processing

摘要

The present invention provides a sidewall oxygen diffusion barrier and method for fabricating the sidewall oxygen diffusion barrier to reduce the diffusion of oxygen to contact plugs during CW hole reactive ion etch processing of a ferroelectric capacitor of an FeRAM device. In one embodiment the sidewall barrier is formed from a substrate fence, while in another embodiment the sidewall barrier is formed by etching back an oxygen barrier.