A etch stop layer for use in a silicon oxide dry fluorine etch process is made of silicon nitride with hydrogen incorporated in it either in the form of N--H bonds, O--H bonds, or entrapped free hydrogen. The etch stop layer is made by either increasing the NH.sub.3 flow, decreasing the SiH.sub.4 flow,...http://www.google.es/patents/US6013943?utm_source=gb-gplus-sharePatente US6013943 - Etch stop for use in etching of silicon oxide
