摘要:
A stress relief layer between a single-crystal semiconductor substrate and a deposited silicon nitride layer or pad nitride is formed from thermally produced silicon nitride. The stress relief layer made from thermally produced silicon nitride replaces a silicon dioxide layer or pad oxide which is customary at this location for example in connection with mask layers. After patterning of a mask, which includes a protective layer portion formed from deposited silicon nitride, the material which is provided according to the invention for the stress relief layer reduces the restrictions imposed for subsequent process steps, such as for example wet-etching steps, acting both on the semiconductor substrate or structures in the semiconductor substrate and also on the stress relief layer. The thermal nitriding is advantageously incorporated into a preanneal step for expelling oxygen from the semiconductor substrate, so that the semiconductor substrate is protected from the etching action of the expelled oxygen by the stress relief layer which is formed, there is no need for an additional temporary etching protection layer for the semiconductor substrate and the overall processing is streamlined.
摘要:
During a selective oxidation of gate structures that includes a polycrystalline silicon layer and a tungsten layer, which is known per se, a vapor deposition of tungsten oxide is prevented or at least greatly reduced by a special process. The gate structure is acted on by a hydrogen-containing, nonaqueous inert gas before and, if appropriate, after a treatment step with a hydrogen/water mixture.