Production worthy 0.25 /spl mu/m polycide gate etch system

Gate geometry decreases create an increased demand for Tungsten polycide use due to its outstanding thermal stability and low resistivity. Tungsten polycide (W-Si) on polysilicon stacked gate is defined by the process of sequential etch of the two layers. This process requires high etch selectivities between W-Si and polysilicon, and between polysilicon and oxide; good etch uniformity for both layers; and vertical profile without undercut and notching, in addition to the polysilicon-only gate etch. As the industry moves toward mainstream production of smaller and smaller feature sizes the importance of consistent and stable etching results are only matched by the importance of machine reliability. In the Tegal 6510 HRe/sup -/ high density etcher, a demonstration of 0.25 /spl mu/m thin stack silicide technology was performed. Process stability and equipment reliability were evaluated using extensive passive data collection and IRONMAN methodology respectively.