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We have used contactless photoconductance decay measurements to monitor cleaning processes, surface contamination, and surface roughness. Changes in surface chemistry are evidenced by a degradation (increase) in the surface recombination velocity (decrease in measured decay time). We have applied the tool to monitor cleaning effectiveness, surface cleanliness, and roughness during cell processing. Iodine in methanol achieves a superior passivation of Si than H in 48% HE The measured minority carrier lifetime in this solution is higher than in 48% HE We illustrate that I-terminated silicon surfaces are more stable than H-terminated surfaces. We confirm that deionized water is responsible for the roughening of silicon surfaces. We show that NH4F is a superior alternate clean to dilute HF.

The effects of UV radiation curing on the glass structure and fracture properties were examined for a class of nanoporous organosilicate low dielectric constant films. A detailed characterization by nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy showed significant changes in the glass structure with increasing curing time, marked by the removal of terminal organic groups and increased network-forming bonds following the initial removal of porogen material. The higher degree of film connectivity brought about by an increased cure duration is demonstrated to significantly enhance adhesive fracture properties and to moderately improve cohesive fracture resistance. Explanations for the enhanced fracture behavior are considered in terms of the glass structure. The important role of crack path selection during adhesive and cohesive fracture processes is used to rationalize the observed behavior.

A silicon nitride film, Damascene Nitride™, is deposited in a plasma-enhanced chemical vapor deposition ͑PECVD͒ chamber with a conical hole faceplate using silane and ammonia as precursors. Fourier transform infrared analysis indicates that Damascene Nitride is similar to a high-density plasma nitride film. Hydrogen forward scattering spectroscopic analysis shows the film's hydrogen content to be 13%, ϳ6% less than other PECVD nitride films, leading to a 20% improvement in etch selectivity to fluorinated silicate glass. Secondary ion mass spectrometric analysis shows that Cu diffusion is Ͻ250 Å in the nitride; a low leakage current (10 Ϫ12 A) is confirmed through bias temperature stress testing. The higher density of Damascene Nitride leads to higher etch selectivity and better Cu barrier properties, allowing a thinner nitride film to be used. Thinner nitride layers, in addition to the lower dielectric constant ͑͒ of Damascene Nitride, leads to a 5-6% reduction in resistance-capacitance delay when Damascene Nitride is used with low-dielectric materials.

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