Patrick R. Varekamp

Nucleation of chemical vapor deposited silicon nitride on silicon dioxide

We have studied the early stages of silicon nitride chemical vapor deposition (CVD) on silicon dioxide using medium energy ion scattering. The growth mode consists of island nucleation followed by coalescence. Similar behavior is observed for films grown using different precursors and reactor environments, indicating that the growth mode is caused by the fundamental nonwetting nature of the nitride/oxide interface under the conditions used for CVD.

Thickness measurement of ultra-thin gate dielectrics under inversion condition

Accurate measurement of inversion thickness is essential in ULSI technology for development and control of ultra-thin gate dielectric processes. However, the accuracy of the measurement can be severely affected by the high gate leakage current and series resistance. This paper presents a methodology to reduce the measurement error by optimizing the ac modulation frequency and test device structures.