High-k MOSFET performance degradation by plasma process-induced charging damage - Impacts on device parameter variation

• Main Authors: Eriguchi, K., Kamei, M., Takao, Y., Ono, K.
• Format: Conference Proceeding
• Language: eng ; jpn
• Subjects: Antennas; High K dielectric materials; Integrated circuit interconnections; Logic gates; Plasmas; Stress; Threshold voltage
• ISSN: 1930-8841; 2374-8036
• DOI: 10.1109/IIRW.2012.6468925

We discuss plasma charging damage (PCD) to high-k gate dielectrics, in particular, the threshold voltage shift (ΔV th ) in metal-oxide-semiconductor field-effect transistors (MOSFETs). The PCD induced by the antenna effect is focused on, and ΔV th and its variation are estimated for MOSFETs treated by various plasma processes. The direction of threshold voltage shift in damaged high-k MOSFETs was found to depend on the amount of damage, i.e., the polarity itself results in "negative" or "positive" as the charging damage varies. We demonstrate a model prediction based on both the power-law dependence of ΔV th on the antenna ratio r (= exposed metal interconnect area/gate area) and the r distribution deduced from an interconnect-length distribution function (ILDF) in a large-scale integrated (LSI) circuit. Then, we simulate the variation in ΔV th [σ(ΔV th )]. PCD to high-k dielectrics may lead to a considerable contribution to MOSFET-parameter fluctuations.