MOS capacitors and NMOS transistors were fabricated with various gate oxides and inter- level dielectrics (ILDs) in order to study the effects of plasma induced charging during the post-metal plasma deposition of an insulating oxide layer. The gate oxides investigated include thermal SiO 2, a low temperature oxide (LTO) deposited by low pressure chemical vapor deposition (LPCVD) using silane and oxygen, and an oxide deposited by plasma enhanced chemical vapor deposition (PECVD) using tetra-ethylortho- silicate (TEOS) as a precursor. A standard-recipe TEOS-based ILD was studied, as well as an alternative recipe that utilized decreased power. Additional wafers were fabricated with an LTO ILD to serve as a control group in order to isolate the influence of the ILD deposition on the respective gate dielectric. By studying C-V and I-V characteristics, both interfacial degradation as well as bulk charging was demonstrated as a result of the PECVD ILD deposition. The investigation demonstrated clear differences in plasma- induced charge effects on the various gate dielectrics. A correlation between the ILD deposition power and the resulting charge influence was established. In addition, post-plasma annealing experiments were done to study the thermal stability of induced charge.

Library of Congress Subject Headings

Metal oxide semiconductors--Research; Gate array circuits; Semiconductors--Defects; Dielectric devices; Plasma radiation

Publication Date


Document Type


Department, Program, or Center

Center for Materials Science and Engineering


Hirschman, Karl

Advisor/Committee Member

Jackson, Michael

Advisor/Committee Member

Langner, Andreas


Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works. Physical copy available through RIT's The Wallace Library at: TK7871.99.M44 M85 2006


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