Formation of SCF + , SCF 2 + , and CS 2 + ions during gas modulation cycles associated with interference between alternating C 4 F 8 and SF 6 in Ar plasma
Abstract
Abstract Gas modulation cycle processes for high aspect ratio (HAR) Si etching alternate C 4 F 8 and SF 6 introduction in Ar plasma. Using time-resolved quadrupole mass spectrometry to analyze transient behaviors during these cycles, where gas mixing occurs, we observed the temporal evolution of carbon–sulfur ions such as SCF + , CS 2 + , and SCF 2 + generated. These ions emerge through mutual interference between gas introduction steps, mediated by surface deposition layers and gas-phase reactions. Elucidating the formation mechanisms of these carbon–sulfur ions provide critical insights into phase-specific species composition and its impact on controlling gas modulation cycles, ultimately influencing etch profile control for HAR structures.
Fields of Study & Subjects
Plasma Diagnostics and Applications
Copper Interconnects and Reliability
Silicon and Solar Cell Technologies
Publication details
- Journal / source
- Japanese Journal of Applied Physics
- Publisher
- IOP Publishing
- Volume
- 65
- Issue
- 3
- Pages
- 030904–030904
- Publication date
- 21 January 2026