| AVS 63rd International Symposium & Exhibition | |
| Plasma Science and Technology | Thursday Sessions |
| Session PS2-ThM |
| Session: | Plasma Processing of Challenging Materials |
| Presenter: | Jason Peck, University of Illinois at Urbana-Champaign |
| Authors: | J.A. Peck, University of Illinois at Urbana-Champaign G.A. Panici, University of Illinois at Urbana-Champaign I.A. Shchelkanov, University of Illinois at Urbana-Champaign S. Hammouti, University of Illinois at Urbana-Champaign D.N. Ruzic, University of Illinois at Urbana-Champaign |
| Correspondent: | Click to Email |
Dry etch assisted by laser (DEAL) of silicon and copper via Ar/C4F8/O2, Ar/SF6, and Ar/CCl4 capacitively-coupled plasma was studied, with goals including form control for sub-22 nm features and uniformity for 450 mm wafer processes. The first phase of the study consisted of wavelength (1064, 532, 266 nm) investigation, variation of gas chemistry, and laser intensity ramping. Multiple lasers were employed to vary repetition rate, from CW, 100 Hz, or 100 kHz, as well as varied pulse width, 350 fs to 7 ns, to understand instantaneous laser power against gas dynamics timescales.
The second phase of the study explored multiple material candidates, focusing particularly on metal etch. The etch rate enhancements were determined in the case of Si and Cu etch. Etch activation in zero-etch recipes was achieved upon introduction of 532/266 nm wavelength in the case of silicon and 1064 nm in the case of copper. In particular, Cu etch was demonstrated at substrate temperatures (40-70°C) far below the required temperature to produce a volatile etch product. Scalability and the ease of incorporating this technique into industry processes will be discussed.