IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Plasma Science Thursday Sessions
       Session PS-ThP

Paper PS-ThP17
N@sub 2@ Addition Effect on Highly Accurate Organic Low-k Etching Process

Thursday, November 1, 2001, 5:30 pm, Room 134/135

Session: Plasma Etching Poster Session
Presenter: T. Hayashi, ULVAC JAPAN Ltd.
Authors: Y. Morikawa, ULVAC JAPAN Ltd.
M. Ozawa, ULVAC JAPAN Ltd.
N. Mizutzni, ULVAC JAPAN Ltd.
T. Hayashi, ULVAC JAPAN Ltd.
T. Uchida, ULVAC JAPAN Ltd.
Correspondent: Click to Email
Etchings for organic low-k materials, FLARE@super TM@ and SiLK@super TM@, had been carried out at a N@sub 2@ dominant mixing ratio in an N@sub 2@ + H@sub 2@ plasma generated by the magnetic neutral loop discharge (NLD) method at low-pressure below 1 Pa.@footnote 1@. We had tried to control micro-trench free profile by using nitrogen-organic surface reactions in a fine pattern etch process. As the result, we were able to successfully control the profiles without micro-trench when the substrate temperature was kept above 0°C, blow 1 pa. Usually, when the N@sub 2@ + H@sub 2@ plasma with H@sub 2@ dominant mixing ratio or only NH@sub 3@ plasma is used, bowing profiles were obtained such a substrate temperature. However, the plasma with the N@sub 2@ dominant mixing ratio was used, bowing did not occur in the temperature range of 0°C to 30°C. Under this condition, the N1s/C1s ratio on the etched surface increased with increase of the temperature. This may be due to an enhancement of nitrogen addition reactions on the surface and thereby the sidewall is passivated. Negative ions in the H@sub 2@+N@sub 2@ plasma were measured by using a quadrupole mass spectrometer. NH@sub 2@@super -@ and CN@super -@ negative ions were observed as main peaks. These species decreased with the pressure. The CN@super -@ ion signal abruptly decreased at the end point. We will also report a finely deep etching process over 1.0 µm without any micro trench and without pillar residues on the etched surfaces. @FootnoteText@@footnote 1@Y. Morikawa et al, Proc.Symp.Dry Process, 263 (2000) @footnote 2@Y. Morikawa et al, J.Vac.Sci.Technol.,A19 (4), Jul/Aug (2000).