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-ThP35
Novel Organic Low-k Dielectric Etching by Using CH@sub 3@NH@sub 2@ / N@sub 2@ Plasma

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

Session: Plasma Etching Poster Session
Presenter: H. Nakagawa, Matsushita Electric Co., Ltd., Japan
Authors: H. Nakagawa, Matsushita Electric Co., Ltd., Japan
Y. Morikawa, ULVAC JAPAN Ltd.
T. Hayashi, ULVAC JAPAN Ltd.
Correspondent: Click to Email
A Novel organic low-k etching has been developed by using a new gas chemistry of CH@sub 3@NH@sub 2@ / N@sub 2@ in a neutral loop discharge (NLD) plasma system. The organic low-k etching produces normal taper profile, no micro-trench, and small hard-mask erosion, which required for fabricating Cu / organic low-k damascene multilevel interconnects. The concept of etching is to introduce C-H passivation film with appropriate thickness on sidewall and bottom of etched patterns, and employing CH@sub 3@NH@sub 2@ / N@sub 2@ has led to the achievement of the required performance. Furthermore, we can control the taper angle of the etched profile by changing a flow ratio of CH@sub 3@NH@sub 2@ / N@sub 2@ and N@sub 2@ in this chemistry. We have already reported that the via hole etching with normal taper profile, no micro-trench and small hard-mask erosion is obtained by using a gas mixture of CH@sub 4@ / N@sub 2@ in neutral loop discharge (NLD) plasma.@Footnote 1@ In this chemistry, we were able to obtain only slight taper angle and small etch rate of photo-resist (PR) mask. The organic low-k etching by CH@sub 3@NH@sub 2@ / N@sub 2@ plasma, however, has also overcome the problems which were not achievable in the etching by CH@sub 4@ / N@sub 2@ plasma. In this presentation, we will discuss the concept of etching gas chemistry design and the etching mechanism on the basis of both QMS measurement results of plasma gas phase and composition evaluation results of the deposition film formed on the Si wafer surface during etching. @FootnoteText@@footnote 1@ H. Nakagawa et al, Tech. Dig. of Dry Process Symposium, Tokyo, 257 (2000).