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-ThP10
Applicability of a Hollow-electrode Plasma Jet System for Etching of Diamond-like Carbon (DLC) Films

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

Session: Plasma Etching Poster Session
Presenter: P.E. Lima, Instituto Tecnologico de Aeronautica - ITA, Brazil
Authors: P.E. Lima, Instituto Tecnologico de Aeronautica - ITA, Brazil
H.S. Maciel, Instituto Tecnologico de Aeronautica - ITA, Brazil
M. Massi, Instituto Tecnologico de Aeronautica - ITA, Brazil
R.D. Mansano, LSI - Escola Politecnica - USP, Brazil
G. Petraconi, Instituto Tecnologico de Aeronautica - ITA, Brazil
W. Urruchi, Instituto Tecnologico de Aeronautica - ITA, Brazil
C. Otani, Instituto Tecnologico de Aeronautica - ITA, Brazil
Correspondent: Click to Email
Partly in response to the challenges of etching high-aspect-ratio features, it is introduced a new plasma tool based on the hollow-electrode discharge. Plasma jets are capable of operating at relatively low gas pressures, 10@super -5@ Torr, what is in somehow advantageous in comparison with reactive ion etching (RIE) systems, because it reduces contamination from sputtered electrode materials, which eventually produces undesirable micromasks. On the other hand, the non-uniformity of the etching with plasma jets limits the applicability of this technique for microelectronic purposes. To minimize this problem, a plasma beam formed by a multi hollow-electrode system was developed in order to produce an uniform beam, which was used to etch diamond-like carbon (DLC) films. These films of approximately 1.5 µm thick were deposited on 3-inch diameter, p-type, (100) silicon wafers, by magnetron sputtering, at a deposition rate of approximately 4.5 nm/min. After being characterized, samples were separated in two batches, one of then was etched in a single hollow-electrode plasma jet and the other one was etched in a multi hollow-electrode plasma jet. During the etch processes a mechanical mask was used to cover part of the samples with the purpose of producing a step between the etched and non-etched regions. This step was measured by a perfilometer and the etch rates were determined in different positions on the samples. The results obtained with the single configuration showed a high non-uniformity in the etching. This non-uniformity was substantially reduced by using the multi hollow cathode system. The multi hollow-electrode plasma beam system revealed to be a reliable technique for DLC films processing, giving etching uniformity and etching rate characteristics as good as those obtained with usual RIE systems, with the advantage of being a simple and low cost equipment.