Anisotropic Reactive Ion Etching of Aluminum Using Cl sub 2 , BCl sub 3 , and CH sub 4 Gases

• Published in: Journal of the Electrochemical Society Vol. 137; no. 1; pp. 249 - 252
• Main Authors: Lutze, J W, Perera, A H, Krusius, J P
• Format: Journal Article
• Language: English
• Published: United States 01.01.1990
• Subjects: 360601 - Other Materials- Preparation & Manufacture; 360602 - Other Materials- Structure & Phase Studies; 656003 - Condensed Matter Physics- Interactions between Beams & Condensed Matter- (1987-); ALKANES; ALUMINIUM; ANISOTROPY; AUGER ELECTRON SPECTROSCOPY; BORON CHLORIDES; BORON COMPOUNDS; CHLORIDES; CHLORINE COMPOUNDS; CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DATA; ELECTRON SPECTROSCOPY; ELEMENTS; ETCHING; EXPERIMENTAL DATA; HALIDES; HALOGEN COMPOUNDS; HYDROCARBONS; INFORMATION; MATERIALS SCIENCE; METALS; METHANE; NUMERICAL DATA; ORGANIC COMPOUNDS; PLASMA; SOLID-STATE PLASMA; SPECTROSCOPY; SURFACE FINISHING; THIN FILMS
• ISSN: 0013-4651; 1945-7111
• DOI: 10.1149/1.2086376

A technique for anisotropically etching fine line patterns in Al films using the gas combination Cl sub 2 :BCl sub 3 :CH sub 4 is explored. The process is designed to avoid the use of CCl sub 4 and CHCl sub 3 , both of which are known to be strong carcinogens. The etch is characterized by making use of statistically designed experiments to optimize the etch rate, selectivity, and anisotropy of the etch. The etching mechanisms is explored by the use of Auger electron spectroscopy to study polymer sidewall deposits, caused by the use of CH sub 4 and an organic mask, which prohibit undercutting. Using this etch, the anisotropic etching of fine line features in Al films has been demonstrated with minimum lines and spaces of 500 and 300 nm, respectively. Graphs, Spectra, Photomicrographs. 9 ref.--AA