Precision etching of aluminum conductors in the technology of switching devices of microsystems technology

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Abstract

Experimentally obtained precision technology of forming a controlled profile of aluminum conductive paths with a specified resistance is presented. The technology is based on anisotropic plasma-chemical etching of aluminum in the gas mixture BCl3 – Cl2 with subsequent precision adjustment of path resistance by the “dry” plasma-chemical method. It is shown that in order to ensure the highest quality plasma chemical etching of aluminum with minimal under etching under the photoresist mask, with minimal inclination of the aluminum conductive path profile and absence of defectiveness of the etching pattern and stratified areas, it is necessary to use a multistage iterative technological process with technological operations of surface preparation before etching and operations of polymer and photoresist removal after etching.

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About the authors

P. I. Didyk

UVN Scientific and Production Enterprise

Author for correspondence.
Email: Felix_engine@mail.ru
Russian Federation, Moscow

A. A. Zhukov

Moscow Aviation Institute

Email: zhukovаа@mail.ru
Russian Federation, Moscow

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Supplementary files

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2. Fig. 1. Right angle SEM photographs of the aluminium conductive track after aluminium etching and before polymer removal

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3. Fig. 2. Plasma chemical etching rate of aluminium at varying ratio of BCl3 to Cl2

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4. Fig. 3. SEM photographs of aluminium conductive tracks after aluminium etching and polymer removal: (a) at right angle; (b) at 45° angle

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5. Fig. 4. Variation of aluminium track resistance from time of plasma chemical etching in BCl3

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