International Business Machines Corporation

Wolf D Ruh

Rolf Schaefer

Georg Kraus

Gerhard Trippel

Frank Druschke

Arwed Brunsch

Ulrich Kuenzel

Jochen Schneider

According to this method, copper is dry etched in a glow discharge containing compounds with at least one methyl or methylene group, particularly at temperatures close to room temperature. The method is applied in particular for making conductors on or in module substrates or circuit cards, solder spots, and the wiring of magnetic thin films.

Method of dry copper etching and its implementation

Direct method for measuring the magnetostriction constant .lambda..sub.s of soft magnetic and isotropic magnetic materials. A thin film sample is cantilevered and clamped at one edge. Under the influence of a magnetic AC field and the magnetostriction effect of the sample material, the free end of the cantilevered sample is deflected and oscillates with twice the frequency of the AC field. The resonance amplitude a.sub.res is measured by using a laser beam impinging upon the oscillating sample and measuring the reflected beam amplitude by means of a position-sensitive photodiode. The AC output signal of the photodiode is proportional to the sample amplitude. The magnetostriction constant .lambda..sub.s is directly proportional to the resonance amplitude a.sub.res multiplied by a constant factor which depends on known geometry and properties of the sample material.

Apparatus for measuring magnetostriction constant

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Munich, Georgia

Wolf D Ruh