Micro-tensile tests on micromachined metal on polymer specimens: elasticity, plasticity and rupture

TL;DR

This paper introduces a novel micro-tensile testing method for micromachined metal-polymer specimens, enabling detailed analysis of their elasticity, plasticity, and rupture behaviors relevant to MEMS device applications.

Contribution

It presents a new deformation bench test with micromachined specimens for mechanical characterization of MEMS materials, including cyclic testing for dynamic and reliability assessments.

Findings

Validated the deformation bench for dynamic material characterization

Demonstrated mechanical behavior of electroplated copper on polymer substrates

Established reliability testing protocols for microstructures

Abstract

This study is focused on the mechanical characterization of materials used in microelectronic and micro- electromechanical systems (MEMS) devices. In order to determine their mechanical parameters, a new deformation bench test with suitable micromachined specimens have been developed. Uniaxial tensile tests were performed on "low cost" specimens, consisting in electroplated thin copper films and structures, deposited on a polimide type substrate. Moreover, a cyclic mechanical actuation via piezoelectric actuators was tested on the same deformation bench. These experiments validate the device for performing dynamic characterization of materials, and reliability studies of different microstructures.