Process nano scale mechanical properties measurement of thin metal films using a novel paddle cantilever test structure

TL;DR

This paper introduces a novel paddle cantilever test structure for measuring nano-scale mechanical properties of thin metal films, utilizing electrostatic deflection and capacitance measurement techniques.

Contribution

It presents a new paddle-shaped cantilever design and a measurement method for assessing residual stress and mechanical behavior of ultra-thin metal films.

Findings

Successful fabrication of nano-scale paddle cantilever structures

Capacitance-based deflection measurement for strain analysis

Quantitative residual stress measurements on thin metal films

Abstract

A new technique was developed for studying the mechanical behavior of nano-scale thin metal films on substrate is presented. The test structure was designed on a novel "paddle" cantilever beam specimens with dimensions as few hundred nanometers to less than 10 nanometers. This beam is in triangle shape in order to provide uniform plane strain distribution. Standard clean room processing was used to prepare the paddle sample. The experiment can be operated by using the electrostatic deflection on the paddle uniform distributed stress cantilever beam and then measure the deposited thin metal film materials on top of it. A capacitance technique was used to measurement on the other side of the deflected plate to measure its deflection with respect to the force. The measured strain was converted through the capacitance measurement for the deflection of the cantilever. System performance on the residual stress measurement of thin films are calculated with three different forces on the "paddle" cantilever beam, including the force due to the film, compliance force and electrostatic force.