Hi,

     It depends on what do you mean by strength. You can say how stronger
the film in two ways 1)is from its properties or 2) how stronger the film is
sticked to the substrate. You can use techniques like nano-indentation to
analyse the properties of thin film like 1)hardness 2) Youngs modulus
3)Poisson's ratio.   If you are looking for the adhesion strength of the
film, you can use micro-scratcher or tape pull-off test to test the films
adhesive and cohesive strength to the substrate.

Regards,

Arun



-----Original Message-----
From: [email protected]
[mailto:[email protected]]On Behalf Of Suhua Jiang
Sent: 13 January 2006 08:41
To: [email protected]
Subject: [mems-talk] How to test the strength of Copper thin film?

After I deposited 1 um copper thin film on Ta/Si-sub, How can I measure the
strength of the copper layer?