Hi Li,

I have successfully lifted-off metal films of similar thickness by a 20-30 min
ultrasonic dip. I don't think it will damage the film.

Regards,

Harsh Sundani
Graduate Research Assistant, University of Toledo, Toledo, Ohio.


> Date: Mon, 15 Mar 2010 23:20:29 -0400
> From: anli5210@gmail.com
> To: mems-talk@memsnet.org
> Subject: [mems-talk] Does ultrasonic damage metal film during lift-off?
>
> Hi all,
>
> I'm doing lift-off using ultrasonic bath after soak my samples in NMP
> overnight. However, some parts are difficult to be lifted off.
> Thus, I increased the ultrasonic cleaning duration. But I'm afraid a long
> ultrasonic cleaning (20-30min) might damage the metal film which is 150nm
> sputtered Al.
>
> Would that be a problem?
>
> Thanks,
>
> Li. Zhang