Hi All,

Most times you can strip resists with hot H2SO4 at 130c not 180c. Once the H2SO4
is at 130c you add some Hydrogen Peroxide very slowly, add 200ml for a 3 gallon
bath. Then very slowly place the wafers to be cleaned in the hot H2SO4. MAKE
SURE THE WAFERS ARE DRY or it will explode. Hot H2SO4 is very dangerous and
never put any water in the solution. The H2SO4 dissolves the resist and the H2O2
creates CO2 and everything is gone.

Rick Morrison


-----Original Message-----
From: mems-talk-bounces+rmorrison=draper.com@memsnet.org [mailto:mems-talk-
bounces+rmorrison=draper.com@memsnet.org] On Behalf Of Jie Zou
Sent: Wednesday, June 23, 2010 11:49 PM
To: General MEMS discussion
Subject: Re: [mems-talk] Removing hard-baked photoresist

Holy cow... are you sure this won't explode?

Jie

On Wed, Jun 23, 2010 at 1:26 PM, Jesse D Fowler  wrote:

> Piranha (in my case 4:1 H2SO4 : 30%H2O2) boils at 160C. It is much more
> aggressive at this temperature. (also very dangerous!)
>
>
> ----- original message ----
> From: antwi nimo 
> To: ameya.g@gmail.com, General MEMS discussion 
> Date: 06/23/2010 09:47 AM
> Subject: Re: [mems-talk] Removing hard-baked photoresist
>
>
> A mixture of H2SO4 and H2O2 at a temperature of  ~180celsius can remove
> the resist...This solution is used the remove resist when making glass
> mask...I am sure it can remove this resist to.....i hope this information
> helps,
> Nimo

*  Zou Jie (Jay)
*  Department of Physics
*  University of Florida
*  Tel: +1-352-846-8018
*  Email: zoujiepku@gmail.com
*  Homepage: http://plaza.ufl.edu/zoujie/