Photoresist Stripping for Fun and Profit

December 2005

Photoresist Stripping for Fun and Profit

The PCMI was kind enough to invite me to talk at their Fall Conference about one ofthe areas of technology we like to think we are experts on… photoresist stripping. But, given that I talk WAY too fast, I decided to expand the talk to the entire photoresist related process.

Photoresist is obviously the key to the PCMI process, and most ofthe photoresists used in PCM today are the negative working dry film type, which are developed in 1% carbonate solutions and stripped in strong alkali. Photoresist can be thought of as a mass of unconnected spaghetti strands packed together to form the dry film. These spaghetti strands are reactive, and when they are hit by light, they link together (chemists call this cross-linking, to confuse non-chemists), to form a solid, nonwater soluble mass.

Rudy Sedlak, RD Chemical Company, Mountain View, CA, USA