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Plasma etch defect issues

2001

I am running a Plasma etch tool with chlorine based. The other gases used are Helium and Oxygen. I used the Plasma etch for Photomask chrome layer etching. Currently I'm facing a problem of massive chrome defect but managed to reduce them to less then 100 defect after cleaning all the chambers.

What further action can I to reduce the chrome defects? Should I adjust the RIE and ICP RF power or gasses composition? If yes where should I start first?

Azman Musa
- Singapore

Thoroughly partition all areas where your mask can pick-up defects, is it definitely the process chamber? Consider cleaning the load-lock which can become corroded by out gassing of Cl from the resist. Check all O-rings and consider changing to chem-raz or cal raz. Partition the chamber, gas-on, no gas-on, move any internal parts which can move, final thing is to consider removing and servicing your turbo-pump.

Kevin Pears
- England
2001

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