Question for pmma users

Hello labmembers,

Perhaps some of you have direct experience using pmma in anisole as a resist using UV lithography and can give me some useful numbers. From what literature I can find online, ebeam exposure or even uv exposure will make it positive, however, upon extensive exposure, crosslinking will occur to convert the pmma into negative tone (exposed features will not dissolve away in developer).

 

I am new to pmma so I am not sure how long the UV exposure is in UV, seconds or tens of minutes even to get the crosslinking for negative tone. I am not concern at all about critical dimension or over exposure. I just want to either develop away the exposed part  (positive tone) or keep the exposed part (negative tone) .

 

I will trial and error it but getting some insight from you first would be much appreciated.

 

Thank you

 

 

 

Regards,

Sonny

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"What makes the desert beautiful," said the Little Prince ,"is that somewhere it hides a well ."

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Sonny Vo

Ph.d candidate

Department of Applied Physics, Stanford University

(626) 216-4597

Harris Research Group: http://snow.stanford.edu/index.html