BCB/polyimide process

[Onur Fidaner]

Mathilde,

We've done some work on BCB processing some time ago. You can check the 
link below for a paper of ours that includes our recipe as well. One 
suggestion about the chemical: Dow chemical (supplier of BCB) guarantees a 
shelf life of at least one year from the date you purchase. Though, if you 
ask them they may be able to provide you with an extended one so you have a 
chance to use it longer. Also, we've used the chemical up to two years past 
the expiration date and still got satisfactory results for 2 um mesas.

We used headway to spin the chemical and then the bluem oven for the anneal 
cycle described in the data sheet. We found it useful to protect the 
backside of the wafer/piece with some blue sticky tape during spinning to 
avoid cleaning later.

Thanks,

Onur Fidaner

the paper:
http://ieeexplore.ieee.org/iel5/66/30318/01393058.pdf?tp=&arnumber=1393058&isnumber=30318




At 02:56 PM 5/23/2007, you wrote:
>Hello,
>
>I am looking into planarizing 5 to 10 um height mesas, either with BCB
>or polyimide (photosensitive or etchable). I was wondering if I could
>borrow some BCB or polyimide from somebody to first try my processing.
>Also, if somebody is interested in sharing BCB or polyimide in the
>long run, we could split the cost of the material as they are very
>expensive chemicals.
>
>I will also appreciate any advice regarding using any of these
>materials, or processing recipes. Thanks in advance for your help.
>
>Best regards,
>Mathilde