[mems-talk] 20um features using AZP4620

[Haixin Zhu]

Dear Chad,

U are right. Though I succeeded in making 38um thick pattern with 20um feature size, there is still some problem with undercut of the pattern and bottom residue. I will try AZ 9260, and hoping you can send me your processing traveler so I can use as reference and start point.

Thanks

Michael
 

-----Original Message-----
From: mems-talk-bounces at memsnet.org [mailto:mems-talk-bounces at memsnet.org] On Behalf Of Brubaker Chad
Sent: 2008年6月13日 13:26
To: General MEMS discussion
Cc: Brubaker Chad
Subject: Re: [mems-talk] 20um features using AZP4620

There is actually a problem with trying to use AZP4620 to that thickness, and one of the other responders alluded to it - transparency.

For layers thicker than about 15 - 20 µm, you'll already start to see some issues with light penetration into an AZP4620 film (the develop behavior becomes much less linear).  Beyond 25 µm, you begin to have extreme difficulties in clearing the bottoms of exposed regions, because the light is just not penetrating that far.

The suggestion of AZ9260 is a good one - this was AZ's (or Clariant's, at the time) update to AZP4620, once it became apparent that people were using the material for thicker-and-thicker films.  Its two primary differences from AZP4620 is greater transparency (I've produced 5:1 aspect ratios) and an included leveling agent to produce smoother and more uniform films.  I myself have single coated this material to 65 µm thick, and patterned it (my minimum CD was somewhere between 10 and 15 µm).

Best Regards,
Chad Brubaker