Hi Angie,
Im using AZ9260 as well, however without the EBR Thinner.
I made the swing curves myself to verify first the behavior of my resist.
I can provide you this information.
What is important though, is the dilution of the Developer AZ400K.
I'm working with 1:3 Developer:Water at 28C and 700mJ/cm2 which would equal
an exposure time of around 2 minutes in your case with a output power of
6mW/cm2. But I don't know how the thinner interferes with the exposure.
Maybe the diffusion of the DNQ compound is due to the thinner facilitated
and the exposure has a bigger effect.
Cheers,
Sebastian
-----Original Message-----
From: [email protected] [mailto:[email protected]]
On Behalf Of Angeliki Bouloukou
Sent: Friday, August 24, 2007 12:08 PM
To: [email protected]
Subject: [mems-talk] Stability of AZ9260
Does anyone have experience using various dilutions of the AZ9260 resist.
I have been using the resist undiluted and in an in-house 4:1 and a 1:1
dilution with EBR, achieving FTs of 6im, 3im and 1im respectively.
With the 1im film I am trying to achieve a minimum feature (trenches) of
1im. However the resist seems to be completely unstable. The process window
for exposure is 1-2 seconds and even this still varies along the typical
2x2cm2 area of my usual sample size.
I understand that the AZ9260 has an aspect ration of 6:1, however I have
been unable to reliably resolve 1im features with it or any of it' s
dilutions.
Another effect I am experiencing is that development rates for small
features seem to decrease around the optimum exposure time. That is to say,
an underexposed or overexposed sample requires longer than the optimised
development time.
Is this a behaviour to be expected of this resist?
A final issue with the resist is that both dilutions seem to need the same
exposure time. I haven' t managed to find the swing (interference) curves
for AZ9260 and was wondering if anyone knows where I could find this data.
An example of myr current process parameters (for FT: 1im) is as follows:
Mask aligner: Karl Suss MA4 with UV300 optics operating at 6mW/cm2
Spin parameters: 4000rpm, 60sec
Prebake: 100oC hotplate 1min/im
Re-hydration: 10min
Exposure: 53sec
Development: 1min/im
Has anyone experienced similar problems? Any useful suggestions?
