Effect of pyrolysis on shrinkage properties of SU-8 polymer
Epoxy SU-8 has drawn a lot of attention during the last decades due to its promising mechanical and electrical properties. Extensive research regarding the mechanical properties of negative photoresists SU-8 has been carried out during the last decades. A lot of effort has been put into developin...
Saved in:
| Main Author: | |
|---|---|
| Other Authors: | |
| Format: | Thesis |
| Language: | English |
| Published: |
Universiti Malaysia Perlis (UniMAP)
2016
|
| Subjects: | |
| Online Access: | http://dspace.unimap.edu.my:80/xmlui/handle/123456789/41295 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Epoxy SU-8 has drawn a lot of attention during the last decades due to its promising
mechanical and electrical properties. Extensive research regarding the mechanical
properties of negative photoresists SU-8 has been carried out during the last decades. A
lot of effort has been put into developing methods to properly characterize features such
as effect of pyrolysis temperature and the pyrolysis time on shrinkage properties and
morphology of SU-8. In this work photo patterned SU-8 were fabricated on silicon
wafers by spin process for different speed steps (step (1) 250rpm and time 10sec, step
(2) 450rpm and time 30sec, step (3) 0rpm and time 5sec), then Soft baked at 95°C for
4min before cooling for 10min. Exposure to ultraviolet (UV) light was necessary to
obtain the shape of the mask, increase crosslinking degree in the irradiated areas and
stabilizes them against the action of solvents during development step. The density of
UV used was 6 mW/cm2 at 365 nm and exposure time was 5min, while the volume of
SU-8 developer was 40cm3 at 10min. Samples were cut into 2cmx2cm dimensions. The
pyrolysis was carried out in a closed quartz tube furnace in an inert nitrogen gas (N2)
flow at 1500 standard cubic centimeters per minute (SCCM) and different parameter of
temperature (350oC, 400oC, 450oC and 500oC) and time (10min and 20min). Peeling of
the SU-8 occurs due to a poor adhesion of the resist to the substrate, thicker films or
faster heating rates during the pyrolysis of SU-8. Increasing pyrolysis parameters
(temperature and time) lead to larger vertical and horizontal shrinkage, lower sheet
resistivity and roughness. The scanning electron microscope (SEM), atomic force
microscopy (AFM) and profilometer were used to examine the shrinkage and roughness
of SU-8, in order to gain an understanding of how it can affect the shrinkage properties
and determine the optimized pyrolysis conditions. |
|---|