by ahgu » Wed Jul 11, 2018 2:11 pm
I don't know how Rallisson did his pin coating. I cannot get uniform coating with DCG. See picture below.
solution about 5-25-120. Temp 40-50C. veil coat it first then spin at 80RPM Under regular light, it is very obvious it is not even.
- coating2.jpg (155.87 KiB) Viewed 29259 times
I also tried mold coating. Looks good until developing, Get those circular flow pattern left after developing. Shim is about 50um. Final dried thickness about 7-8um thick.
- coating3.jpg (160.34 KiB) Viewed 29259 times
Also tried Meyer bar, first try left thread mark, heat it up, no more thread mark, but uneven.
DCG solution is pretty thick even at 50C, it is very resistant to flow. I wonder how you guys get it to flow uniformly.
I don't know how Rallisson did his pin coating. I cannot get uniform coating with DCG. See picture below.
solution about 5-25-120. Temp 40-50C. veil coat it first then spin at 80RPM Under regular light, it is very obvious it is not even.
[attachment=1]coating2.jpg[/attachment]
I also tried mold coating. Looks good until developing, Get those circular flow pattern left after developing. Shim is about 50um. Final dried thickness about 7-8um thick.
[attachment=0]coating3.jpg[/attachment]
Also tried Meyer bar, first try left thread mark, heat it up, no more thread mark, but uneven.
DCG solution is pretty thick even at 50C, it is very resistant to flow. I wonder how you guys get it to flow uniformly.