HSQ Writing Test

1. HSQWritingTest SurfaceCleaning:DipinCD30,10min Spin-coating:6000rpm (2000rpm/s), 60s Bake: 80’C for 4min Dose Test: 750, 1000, 1250, 1500, 2000 uC/cm2 Developing: 80’C (measured to be 50’C) HDMS for 30s

2. 750 uC/cm2 1 layer lines on Ni 750 uC/cm2 2 layer lines on Ni 1000 uC/cm2 1 layer lines on Ni 1000 uC/cm2 2 layer lines on Ni

3. 1250 uC/cm2 1 layer lines on Ni 1250 uC/cm2 2 layer lines on Ni 1500 uC/cm2 1 layer lines on Ni 1500 uC/cm2 2 layer lines on Ni

4. 1750 uC/cm2 1 layer lines on Ni 1750 uC/cm2 2 layer lines on Ni 2000 uC/cm2 1 layer lines on Ni 2000 uC/cm2 2 layer lines on Ni

5. Conclusion • With one layer writing on the Ni lines, the writing dosage should be larger than 1750 uC/cm2 • With two layers writing on the Ni lines, the writing dosage should be between 1000 – 1500 uC/cm2 • For all dosage test, the smallest fin width is around 28~33nm. (For smaller dosage, the smallest fin that exist is ~ 30nm. For larger dosage, even though all 8 fins may remain there, but the smallest is still ~ 30nm. This indicates that with current writing conditions, fin length, developing agent, and HSQ thickness 80nm, it’s difficult to write fin width around 20nm, as the aspect ratio is high and the fin will not adhere well.) • I also tried to write directly the same pattern with same dosage directly on substrate, besides the Ni lines. The results are the same, which means that for this writing condition, the Ni lines didn’t influence much on the writing. • I also tried with room temperature developing on another set of samples with the same dose test. With same developing time, the fins shown less developing but no improvement on the resolution.