Medusa 82 with photoacid generator (PAG)

One disadvantage of HSQ and Medusa 82 is the comparably low sensitivity, which can however be increased by an addition of photoacid generators.

Sensitivity increase by a factor of 20 after addition of PAG (30 kV)

• Resist: SX AR-N 8200.06/1 – 100 nm
• Coating: 60 s 4000 rpm
• Soft-bake: 15 min @ 120°C
• Exposure: 30 kV
• Development: 90 s AR 300-44; 23 °C
• Stopping: 30 s DI-water

Sensitivity increase by a factor of 5 after addition of PAG (100 kV)

• Resist: SX AR-N 8200.06/1 – 100 nm
• Coating: 60 s 4000 rpm
• Soft-bake: 10 min @ 130 °C
• Exposure: 100 kV
• Development: 90 s AR 300-44; 23 °C
• Stopping: 30 s DI-water

In the case of e-beam exposure at 30 kV, the sensitivity could be increased by a factor of 20, and at 100 kV by about a factor of 5. The sensitivity can be adjusted by varying the PAG content in the resist.

Sensitivity increase by a factor of 5 after addition of PAG (100 kV)

Interestingly, the sensitivity of the standard resist Medusa 82 (without PAG addition) can also be increased by a PEB (for example 5 min at 180 °C; see diagram, black line). The resist patterns obtained differ only slightly as compared to patterns with addition of PAGs (see Medusa: Influence of post exposure bake).