Pattern fabrication of chemically amplified resist on an interdigitated array electrode

The patterning of the chemically amplified resist SAL601 on an interdigitated array electrode (IDA) has been carried out. When direct current is applied to resist films during the post-exposure baking process, the resist sensitivity is low near the edge of the cathode on the IDA and there is a semicircular cavity in a cross-sectional-developed pattern. It is considered that catalytic protons generated during exposure reduce, becoming electrically neutral on the cathode surface and losing their catalytic ability for crosslinking reactions. From the size of the cavity, the acid diffusion coefficient can be roughly estimated to be 70 nm2/s.