C-MEMSin which patterned photoresist is pyrolyzed in an inert environment at high temperatureconstitutes a powerful approach to building 3D carbon microelectrode arrays for 3D micro battery applications. High aspect ratio carbon posts are achieved by pyrolyzing SU-8 negative photoresist in a simple one step process.
C-MEMS technology is useful for 3D microarray due to C having attractive properties. These include mechanical durability, electrical conductivity, and chemical stability. High aspect ratio with low cost is obtained by using SU-8 with conventional photolithography followed by pyrolysis.
High aspect ratio
Near vertical sidewalls
>200 µm in a single spin coat
No popping or voids created in resist structures after exposure
Conductivity after pyrolysis of 1000°C for 1 hour, the SU-8 is similar to glassy carbon
Pyrolysis of SU-8
a. SU-8 posts; b. Pyrolized SU-8 posts; c. & d. 3D C-MEMS posts
1. Coat and bake SU-8 2100
2. The SU-8 layer is exposed.
3. The SU-8 layer is post exposure baked.
6. Carbon structures
SEM images and C-MEMS process courtesy of Chunlei Want@FIU and Marc Madou@UCI