A typical method for sub-micrometer compound semiconductor dry etching utilizes polymethylmethacrylate (PMMA) to transfer patterns to SiO2 as intermediate masks, which limits its ability to obtain etching resolutions approaching sub-10 nm. We report a new approach for direct sub-10 nm pattern transfer using sol-gel derived spin-coatable ZrO2 resist as the mask. The optimal dose of ZrO2 resist is ∼160 mC cm-2. The sample InP compound semiconductor etching selectivity to ZrO2 is over 13:1, with high aspect ratio of 35:1. The smallest etching feature is 9 nm. These results will be very useful for realizing various challenging nanoscale photonic and electronic devices and circuits.
ASJC Scopus subject areas
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering
- Electrical and Electronic Engineering