Neural interface technologies are evolving rapidly to better understand brain function and treat neurological diseases. Recent efforts focus on (1) minimally invasive approaches and (2) integrating additional functions such as optical interfacing. While novel materials have potential, clinical use requires extensive validation. This talk introduces a method for creating transparent, flexible neural electrodes using conventional gold, enabled by polymer-metal atomic interaction. By thinning gold electrodes below 10 nm while maintaining electrical continuity, we achieved high transparency. Applications in biomedical fields will also be discussed.