Brain Science Institute;
Korea Institute of Science and Technology(KIST);
Seoul 02792;
South Korea;
Division of Electrical Engineering;
College of Engineering;
Korea University;
Seoul 02841;
South Korea;
Micro/Nano Fabrication Center;
KIST;
Seoul 02792;
South Korea;
Division of Bio‑Medical Science&Technology;
KIST School;
University of Science&Technology(UST);
Seoul 02792;
South Korea;
Microneedle; Various heights; Cross-sectional shapes; Isotropic etch; Deep reactive ion etching;