“…Precisely machined micro-features have been utilized widely with the development of micro-fabrication technologies such as micro-cutting [1,2], micro-electrical discharge machining (EDM) [3,4], micro-and nano-lithography [5,6], nanoimprint [7] and micro-molding [8]. In particular, more precision micro-features with high aspect ratios represented by deep micro-holes and micro-slits are utilized for precision tools and measuring instruments that require sub-micrometric or nanometric dimensional accuracies.…”