We investigated the formation of nanowhiskers by means of air plasma dry et
ching using diamond films of two different kinds: as-grown diamond films an
d films with molybdenum (Mo) deposits. As for the as-grown diamond films, n
anowhiskers were found to form preferentially at grain boundaries of diamon
d crystals. Auger depth profile analysis of the etched films revealed a pro
gressive enrichment by Mo toward the whisker tip, resulting from accidental
sputtering of Mo substrate holder. With dry etching of diamond films with
preformed Mo deposits, well-aligned whiskers 100 nm in diameter were found
to form uniformly over the entire film surface with a population density of
30/mu m(2). From these findings, it follows that Mo deposits serve as micr
omasks for the formation of the nanowhiskers. It was; also confirmed that t
hese whiskers showed excellent field-emission behavior.