H. Sugimura et al., MASKLESS PATTERNING OF SILICON SURFACE-BASED ON SCANNING TUNNELING MICROSCOPE TIP-INDUCED ANODIZATION AND CHEMICAL ETCHING, Applied physics letters, 65(12), 1994, pp. 1569-1571
A microprocessing method for silicon (Si) without photolithography is
proposed. The method consists of only two processes. Hydrogen-terminat
ed Si surfaces (Si-H) were first locally anodized using scanning tunne
ling microscopy (STM). The non-anodized surfaces were then etched chem
ically in potassium hydroxide solution. The anodic oxide produced with
the first process performed as an etching mask. The height of the etc
hed pattern of approximately 50 nm was much larger than the thickness
of the anodic oxide. Humidity effect on STM tip-induced anodization of
Si-H is also shown. The area of the anodization was enlarged with inc
reasing humidity, and the spatial resolution became worse.