Ij. Cho et al., Atomic force microscope probe tips using heavily boron-doped silicon cantilevers realized in a (110) bulk silicon wafer, JPN J A P 1, 39(12B), 2000, pp. 7103-7107
A new method of fabricating atomic force microscope (AFM) probe tip is pres
ented. In this process, the probe tips were implemented using self-aligned
heavily boron-doped silicon cantilevers in a [110] bulk silicon wafer. In t
his structure, a stress-fi ee cantilever can be easily defined by selective
etch stop by the heavily boron-doped region in an anisotropic silicon etch
ant. The proposed tips do not require expensive silicon on insulator (SOI)
wafers and double-side alignment. The probe tip dimensions can be exactly d
efined regardless of wafer thickness by the self-aligned etch from the fron
t side. In addition: the cantilever thickness can be easily controlled by a
djusting the diffusion time, and fabricated at low cost by using bulk silic
on wafers. The fabricated probe tips showed resonant frequencies of 71.420
kHz with a 1.8-mum-thick probe tip and 122.660 kHz with a 3.0-mum-thick pro
be tip. Using the two fabricated probe tips, we successfully demonstrate im
age scanning of a 1 mum grating reference sample in contact and noncontact
modes, respectively.