Prakt. Met. Sonderband 38 (2006) 409 
additional line markers fabricated by FIB milling, which defined the position where the 
trench model (mask) should be located (Fig. 10). 
720nm 
P———— 
Fig. 10. AFM image of the test structure with markers. 
FM ti 
a (Fig, In Fig. 11 we present the deconvoluted three-dimensional image of the AFM microtip, 
5m the which was calculated using sample and AFM data shown in Fig. 8. In addition, we depict 
Sion) two cross sections of the investigated probe determined in X and Y scanning directions. In 
this case we obtain a probe radius in X and Y direction of 50 nm and 70 nm, respectively. 
However, the small features at the probe apex enable the application of the tested tip to 
measurements of very flat surfaces (e.g. of DNA structures deposited on a mica surface). 
Moreover it should be stressed that the SEM based investigations of this very small apex 
feature, whose size is in the range of 10 nm, are tedious and difficult. 
ig | 
e 
tween nr 
nk, the o ; 
ratio or » tre 
e hole. » 
1d part x 
. 9b). J 
Sircular 1 0.0 nm 
led. To 
Cross- Er TE ETE 
zation, Fig. 11. The results of the scanning probe visualization. 
enGL. 
hssible An inaccuracy of tip characterization results from the uncertainty of defining the size of the 
rder to real circular depression as input for the AFM data evaluation. Moreover, the circular 
(mask) depression is a poor calibration standard for square pyramidal tips (produced e.g. as SizN4 
Jtilized tips), as the deconvolution process gives rounded shapes of the probes.