M. Tanimoto et O. Vatel, KELVIN PROBE FORCE MICROSCOPY FOR CHARACTERIZATION OF SEMICONDUCTOR-DEVICES AND PROCESSES, Journal of vacuum science & technology. B, Microelectronics and nanometer structures processing, measurement and phenomena, 14(2), 1996, pp. 1547-1551
Kelvin probe force microscopy was applied to the characterization of A
l0.3Ga0.7As/GaAs multilayer structures and Si-pn structures. The spati
al resolution of Kelvin probe force microscopy measurement was investi
gated using cleaved Al0.3Ga0.7/As/GaAs structures. A 40-nm-thick Al0.3
Ga0.7As layer was resolved with potential difference of 15 mV. It was
found that the measured potential is sensitive to the Al mole fraction
for AlGaAs. Two-dimensional delineation of Si-pn structures was succe
ssfully carried out on the topmost and the cleaved surfaces. A decreas
e of a depletion-layer width with increasing the intensity of light il
luminating the sample was observed. It was confirmed through investiga
ting illumination effects on various kinds of structures that the meas
ured Kelvin probe force microscopy potential reflects the surface band
structure of the sample. A lateral impurity profile under the ion imp
lantation mask was extracted from the two-dimensional potential image
obtained on the cleaved pn junction by calibrating with the impurity c
oncentration profile measured by the spreading resistance method. (C)
1996 American Vacuum Society.