CHARACTERIZATION OF SEMICONDUCTOR HETEROSTRUCTURES AND QUANTUM DOTS BY FRICTION FORCE MICROSCOPY

The capability of friction force microscopy to obtain compositional ma ps of semiconductor structures grown by molecular beam epitaxy was stu died. Experiments on InP/InGaAs multiquantum wells determined a compos itional spatial resolution of 3 nm. Additionally, variations in indium concentration smaller than 10% were detected in InxGa1-xAs structures . Friction maps of InAs and InSb quantum dots on InP(001) are also pre sented. The experimental results show that the frictional force is sen sitive to the presence or absence of a wetting monolayer. Based on the se experiments, the potential of friction force microscopy to develop a spatially resolved spectroscopy is discussed. (C) 1998 Elsevier Scie nce B.V.