SEMICONDUCTOR QUANTUM POINT-CONTACT FABRICATED BY LITHOGRAPHY WITH ANATOMIC-FORCE MICROSCOPE

We report on the experimental realization of a quantum point contact i n a semiconductor heterostructure by lithography with an atomic force microscope (AFM). A thin, homogeneous titanium film on top of the chip surface was patterned by local anodic oxidation, induced by a current applied to an n-doped AFM tip. We demonstrate that self-aligned gate structures in the sub-micron regime can be fabricated with this techni que. (C) 1997 American Institute of Physics. [S0003-6951(97)02642-9].