Fabrication of two-dimensional electron systems by focused ion beam doping of III/V semiconductor heterostructures.

Two-dimensional electron systems have been fabricated by focused ion beam implantation of Si dopant ions in undoped III/V heterostructures grown by molecular beam epitaxy. With this method, lateral patterning of two-dimensional electron gases is possible while the planarity of the sample surface is conserved. In this paper, we present a systematic study of this technique and discuss its potential for applications. In detail, different base material systems are experimentally investigated and compared. The electronic properties of the samples are characterized by low-field Hall measurements, capacitance-voltage spectroscopy, and measurements of the longitudinal magnetoresistance at low temperatures. The dependence of the electronic properties on the implantation parameters is discussed. [ABSTRACT FROM AUTHOR]