The quest for even smaller and better-controlled semiconductor nanostructures calls for improved nanofabrication techniques. We succeeded in patterning metallic and semiconducting nanostructures by using local oxidation-mediated via a voltage between a conducting surface and a close-by tip of an atomic force microscope (AFM). In particular, we were able to control the electronic properties of quantum point contacts, long quantum wires as well as single electron transistors embedded in an AlGaAs two-dimensional electron gas (2DEG). This article focuses on the technological aspects of this novel nanofabrication method.