A semiconductor substrate is provided, and at least one first mask is formed above the semiconductor substrate. The first mask blocks at least one semi-insulating region. A second mask is thereafter formed on a surface of the semiconductor substrate. The second mask covers the semi-insulating region....http://www.google.fr/patents/US7064048?utm_source=gb-gplus-shareBrevet US7064048 - Method of forming a semi-insulating region
