Statistical investigation of dislocation induced leakage current paths in AlGaN/GaN HEMT structures on Si and the impact of growth conditions

Abstract Threading dislocations in the AlGaN-barrier of four pairwise differently grown AlGaN/GaN high electron mobility transistor structures on Si were investigated with respect to their structural and electrical properties direct comparison simultaneously ensuring statistical significance results. Portions pure screw mixed type observed serve as leakage current paths be clearly dependent growth conditions like AlN nucleation layer temperature. The role impurity segregation at dislocation cores due growth-dependent locally characteristic strain fields for example induced by specific reactions interface is discussed origin.