• Graupeter, Sarina
• Schilling, Marcel
• Susilo, Norman
• Pietsch, Mike
• Kneissl, Michael
• Martin, Robert
• Foronda, Humberto M.
• Irmscher, Klaus
• Hunter, Daniel A.
• Enslin, Johannes
• Wernicke, Tim
• Muhin, Anton
• Sulmoni, Luca

Abstract

In this work, the growth and conductivity of semipolar AlxGa1−xN:Si with (11-22) orientation are investigated. AlxGa1−xN:Si (x = 0.60 ± 0.03 and x = 0.80 ± 0.02) layers were grown with different SiH4 partial pressures, and the electrical properties were determined using Hall measurements at room temperature. The aluminum mole fraction was measured by wavelength dispersive x-ray spectroscopy and x-ray diffraction, and the Si-concentration was measured by wavelength dispersive x-ray spectroscopy and secondary ion mass spectroscopy. Layer resistivities as low as 0.024 Ω cm for x = 0.6 and 0.042 Ω cm for x = 0.8 were achieved. For both aluminum mole fractions, the resistivity exhibits a minimum with the increasing Si concentration, which can be explained by compensation due to the formation of cation vacancy complexes at high doping levels. The onset of self-compensation occurs at larger estimated Si concentrations for larger Al contents.

Topics

• resistivity
• phase
• x-ray diffraction
• aluminium
• wavelength dispersive X-ray spectroscopy
• vacancy