We present the results on piezoelectric and pyroelectricdoping in AlGaN-on-GaN and GaN-on-AlGaN heterostructures and demonstrate p-GaN/AlGaN structures with accumulation hole layer. Our results indicate that polarization charge can induce up to 5×1013 cm−2 holes at the AlGaN/GaN heterointerfaces. We show that the transition from three-dimensional (3D) to two-dimensional (2D) hole gas can be only achieved for hole sheet densities on the order of 1013 cm−2 or higher. At lower densities, only 3D-hole accumulation layer may exist. These results suggest that a piezoelectrically induced 2D-hole gas can be used for the reduction of the base spreading resistance in AlGaN/GaN-based heterostructurebipolar transistors.
Published in Applied Physics Letters, Volume 76, Issue 21, 2000, pages 5075-5078.
©Applied Physics Letters 2000, American Institute of Physics (AIP).
Shur, M. S., Bykhovski, A. D., Gaska, R., Yang, J. W., Simin, G., & Khan, M. A. (22 May 2000). Accumulation Hole Layer in p-GaN/AlGaN Heterostructures. Applied Physics Letters, 76 (21), 3061-3063. http://dx.doi.org/10.1063/1.126579