Gate Leakage Suppression and Contact Engineering in Nitride Heterostructures


We present a self-consistent approach to examine current flow in a general metal-polar heterostructure junction. The approach is applied to examine properties of two classes of junctions that are important in devices: (i) GaN/AlGaN/high-κ insulator structures for potential applications in very small gate devices to suppress gate tunneling current; (ii) GaN/AlGaN/LiNbO3 junctions for both n-type and p-type semiconductors with practical application for low source resistance regions. The physical parameters used for high-κ dielectrics and polarization charges reflect values typically found in ferroelectric materials. Our studies indicate that tailoring of junction properties is possible if polar oxides as thin as ~ 20Å can be achieved.

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Correspondence to Yuh-Renn Wu.

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Wu, YR., Singh, M. & Singh, J. Gate Leakage Suppression and Contact Engineering in Nitride Heterostructures. MRS Online Proceedings Library 798, 249–254 (2003).

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