The Research Of The Modulation GaSb Semiconductor Contact Barrier

GaSb semiconductor compounds because of their band structure characteristics, It has broad applications in electronic and optoelectronic devices in the future.In the metal contact with the GaSb semiconductor, the metal and semiconductor of contact barrier has important influence to the device. The caused by the semiconductor surface state of Fermi energy level pinning effect is a major cause which lead to contact barrier can not be modulated.In this article, through the use of atomic layer deposition(ALD), Between the Au metal and semiconductor GaSb deliberately insert a uniform layer of oxide interface layer, and study the different thickness of oxide film as the interface layer of Au/GaSb contact.According to the current-voltage of diode (I-V) characteristic curve which show different nonlinear impedance characteristics, calculated the barrier height and ideal factor of GaSb diode parameters, and the results are analyzed. The study finds that a certain thickness of oxide interface layer lead to the Fermi level depinning. And found that in theory any kind of the larger band gap and the smaller the dielectric constant insulation materials can be used to weaken the Fermi energy level pinning effect.