Studies on ZnO/Si heterojunction diode grown by atomic layer deposition technique

Abstract

In this paper studies on Si/ZnO heterojunction diode is presented. In this work Zinc oxide (ZnO) was conformally deposited on Silicon (Si) Wafer by atomic layer deposition (ALD) technique without using a buffer layer. For low-temperature ALD deposition, diethyl zinc (DEZn) and deionized (DI) water were used as the sources for zinc and oxygen respectively. Surface characterization and optical characterization are done to show the quality of as-grown ZnO film. On top and bottom of the structure titanium/aluminium and aluminium were deposited respectively to get large area ohmic contacts. The junction properties are evaluated by measuring current-voltage (I-V) and capacitance-voltage (C-V) characteristics. I-V characteristics exhibited well defined rectifying behavior with a rectification ratio of 127 and turn-on voltage of 0.6 V. The ideality factor of 2.72 and barrier height of 0.766 eV are showing the superior quality of the ZnO/Si heterojunction diode without a buffer layer. © 2013 American Scientific Publishers.