Electrical characteristics analyses of zinc-oxide based MIS structure grown by atomic layer deposition

The ZnO films are grown on the p-type Si for metal-insulator-semiconductor (MIS) type Schottky barrier diode (SBHS) fabrication by atomic layer deposition (ALD) method. The electrical characteristics of the three diodes called as D1, D2 and D3 have been investigated. The surface characteristics and thin film in structure were detected by secondary ion mass spectrometry (SIMS) and atomic force microscopy (AFM). The current-voltage (I-V) properties of Al/ZnO/p-Si structures were analyzed in the dark at room temperature. The electrical specifications such as, barrier height (φb) ideality factor (n) and series resistance (Rs) of these structures were examined by Norde's function, Cheung method and thermionic emission (TE) theory. Barrier height values computed from Cheung and I-V method was found to be different from each other. Interface state density (Dit) of these structures was studied using the I-V properties. The non-ideal behavior of measured characteristics advised the presence of interface conditions. The acquired results imply that the fabricated diodes can be used for NIR Schottky photo detector applications.