Electrical characteristics of Al/CeO2(200)/Si(100) and Al/CeO2(111)/Si(100) metal-insulator-semiconductor structure

Capacitance-voltage (C-V) and current-voltage (I-V) characteristics of Al/CeO3/Si(100) metal-insulator-semiconductor structures were found to he dependent on the crystal orientations of CeO2 thin films, which were deposited by radio-frequency magnetron sputtering. The C-V curve for the Al/CeO2/Si(100) structure made with CeO2 with (200)-preferred orientation (referred to as CeO2(200)) did not show any notable hysteresis, while the Al/CeO2/Si(100) structure made with CeO2 with (111)-preferred orientation (referred to as CeO2(111)) showed a counter-clockwise hysteresis. whose width was as high as similar to 1.5 V. The hysteresis difference between Al/CeO2(200)/Si(100) and Al/CeO2(111)/Si(100) is thought due to the difference in the preferred orientation of the CeO2 layer, and thus the stress between the CeO2 thin film and the Si substrate. The Al/CeO2(111)/Si(100) structure with CeO2 of larger grains showed larger leakage current than the Al/CeO2(200)/Si(100) structure with CeO2 of smaller grains.