Distribution and coverage of 40 nm gold nano-particles on aluminum and hafnium oxide using electrophoretic method and fabricated MOS structures

In this paper, electrophoretic method (EPD) is used to deposit 40 nm gold nano-particles (GNPs) on atomic layer deposited (ALD) grown oxides. Ultra-High Resolution Scanning Electron Microscopy (HRSEM) has been used to study the distribution of gold nano-particles on both Al2O3 and HfO2 thin films as a function of dipping time. The results show better distribution and mechanical adhesion of GNPs on top of HfO2 compared to Al2O3. Additionally, metal-oxide-semiconductor (MOS) structures with GNPs embedded within the HfO2 layers are fabricated. The distribution and coverage of the GNPs are analyzed using hysteresis loop of capacitance-voltage measurements at (1.0 MHz) and by quantifying the threshold voltage shift (Delta Vt). Moreover, the distribution of the GNPs as function of dipping time is discussed in terms of the measured Delta Vt. The results show an increase in Delta Vt with longer dipping time followed by a drop in the Delta Vt. Moreover, the Vt shift vs. dipping time indicates changes in the electrophoretic mobility behavior and the final distribution of GNPs on the surface of the HfO2. (C) 2016 Elsevier Ltd. All rights reserved.