The paper reviews our recent progress and current challenges in implementing advanced gate stacks composed of high-j dielectric materials and metal gates in mainstream Si CMOS technology. In particular, we address stacks of doped polySi gate electrodes on ultrathin layers of high-j dielectrics, dual-workfunction metal-gate technology, and fully silicided gates. Materials and device characteriza...

The dielectric breakdown property of ultrathin 2.5 and 5.0 nm hafnium oxide (HfO2) gate dielectric layers with metal nitride (TaN) gate electrodes for metal oxide semiconductor (MOS) structure has been investigated. Reliability studies were performed with constant voltage stressing to verify the processing condition effects (film thicknesses and post metal annealing temperatures) on times to br...

Fundamental limitations to oxide reliability are analyzed in silicon carbide based devices. A barrier height primarily determined by band offsets between metal/SiC and the dielectric, and the electric field in the dielectric results in tunneling current into the dielectric, resulting in its degradation. Since band offsets for SiC to most dielectrics are smaller than those with respect to Si, a ...

GaN field-effect transistors with impressive power switching characteristics have been demonstrated. Preventing their widespread field deployment are reliability and instability concerns. Some emanate from the use of a dielectric in the gate stack. Under typical operation, the gate dielectric comes periodically under intense electric field. This causes trapping and detrapping of electrons and i...

As the gate oxide thickness decreases below 2 nm, the gate leakage current increases dramatically due to direct tunneling current. This large gate leakage current will be an obstacle to reducing gate oxide thickness for the high speed operation of future devices. A MOS transistor with Ta2O5 gate dielectric is fabricated and characterized as a possible replacement for MOS transistors with ultra-...

The demands of future CMOS devices require a new gate dielectric material with higher dielectric constant than SiO2. Aluminum oxide is one of the high-k materials and an interesting candidate. Thin Al2O3 layers have been deposited by pulsed laser deposition (PLD) from a mono-crystalline sapphire target. This deposition technique was chosen because of its flexibility and availability. Aluminum o...

Principal goals in organic thin-film transistor (OTFT) gate dielectric research include achieving: (i) low gate leakage currents and good chemical/thermal stability, (ii) minimized interface trap state densities to maximize charge transport efficiency, (iii) compatibility with both pand nchannel organic semiconductors, (iv) enhanced capacitance to lower OTFT operating voltages, and (v) efficien...

Recently, AlN plasma-enhanced atomic layer deposition (ALD) passivation technique had been proposed and investigated for suppressing the dynamic on-resistance degradation behavior of high-electron-mobility transistors (HEMTs). In this paper, a novel gate dielectric and passivation technique for GaN-on-Si AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors (MISHEMTs) is pr...

Solution-processed gate dielectrics were fabricated with the combined ZrO2 and Al2O3 (ZAO) in the form of mixed and stacked types for oxide thin film transistors (TFTs). ZAO thin films prepared with double coatings for solid gate dielectrics were characterized by analytical tools. For the first time, the capacitance of the oxide semiconductor was extracted from the capacitance-voltage propertie...