Fabrication and characterization of AlN metal–insulator–semiconductor grown Si substrate

An experimental investigation was conducted to explore the effect of inserting a single AlGaN interlayer between AlN epilayer and GaN/AlN heterostructures on Si (111) grown by molecular beam epitaxy (MBE). It is confirmed from the scanning electron microscopy (SEM) that the AlGaN interlayer has a remarkable effect on reducing the tensile stress and dislocation density in AlN top layer. Capacitance–voltage (C–V) measurements were conducted to study the electrical properties of AlN/GaN heterostructures. While deriving the findings through the calculation it is suggested that the AlGaN interlayer can significantly reduce the value of effective oxide charge density and total effective number of charges per unit area which are [Formula: see text] and [Formula: see text], respectively.

Post-Deposition Annealing in Nitrous Oxide Ambient of RF-Magnetron Sputtered Y2O3 Film on Silicon Substrate

In this work, effects of post-deposition annealing (PDA) time (15, 30, and 45 min) in nitrous oxide ambient on Y2O3 film deposited on Si substrate using RF-magnetron sputtering have been systematically studied. Y2O3/Si system subjected to PDA time at 15 and 30 min has demonstrated a negative flatband voltage shift but a change to positive flatband voltage shift was observed when PDA time was prolonged to 45 min. The shift from negative to positive flatband voltage with enhancement of PDA time could be related to the accumulation of nitrogen in the Y2O3 gate that acted as negatively trap charge. It was perceived that sample subjected to PDA time at 30 min has demonstrated the best leakage current density-breakdown voltage (J-VB) characteristic. A correlation between the J-VB characteristics with effective oxide charge, slow trap density, interface trap density, and total interface trap density has been discussed.

Effects of Post-Deposition Annealing on CeO2 Gate Prepared by Metal-Organic Decomposition (MOD) Method on 4H-SiC

Electrical properties of MOD-derived CeO2 film deposited on n-type 4H-SiC have been investigated. Post-deposition annealing of the oxide was performed in argon ambient for 15 minutes at 600, 800, and 1000°C in order to optimize the oxide properties. Spin-on coating was then used to deposit the annealed oxide onto the substrate. Results indicated that the effective oxide charge and slow trap density increased as temperature increased. Negative effective oxide charges were revealed in all annealed oxides. The lowest leakage current and interface trap density was obtained in the sample annealed in the highest temperature.

Effect of Post Deposition Annealing on the Characteristics of Sol-Gel Derived HfO2 on 4H-SiC

The effects of post deposition annealing in forming gas (5 % H2 in 95 % N2) ambient at different temperatures (850, 950, and 1050 oC) on metal-oxide-semiconductor characteristics of sol-gel derived HfO2 gate on n-type 4H-SiC have been investigated. After 30 min of the annealing, an accumulation of positive effective oxide charge (Qeff) has been observed in all samples. The total interface trap density and Qeff of the oxides annealed at 850 and 950 oC are comparable but an increment and reduction of the respective densities have been recorded when the oxide was annealed at 1050 oC. A reduction of near interface trap density has been revealed as the annealing temperature has been increased. These observation was closely related to the increment of leakage current density as the annealing temperature increased.

Optimization of 4H-SiC MOS Properties with Cesium Implantation

The effect of incorporation of cesium with implantation on the electrical characteristics of SiO2/4H-SiC interface has been evaluated using MOS capacitors. With a cesium dosage of 1012 and 3x1012 cm-2 on deposited oxide re-oxidized in steam, effective oxide charge densities of - 1.4x1012 and -7.5x1011 cm-2 respectively were extracted and a cesium implant activation percentage of 33% was estimated from flatband voltage shift. Also, corresponding interfacial state densities of 2.5x1013 and 1.8x1013 cm-2-eV-1 near the conduction band edge were extracted from High-Low frequency C-V technique, showing a decreasing Dit with increasing Cs dosage.

Influence of Hydrogen Plasma Treatment Upon Native Oxides Plasma Grown on INP

Investigations of plasma grown native oxides on indium phosphide carried out recently [1,2] have shown that these oxides exhibit properties which are promising to be used in MIS structures on InP, due to their stable composition which includes [InxPyOz]n polyphosphate phase mainly and due to reduced density of interface states (Nss<1011 eV−1 cm−2). It has been shown also that MIS structures with plasma native oxides exhibit C-V characteristics shifted towards positive values of voltage bias. The flat band shift is assigned to a negative charge injected into oxide film during plasma oxidation. The presence of this negative charge in plasma grown native oxides on InP may cause instability of electric properties of MIS structures [2].The aim of this work was to make an attempt to influence upon negative effective oxide charge density by means of hydrogen plasma treatment.

Features of Plasma Grown Native Oxides on Indium Phosphide

ABSTRACTEllipsometry and XPS investigations of RF plasma grown native oxide and C-V measurements of its interface were performed.Strong dependence of the composition of the plasma grown native oxides and electric properties of MIS structures on the time of plasma treatment has been observed. The greater the content of stable polyphosphate phase of [InxPyOz] is in the native oxide composition, the better parameters of its interface with InP (NS 11 cm−2 eV−1 and the hysteresis of C-V characteristics≤0.2 V) and the lesser C-V drift after treatment may be achieved. Plasma oxidation results in creating a negative effective oxide charge density.