Design of Low Power Less Leakage Quarternary Adder Using CMOS

In VLSI, design and implementation of circuits with MOS devices and binary logic are quite usual. The Main Objective is to design a low power and minimum leakage Quaternary adder. The VLSI field consists of Multi-valued logic (MVL) such as ternary and Quaternary Logic (QTL). The Failures such as Short Channel Effects (SCE) Impact-ionization and surface scattering are in normalized aspects. The Quaternary radix on MVL (multi-valued logic) monitors and reduces the area. The Quaternary (four-valued) logic converts the quaternary signals and binary signals produced by the by the existing binary circuits. The Proposed is carried out with LTSPICE tool and CMOS technology.

Fixed-charge generation in SiO2/GaN MOS structures by forming gas annealing and its suppression by controlling Ga-oxide interlayer growth

A recent study has shown that anomalous positive fixed charge is generated at SiO2/GaN interfaces by forming gas annealing (FGA). Here, we conducted systematic physical and electrical characterizations of GaN-based metal-oxide-semiconductor (MOS) structures to gain insight into the charge generation mechanism and to design optimal interface structures. A distinct correlation between the amount of FGA-induced fixed charge and interface oxide growth indicated the physical origins of the fixed charge to be defect formation driven by reduction of the Ga-oxide (GaOx) interlayer. This finding implies that, although post-deposition annealing in oxygen compensates for oxygen deficiencies and FGA passivates defect in GaN MOS structures, excessive interlayer GaOx growth leads to instability in the subsequent FGA treatment. On the basis of this knowledge, SiO2/GaOx/GaN MOS devices with improved electrical properties were fabricated by precisely controlling the interfacial oxide growth while taking advantage of defect passivation with FGA.

Optimized Technologies for Cointegration of MOS Transistor and Glucose Oxidase Enzyme on a Si-Wafer

The biosensors that work with field effect transistors as transducers and enzymes as bio-receptors are called ENFET devices. In the actual paper, a traditional MOS-FET transistor is cointegrated with a glucose oxidase enzyme, offering a glucose biosensor. The manufacturing process of the proposed ENFET is optimized in the second iteration. Above the MOS gate oxide, the enzymatic bioreceptor as the glucose oxidase is entrapped onto the nano-structured TiO2 compound. This paper proposes multiple details for cointegration between MOS devices with enzymatic biosensors. The Ti conversion into a nanostructured layer occurs by anodization. Two cross-linkers are experimentally studied for a better enzyme immobilization. The final part of the paper combines experimental data with analytical models and extracts the calibration curve of this ENFET transistor, prescribing at the same time a design methodology.

Status and Prospects of Cubic Silicon Carbide Power Electronics Device Technology

Wide bandgap (WBG) semiconductors are becoming more widely accepted for use in power electronics due to their superior electrical energy efficiencies and improved power densities. Although WBG cubic silicon carbide (3C-SiC) displays a modest bandgap compared to its commercial counterparts (4H-silicon carbide and gallium nitride), this material has excellent attributes as the WBG semiconductor of choice for low-resistance, reliable diode and MOS devices. At present the material remains firmly in the research domain due to numerous technological impediments that hamper its widespread adoption. The most obvious obstacle is defect-free 3C-SiC; presently, 3C-SiC bulk and heteroepitaxial (on-silicon) display high defect densities such as stacking faults and antiphase boundaries. Moreover, heteroepitaxy 3C-SiC-on-silicon means low temperature processing budgets are imposed upon the system (max. temperature limited to ~1400 °C) limiting selective doping realisation. This paper will give a brief overview of some of the scientific aspects associated with 3C-SiC processing technology in addition to focussing on the latest state of the art results. A particular focus will be placed upon key process steps such as Schottky and ohmic contacts, ion implantation and MOS processing including reliability. Finally, the paper will discuss some device prototypes (diodes and MOSFET) and draw conclusions around the prospects for 3C-SiC devices based upon the processing technology presented.

Linearization Technique of Low Power Opamps in CMOS FD-SOI Technologies

Negative feedback applied to the back gate of MOS devices available in FD-SOI (fully depleted silicon on insulator) CMOS technologies can be used to improve the linearity of operational amplifiers. Two operational amplifiers designed and fabricated in a 22 nm FD-SOI technology illustrate this technique, as well as its advantages and limitations.