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.

Reliability of 4H-SiC (0001) MOS Gate Oxide by NO Post-Oxide-Annealing

In this work, we investigated the oxide reliability of 4H-SiC (0001) MOS capacitors, the oxide was fabricated about 60 nm by thermal oxidation temperature at 1350°C, the oxides than annealed at different temperatures and times in diluted NO (10% in N2). The 4H-SiC MOS structure was analyzed by C-V and I-V measurement. Compared the J-E curves and Weibull distribution curves of charge-to-breakdown for fives samples under different annealing temperature and time, it shows that the high annealing temperature improves the electrical properties as the lifetime enhanced. The mode value of field-to-breakdown (EBD) for thermal oxides by post-oxide-annealing in NO for 30 min at 1350°C was 10.09 MV/cm, the charge-to-breakdown (QBD) of this sample was the highest in all samples, and the QBD value at 63.2% cumulative failure rate was 0.15 C/cm2. The QBD of the sample annealing at 1200°C for 120 min was 0.06 C/ cm2. The effects of NO annealing in high temperature enhance the lifetime of electrical properties and field-to-breakdown obviously. It can be demonstrated that the annealing temperature as high as 1300°C for 30 min can be used to accelerate TDDB of SiC MOS gate oxide.

Performance and Reliability Impacts of Extended Epitaxial Defects on 4H-SiC Power Devices

This work explores the effects of extended epitaxial defects on 4H-SiC power devices. Advanced defect mapping techniques were used on large quantities of power device wafers, and data was aggregated to correlate device electrical characteristics to defect content. 1200 V class Junction Barrier Schottky (JBS) diodes and MOSFETs were examined in this manner; higher voltage 3.3 kV class devices were examined as well. 3C inclusions and triangular defects, as well as heavily decorated substrate scratches, were found to be device killing defects. Other defects were found to have negligible impacts on device yield, even in the case of extremely high threading dislocation content. Defect impacts on device reliability was explored on MOS-gate structures, as well as long-term device blocking tests on both MOSFETs and JBS diodes. Devices that passed on-wafer electrical parametric tests were found to operate reliably in these tests, regardless of defect content.