OBIC analysis of stressed, thermally-isolated polysilicon resistors

High gain Optical Beam Induced Current (OBIC) imaging has been used for the first time to examine the internal structural effects of electrical stress on thermally-isolated polysilicon resistors. The resistors are examined over a wide range of current densities, producing Joule heating up to {approximately}1200{degrees}C. Throughout this current density range, the OBIC images indicate a clustering of dopant under dc stress and a more uniform distribution under ac conditions. The OBIC images also reveal areas that are precursors to catastrophic resistor failure. In addition to OBIC imaging, conventional electrical measurements were performed, examining the polysilicon resistance degradation and time-to-failure as a function of electrical stress. The electrical measurements show a monotonic increase in polysilicon resistor lifetime with frequency (up to 2 kHz) when subjected to a bipolar ac stress. The enhanced lifetime was observed even under high temperature (from Joule heating) stress conditions previously reported to be electromigration-free. The dopant redistribution indicated by the OBIC images is consistent with an electromigration stress experienced by the polysilicon resistors. The implications for thermally-isolated polysilicon resistor reliability are examined briefly

A Macroporous TiO2 Oxygen Sensor Fabricated Using Anodic Aluminium Oxide as an Etching Mask

An innovative fabrication method to produce a macroporous Si surface by employing an anodic aluminium oxide (AAO) nanopore array layer as an etching template is presented. Combining AAO with a reactive ion etching (RIE) processes, a homogeneous and macroporous silicon surface can be effectively configured by modulating AAO process parameters and alumina film thickness, thus hopefully replacing conventional photolithography and electrochemical etch methods. The hybrid process integration is considered fully CMOS compatible thanks to the low-temperature AAO and CMOS processes. The gas-sensing characteristics of 50 nm TiO2 nanofilms deposited on the macroporous surface are compared with those of conventional plain (or non-porous) nanofilms to verify reduced response noise and improved sensitivity as a result of their macroporosity. Our experimental results reveal that macroporous geometry of the TiO2 chemoresistive gas sensor demonstrates 2-fold higher (∼33%) improved sensitivity than a non-porous sensor at different levels of oxygen exposure. In addition, the macroporous device exhibits excellent discrimination capability and significantly lessened response noise at 500 °C. Experimental results indicate that the hybrid process of such miniature and macroporous devices are compatible as well as applicable to integrated next generation bio-chemical sensors

Combinatorial Study of Ni-Ti-Pt Ternary Metal Gate Electrodes on HfO\u3csub\u3e2\u3c/sub\u3e for the Advanced Gate Stack

The authors have fabricated combinatorial Ni–Ti–Pt ternary metal gate thin film libraries on HfO2 using magnetron co-sputtering to investigate flatband voltage shift (ΔVfb) , work function (Φm) , and leakage current density (JL) variations. A more negative ΔVfb is observed close to the Ti-rich corner than at the Ni- and Pt-rich corners, implying smaller Φm near the Ti-rich corners and higher Φm near the Ni- and Pt-rich corners. In addition, measured JL values can be explained consistently with the observed Φm variations. Combinatorial methodologies prove to be useful in surveying the large compositional space of ternary alloymetal gate electrode systems

Channel Hot-Electron Degradation On 60-Nm Hfo2-Gated Nmosfet Dc And Rf Performances

Channel hot-carrier-induced dc and RF performance degradations in 60-nm high-k nMOSFETs are examined experimentally. RF performances such as the cutoff frequency, noise figure, linearity, and flicker noise of high-k MOSFETs show significant vulnerability to the hot-electron effect. Analytical equations for normalized RF degradations relating to the device dc and ac parameters are derived. Good agreement between the analytical predictions and experimental data is obtained. The accuracy of the model equations suggests fast and effective evaluation of noise figure and linearity degradations using simple dc and ac parameters directly. © 2006 IEEE

Band offsets of Al2O3/InxGa1-xAs (x=0.53 and 0.75) and the effects of postdeposition annealing

Band offsets at the interfaces of InxGa1-xAs/Al2O3/Al where x=0.53 and 0.75 were determined by internal photoemission and spectroscopic ellipsometry. The photoemission energy threshold at the InxGa1-xAs/Al2O3 interface was found to be insensitive to the indium composition but shifted to a lower energy after a postdeposition annealing at high temperatures. Subthreshold electron photoemission was also observed for the annealed sample and was attributed to interfacial layer formation during the annealing process

A Tutorial Introduction to IoT Design and Prototyping with Examples

The dramatic drop in price of computing hardware, coupled with the recent breakthroughs in embedded systems design that enabled the integration of high‐level software and low‐level electronics, have created a paradigm shift in embedded systems development. This has led to the development of different varieties of user‐friendly Internet of Things (IoT) hardware development platforms for IoT prototyping. The ubiquity of such prototyping platforms has undoubtedly contributed toward the explosive growth of the IoT, which is already seeping into all areas of human endeavor, including transportation, logistics, business, and healthcare. Building IoT projects that can be controlled over the Internet can be challenging, especially for beginners. This chapter discusses the design and development of prototypes for IoT applications with focus on Arduino and Raspberry Pi platforms. The aim is to provide insightful information on best practices for designing and prototyping IoT projects, as well as to serve as step‐by‐step guidelines for beginners