An EKV-based high voltage MOSFET model with improved mobility and drift model

An EKV-based high voltage MOSFET model is presented. The intrinsic channel model is derived based on the charge based EKV-formalism. An improved mobility model is used for the modeling of the intrinsic channel to improve the DC characteristics. The model uses second order dependence on the gate bias and an extra parameter for the smoothening of the saturation voltage of the intrinsic drain. An improved drift model [Chauhan YS, Anghel C, Krummenacher F, Ionescu AM, Declercq M, Gillon R, et al. A highly scalable high voltage MOSFET model. In: IEEE European solid-state device research conference (ESSDERC), September 2006. p. 270–3; Chauhan YS, Anghel C, Krummenacher F, Maier C, Gillon R, Bakeroot B, et al. Scalable general high voltage MOSFET model including quasi-saturation and self-heating effect. Solid State Electron 2006;50(11–12):1801–13] is used for the modeling of the drift region, which gives smoother transition on output characteristics and also models well the quasi-saturation region of high voltage MOSFETs. First, the model is validated on the numerical device simulation of the VDMOS transistor and then, on the measured characteristics of the SOI-LDMOS transistor. The accuracy of the model is better than our previous model [Chauhan YS, Anghel C, Krummenacher F, Maier C, Gillon R, Bakeroot B, et al. Scalable general high voltage MOSFET model including quasi-saturation and self-heating effect. Solid State Electron 2006;50(11–12):1801–13] especially in the quasi-saturation region of output characteristics.     

A 65nm CMOS Ramp Generator Design and its Application Towards a BIST Implementation of the Reduced-Code Static Linearity Test Technique for Pipeline ADCs

This work presents an efficient on-chip ramp generator targeting to facilitate the deployment of Built-In Self-Test (BIST) techniques for ADC static linearity characterization. The proposed ramp generator is based on a fully-differential switched-capacitor integrator that is conveniently modified to produce a very small integration gain, such that the ramp step size is a small fraction of the LSB of the target ADC. The proposed ramp generator is employed in a servo-loop configuration to implement a BIST version of the reduced-code linearity test technique for pipeline ADCs, which drastically reduces the volume of test data and, thereby, the test time, as compared to the standard test based on a histogram. The demonstration of the pipeline ADC BIST is carried out based on a mixture of transistor-level and behavioral-level simulations that employ actual production test data.     

Current situation and control strategies for resurgence of diphtheria in newly independent states of the former Soviet Union

Since 1990, an epidemic of diphtheria has spread throughout the newly independent states of the former Soviet Union, and by 1995 a total of 47 808 cases were reported. During the early stages of the epidemic, adequate control measures were not taken and vaccine was in short supply; possible contributing factors to the spread of the epidemic are the presence of highly susceptible child and adult populations, socioeconomic instability, population movement, and a deteriorating health infrastructure. Although WHO views the epidemic as an International public-health emergency and, together with UNICEF and the International Red Cross, has formulated a strategy to combat the epidemic, the necessary funds have not been made fully available. Current vaccination recommendations also need to be reviewed to ensure that population immunity will be adequate to prevent any resurgence of diphtheria in Europe and North America.     

Efficient Implementations of Software Architectures via Partial Evaluation

The notion of flexibility (that is, the ability to adapt to changing requirements or execution contexts) is recognized as a key concern in structuring software, and many architectures have been designed to that effect. However, the corresponding implementations often come with performance and code size overheads. The source of inefficiency can be identified to be in the loose integration of components, because flexibility is often present not only at the design level but also in the implementation. To solve this flexibility vs. efficiency dilemma, we advocate the use of partial evaluation, which is an automated technique to produce efficient, specialized instances of generic programs. As supporting case studies, we consider several flexible mechanisms commonly found in software architectures: selective broadcast, pattern matching, interpreters, software layers, and generic libraries. Using Tempo, our specializer for C, we show how partial evaluation can safely optimize implementations of those mechanisms. Because this optimization is automatic, it preserves the original genericity and extensibility of the implementation.     

Monitoring pitting corrosion of AISI 316L austenitic stainless steel by acoustic emission technique: Choice of representative acoustic parameters

This experimental work was aimed at investigating the monitoring of pitting corrosion by the acoustic emission (AE) technique, for pits developed by potentiostatic or galvanostatic polarization on two types of 316L austenitic stainless steels, in a 3% NaCl solution acidified to pH 2. The study of the evolution of AE global activity during the test showed the existence of a time delay before pits became emissive. This time delay and the AE events number rate measured during the propagation step of the pits are closely correlated with the sensitivity of the material towards pitting and with the polarization procedure. Moreover, the evolution of cumulative % of AE signals number versus selected acoustic parameters shows that rise time and counts number of signals appear to be discriminating acoustic parameters for monitoring pitting corrosion of austenitic stainless steels by acoustic emission technique in our experimental conditions, whatever the polarization procedure and the type of tested steel.     

PRESSURE DROP AND HOMOGENIZATION EFFICIENCY OF A MOTIONLESS MIXER

Pressure drop and homogenization efficiency of a motionless mixer of helical type have been studied experimentally. For evaluation of the drag coefficient the equation has been proposed which is valid within the range of Reynolds number from 10^?2 to 10⁴ The efficiency of the motionless mixer for mixing of two Newtonian liquids has been investigated by using a decolourization method. For the operating conditions studied in this work it appears that there is the worse performance of the mixer about the Reynolds number of 50. No influence of volume flow rate ratios (from 1 to 10) upon the performance of the mixer has been observed. A higher number of mixing elements must be applied for homogemzation of liquids with viscosity ratios above 100 as compared with that for viscosity ratio 1.     

X-ray microbeam strain investigation on Cu-MEMS structures

The mechanical properties of simple metals in small dimensions have been the objects of many studies. Average stress measurements clearly show that yield stress increases significantly when the size decreases but local strain measurements indicate considerable grain-to-grain and intra-grain strain variations. The link between the macroscopic behaviour of microstructures and the corresponding local processes is still difficult to analyse.Copper is used in advanced microelectronic interconnects and the mechanical properties of narrow interconnects is a key issue for the reliability of devices. Average strain measurements performed on line arrays show a drastically different behaviour in narrow lines as compared with wide lines. ST microelectronics in Rousset developed a MEMS sensor integrated in the damascene process to follow the stress after processing. This microsystem can be a very efficient tool to monitor the average stress in interconnects on the chip. The gradient of strain in interconnects may lead to failures from void and hillocks and local stress repartition can be obtained through X-ray microdiffraction. Laue microdiffration is a unique non-destructive method to investigate the strain grain-by-grain in microstructures. The diffraction patterns were obtained at ESRF on BM32 beam line. We present the first steps of the investigation of a MEMS investigated by Laue microdiffraction. The sub-micron X-ray-beam allows a mapping of the microstructure with a step of around 1 μm, which is also the value of the estimated grain size. We present results on the orientation and stress at a sub-micron scale obtained from the Laue-diffraction measurements on the MEMS.