986 research outputs found
An Initial study on The Reliability of Power Semiconductor Devices
An initial literature study combined with some basic comparative simulations has been performed on different electricfield modulation techniques and the subsequent reliability issues are reported for power semiconductor devices. An explanation of the most important power device metrics such as the offstate breakdown (BV) and specific on-resistance (RON) will be given, followed by a short overview of some of the electrostatic techniques (fieldplates, RESURF e.g. [1]) used to suppress peak electric fields. Furthermore it will be addressed that the high current operation of these devices results in shifting electric field peaks (Kirk effect [2], [3]) and as such different avalanche behavior, resulting in (gate oxide) reliability issues unlike those of conventional CMOS
Separation of random telegraph signals from 1/f noise in MOSFETs under constant and switched bias conditions
The low-frequency noise power spectrum of small dimension MOSFETs is dominated by Lorentzians arising from random telegraph signals (RTS). The low-frequency noise is observed to decrease when the devices are periodically switched 'off'. The technique of determining the statistical lifetimes and amplitudes of the RTS by fitting the signal level histogram of the time-domain record to two-Gaussian histograms has been reported in the literature. This procedure is then used for analysing the 'noisy' RTS along with the device background noise, which turned out to be 1/f noise. The 1/f noise of the device can then be separated from the RTS using this procedure. In this work, RTS observed in MOSFETs, under both constant and switched biased conditions, have been investigated in the time domain, Further, the 1/f noise in both the constant and the switched biased conditions is investigated
Moisture resistance of SU-8 and KMPR as structural material for integrated gaseous detectors
This paper treats the moisture resistance of SU-8 and KMPR, two photoresists considered as structural material in microsystems. Our experiments focus on the moisture resistance of newly developed radiation imaging detectors containing these resists. Since these microsystems will be used unpackaged, they are susceptible to all kinds of environmental conditions. Already after one day of exposure to a humid condition the structural integrity and adhesion of SU-8 structures, measured by a shear test is drastically reduced. KMPR photoresist shows much stronger moisture resistance properties, making it a suitable alternative in our application. © 2008 Elsevier Science. All rights reserved
Factors Associated with Bed-Sharing Within Racial Groups in a Sample of Mothers and Young Infants in Wisconsin
Since 2005, the American Academy of Pediatrics has recommended a separate but proximate sleep surface for infants (AAP, 2005). However, racial differences in the prevalence of bed-sharing and infant mortality (especially as a result of SIDS or unsafe sleep) continue. Limited research has examined predictors of bed-sharing by racial group, especially the AAP\u27s 2005 policy statement against it. The purpose of this study was to explore maternal-infant bed-sharing and infant sleep position for African-Americans and Whites in a sample of 2,530 respondents (822 African-American and 1,708 Whites) to the Wisconsin Pregnancy Risk Assessment and Monitoring System (PRAMS), a stratified sample of linked survey and birth certificate data between 2007 and 2010. Significantly more African-Americans (70.5%) reported bed-sharing than Whites (53.5%), z = 56.67, SEM = 0.005, p \u3c .001 (one-tailed). Factors associated with bed-sharing varied by race. In the final models, for African-Americans, a higher likelihood of bed-sharing was associated with ≥ 16 years of education (Odds Ratio[OR]: 2.540, 95% CI: 1.098-5.875), 13-15 years of education (OR: 1.924, 95% CI: 1.129-3.278), partner-related stress (OR: 1.859, 95% CI: 1.272-2.715), currently breastfeeding (OR: 1.598, 95% CI: 1.012-2.522), non-supine infant sleep (OR: 1.573, 95% CI: 1.077-2.297), and maternal age (OR: 0.963, 95% CI: 0.931-0.995). When Medicaid as method of payment was included, it reduced the likelihood of bed-sharing (OR: 0.550, 95% CI: 0.372-0.814). For Whites, bed-sharing was associated with currently breastfeeding (OR: 2.444, 95% CI: 1.939-3.081), income of 14,999 (OR: 1.833, 95% CI: 1.004-3.344), income of 49,999 (OR: 1.704, 95% CI: 1.234-2.351), being unmarried (OR: 1.667, 95% CI: 1.184-2.346), non-supine infant sleep (OR: 1.407, 95% CI: 1.069-1.852), and partner-related stress (OR: 1.381, 95% CI: 1.058-1.802). Needing money for food was also associated with bed-sharing (OR: 1.575, 95% CI: 1.158-2.143). Overall, subtle differences in the factors at play for African-American and White families who bed-share were demonstrated. Practice implications include culturally-relevant discussions and interventions. In-depth investigation of the family level context of bed-sharing, the ecology of infant sleep, and information received by families is suggested. These results help inform development of a targeted, culturally sensitive approach to educating families on sleep-related infant safety
Metal contacts to lowly doped Si and ultra thin SOI
We present our investigations on the fabrication of ohmic and Schottky contacts of several metals on lowly doped bulk Si and SOI wafers. Through this paper we evaluate the fabrication of rectifying devices in which no doping is intentionally introduced
Fabrication and characterization of the charge-plasma diode
We present a new lateral Schottky-based rectifier called the charge-plasma diode realized on ultrathin silicon-oninsulator. The device utilizes the workfunction difference between two metal contacts, palladium and erbium, and the silicon body. We demonstrate that the proposed device provides a low and constant reverse leakage-current density of about 1 fA/μm with ON/OFF current ratios of around 107 at 1-V forward bias and room temperature. In the forward mode, a current swing of 88 mV/dec is obtained, which is reduced to 68 mV/dec by back-gate biasing
Effect of Thermal Gradients on the Electromigration Lifetime in Power Electronics
The combined effects of electromigration and thermomigration are studied. Significantly shorter electromigration lifetimes are observed in the presence of a temperature gradient. This cannot be explained by thermomigration only, but is attributed to the effect of temperature gradient on electromigration-induced failures
- …