In situ steam generation (ISSG) versus standard steam technology: impact on oxide reliability

This work studies the reliability behaviour of gate oxides grown by in situ steam generation technology. A comparison with standard steam oxides is performed, investigating interface and bulk properties. A reduced conduction at low fields and an improved reliability is found for ISSG oxide. The initial lower bulk trapping, but with similar degradation rate with respect to standard oxides, explains the improved reliability results.     

First full-scale demonstration of mercury control in Alberta

Alberta electricity companies, TransAlta, ATCO, and EPCOR, teamed with GE Energy to conduct full-scale evaluation of sorbent injection in Sundance Unit 5 operated by TransAlta. Sundance Unit 5 fires a Western Canadian sub-bituminous coal and is equipped with cold-side ESP for PM control. Goals of the program were to evaluate: (1) the ability of achieving 70% or greater mercury reduction using activated carbon injection in long-term tests (30 days), (2) the effect of sorbent injection on ESP performance and opacity in long-term testing, and (3) the effects of combustion conditions on “natural” mercury removal in fly ash.     

Tunnel oxide degradation under pulsed stress

A key issue for Flash cell scaling down is the reduction of tunnel oxide thickness limited by the higher gate leakage current (Stress Induced Leakage Current, SILC) after cycling. It is possible to reduce the oxide degradation during cycling by reducing the stress pulse duration and increase the time between pulses. This allows the annealing of precursor sites with an overall reduction of stable traps. Aim of this work is the investigation of the SILC induced by pulsed stress and the corresponding charge trapped in the oxide during stress. The impact of the oxidation technology will also be discussed.     

Short communication: Lymphoproliferative response to lipopolysaccharide and incidence of infections in periparturient dairy cows

This preliminary study aimed at assessing whether the in vitro proliferation of peripheral blood mononuclear cells in response to lipopolysaccharide permits individual characterization of periparturient dairy cows, and whether this parameter may be associated with incidence of infections and with some of the single nucleotide polymorphisms located on the toll-like receptor 4 (TLR4) gene. Based on the average response of peripheral blood mononuclear cells to lipopolysaccharide over 7 time points during the transition period, 31 cows were categorized as low (LO), medium (MED), and high (HI) responders. This categorization identified 7 HI, 19 MED, and 5 LO cows, respectively. Genomic DNA was genotyped for P-226 C>G and E3+2021 C>T TLR4 single nucleotide polymorphisms. Monitoring of the health status revealed that 8 of the 31 cows suffered from clinical mastitis, metritis, or interdigital dermatitis during the first 60 d in milk. The association study pointed out that none of the HI cows and all of the LO cows developed an infection; cows with the CCGT haplotype remained healthy and none of them belonged to the LO responder category.     

Impact of Contact Materials and Operating Conditions on Stability of Micromechanical Switches

Nano and micromechanical switches are of great interest in applications that require high speed, low-power consumption and high electrical isolation. There is strong evidence that airborne hydrocarbon accumulation on the contact surfaces of the switch is a key cause for device failure. Relatively unexplored contact materials such as RuO₂ are of interest because they are believed to be less prone to hydrocarbon deposit accumulation than more commonly used materials such as Pt and Au. Here, we measure the reliability of RuO₂ and Pt-coated microswitches in hydrocarbon-rich environments with N₂ and N₂:O₂ background gases. The RuO₂ material performs very poorly in contaminated N₂, but very well in contaminated N₂:O₂. Furthermore, RuO₂ performs much better than Pt in the contaminated N₂:O₂. It is demonstrated that the deposit, initially being an insulator, can be electrically broken-down, thereby substantially lowering switch resistance. It is further shown that the passage of electrical current through the contacts augments deposit accumulation.     

High-resolution electron microscopy of Zn- and Bi-related superlattices in ion implanted (1 0 0) Si

Nanosized precipitation in high-dose Zn⁺- and Bi⁺-implanted Si is investigated by high-resolution transmission electron microscopy of cross-sectional specimens. In spite of the different diffusivities of Zn and Bi in Si, their low solubility results in the precipitation of nanosized metallic inclusions revealed as superlattices composed of the host Si matrix and the implanted species.     

On the Performance of Chaos-Based Multicode DS-CDMA Systems

Multicode DS-CDMA systems assign more than one spreading sequence to each of the users. In these systems multiple access interference (MAI) is made of a synchronous and an asynchronous component. It is well known that asynchronous MAI alone can be minimized by means of chaos-based spreading. Here we address the trade-off between synchronous and asynchronous MAI by tuning the autocorrelation profile of the chaosbased spreading codes. Improvements in the number of users allowed in the system is demonstrated in certain load conditions with respect to the classical approach of providing each user with a set of orthogonal sequences taken from an i.i.d. process.