The effect of a post processing thermal anneal on pre-existing and stress induced electrically active defects in ultra-thin SiON dielectric layers

In this work we demonstrate the effects of a post processing high temperature anneal on the reliability of ultra-thin SiON layers fabricated into both nmos and pmos devices in terms of the initial gate leakage current, stress induced leakage current (SILC), and the time dependent dielectric breakdown behaviour. The devices under consideration were annealed at several temperatures up to 500 °C. We show that different mechanisms dominate the leakage behaviour at different temperatures by examining the relative leakage in the low voltage range. In particular for pmos devices, the emptying of electron traps induced by temperature and subsequent annealing of these traps alters the leakage current profiles significantly, dependent on anneal temperature. We show that annealing improves the time dependent dielectric breakdown (TDDB) lifetimes of nmos devices and examine the reasons for this.     

High-power high-Modulation-speed 1060-nm DBR lasers for Green-light emission

We report on the static and dynamic performance of high-power and high-modulation-speed 1060-nm distributed Bragg reflector (DBR) lasers for green-light emission by second-harmonic generation. Single-wavelength power of 387 mW at 1060-nm wavelength and green power as high as 99.5 mW were achieved. A thermally induced wavelength tuning of 2.4 nm and a carrier-induced wavelength tuning of -0.85 nm were obtained by injecting current into the DBR section. Measured rise-fall times of 0.2 ns for direct intensity modulation and 0.6 ns for wavelength modulation make the lasers suitable for >50-MHz green-light modulation applications.     

Determining the Dielectric Constants of Organic Photovoltaic Materials Using Impedance Spectroscopy

The photovoltaic and electrical properties of organic semiconductors are characterized by their low dielectric constant, which leads to the formation of polarons and Frenkel excitons. The low dielectric constant of organic semiconductors has been suggested to be significantly influential in geminate and bimolecular recombination losses in organic photovoltaics (OPVs). However, despite the critical attention that the dielectric constant has received in literature discussions, there has not yet been a thorough study of the dielectric constant in common organic semiconductors and how it changes when blended. In fact, there have been some inconsistent and contradictory reports on such dielectric constants, making it difficult to identify trends. Herein, at first a detailed explanation of a specific methodology to determine the dielectric constant in OPV materials with impedance spectroscopy is provided, including guidelines for possible experimental pitfalls. Using this methodology, the analysis for the dielectric constant of 17 common neat organic semiconductors is carried out. Furthermore, the relationship between the dielectric constant and blend morphology are studied and determined. It is found that the dielectric constant of a blend system can be very accurately predicted solely based on the dielectric constants of the neat materials, scaled by their respective weight ratios in the blend film.     

Space diversity in presence of discrete multipath fading channel

Most analytical studies of the performance of space diversity systems on fading channels assume a very rich multipath environment. In certain wireless applications, however, the number of significant multipath components can be small. In this letter, we consider a multipath channel in which the signal propagates from the transmitter to the receiver via L discrete paths which are uniformly distributed about the transmitter and receiver. For this channel, we study the effects of the number of multipath components and antenna array size on the error probability and outage capacity of space diversity systems. We observe that performance is significantly influenced by the presence of a channel with few multipath components.     

Surgical significance of extrahepatic biliary tree anomalies

A patient with an anomalous insertion of the right hepatic duct into the cystic duct was noted during cholecystectomy and confirmed by operative cholangiography. This case and related anomalies of the bile ducts are of sufficient importance that, because of the technical difficulties and dangers incidental to their presence, no surgeon who operates on the gallbladder and bile ducts can afford to be unaware of their existence. Adequate exposure, careful dissection, and accurate knowledge of the regional anatomy plus a realization of the frequency and multiplicity of abnormalities of the extrahepatic biliary tree are requisites for safe biliary tract surgery. In addition, carefully performed operative cholangiography can be an indispensable aid in the clarification of anatomic variations. In case of recognized operative injury to the extrahepatic biliary tree, primary repair or biliary-intestinal anastomosis can usually be carried out with good results.     

Genetic regulation of storaage protein content in maize endosperm

Sodium dodecylsulfate-polyacrylamide gel electrophoresis reveals that zein prepared from normal maize inbred (Zea mays L.) contains six separable components. Z1 and Z2 are the predominant species, with molecular weights of 21,800 and 19,000 daltons. Amino acid analysis of these two components shows that both are rich in glutamic acid, leucine, and proline, but low in lysine. Of the four minor bands, Z3, Z4, Z5, and Z6, the latter two exist only in trace amounts. A mutation at the opaque-2 locus severely suppresses the synthesis of Z1. The nonallelic mutant, opaque-7, strongly suppresses the synthesis of Z3 and Z4, while slightly reducing Z2. On the other hand, the floury-2 mutant appears to reduce the synthesis of these six proteins in the same relative proportion. In the double mutant combinations, opaque-2 apparently is epistatic to opaque-7 and floury-2 in the synthesis of zein components. The glutelin fraction shows a more complex banding pattern; however, qualitative differences are not apparent among the mutant lines examined.