New insights into the relation between channel hot carrier degradation and oxide breakdown short channel nMOSFETs

In this letter, we report new findings in the relation between channel hot-carrier (CHC) degradation and gate-oxide breakdown (BD) in short-channel nMOSFETS biased at V/sub G/>V/sub D/. We observe that the time-to-BD is strongly reduced in the hot carrier regime and that although the channel hot-electron injection into the oxide occurs mainly at the drain side, stress-induced leakage current (SILC) generation and oxide BD always occur at the source side. The results of these measurements indicate that not solely the energy of the injected electrons but also the oxide electric field is determinant in the oxide BD process.     

Particle Breakup in Shock Waves Studies by single Particle Light Scattering

The breakup of suspended, agglomerated submicron particles was studied by exposing the aerosol to weak shock waves of varying strength under conditions 400 ms^?1?v?880 ms^?1. A newly developed laser light-scattering diagnostic employing a top hat laser profile was used to size the particles passing through a very small scattering volume. By Comparing the optically measured particle size in front of and behind shock waves, the breakup of agglomerated particles could be clearly identified. The experiments indicate that the aerodynamic forces behind an incident shock overcome the particle binding force resulting in disintegration of the submicron agglomerates. The results are presented in form of a modified Weber number.     

L-Expressnet: The Communication Subnetwork for the C-NET Project

L-Expressnet is the communication suxbnetwork for the CNET local area network project of the CNR, Italy. Based on a single bus topology, it utilizes a simple and efficient virtual-token access protocol which provides ordered and collision-free transmission. The paper discusses the needs which led to L-Expressnet, describes the protocol, proves its correct operation, and compares its throughput-delay performance with those of other typical bus Protocols. A major advantage of L-Expressnet is that its implementation may be based on Ethernet standard transceivers and network interfaces.     

A family of highly symmetric codes

We define a class of codes admitting a large automorphism group. This family contains the binary extended Hamming code, the hexacode, the Golay codes, the Pless symmetry codes, as well as the [16,4,12]/sub 8/-codes constructed by Marcugini et al. A computer search resulted in the construction of codes with new parameters [28,7,18]/sub 8/,[32,8,20]/sub 8/, and [39,13,17]/sub 4/ belonging to this family.     

Electroluminescence spectroscopy for reliability investigations of 1.55 μm bulk semiconductor optical amplifier

This paper demonstrates the complementary relation between functional parameters and electroluminescence spectroscopy for reliability investigations of 1550 nm Semiconductor Optical Amplifiers of 700 μm length active region. Ageing tests have been set to 270 mA-100 °C-1500 h and realized on two different wafers showing more impact on wafer 1 than on wafer 2. Our investigations are particularly focused on interpretation of electroluminescence spectra, from reference and aged SOAs of wafer 1, leading to an improvement of degradation mechanisms understanding. The shift rate to lower energies of the recombination energy peak at 1550 nm, as reported by electroluminescence spectra between reference and aged SOAs in relation with the decrease of optical power measured at 200 mA for the degraded SOA and completed by I(V) characterizations, suggest occurrence of non radiative deep centers near the buried ridge structure in relation with the cleaning process uniformity of interfaces before epitaxial overgrowth. These defects mainly trap majority injected carriers instead of minority carriers reducing the luminescence in the active zone. By monitoring the most sensitive failure indicator (pseudo-threshold current), lifetime distributions are also calculated to determine failure rate, between 150 and 200 FITs over 15 years for operating conditions (25 °C-200 mA) using experimental degradation laws and statistic computations, demonstrating the overall robustness of this technology.     

A Narrowband Pulse-Echo Technique for In Vivo Ultrasonic Attenuation Estimation

The principles of a narrowband technique for pulse echo attenuation measurements are presented. Experiments are described which compare the attenuation in tissue-mimicking phantoms, measured by known methods, to the attenuation measured by the present technique. The effects of various experimental parameters on the results are investigated. The attenuation in spleens of canine models and in livers of human volunteers is presented.