OPTICAL CHARACTERIZATION OF THE CARRIER DISTRIBUTION IN SILICON POWER DEVICES WITH DEFINED SPATIAL RESOLUTION

Measured one-dimensional static recombination radiation intensity distributions of P+NN+ structures are compared to p. n products yielded from a mathematical model. It is shown that the modelled data under correction for spatial resolution of the apparatus are in good qualitative agreement with measured data even in highly doped emitter regions

THE CURRENT STATUS OF POWER SEMICONDUCTORS

Trends in the design and technology of power semiconductor devices are discussed on the threshold of the year 2015. Well established silicon technologies continue to occupy the most of applications thanks to the maturity of switches like MOSFET, IGBT, IGCT and PCT. Silicon carbide (SiC) and gallium nitride (GaN) are striving to take over that of the silicon. The most relevant SiC device is the MPS (JBS) diode, followed by MOSFET and JFET. GaN devices are represented by lateral HEMT. While the long term reliability of silicon devices is well trusted, the SiC MOSFETs and GaN HEMTs are struggling to achieve a similar confidence. Two order higher cost of SiC equivalent functional performance at device level limits their application to specific cases, but their number is growing. Next five years will therefore see the co-existence of these technologies. Silicon will continue to occupy the most of applications and dominate the high-power sector. The wide bandgap devices will expand mainly in the 600 - 1200 V range and dominate the research regardless of the voltage class

Unsupervised Object Localization: Observing the Background to Discover Objects

Recent advances in self-supervised visual representation learning have paved the way for unsupervised methods tackling tasks such as object discovery and instance segmentation. However, discovering objects in an image with no supervision is a very hard task; what are the desired objects, when to separate them into parts, how many are there, and of what classes? The answers to these questions depend on the tasks and datasets of evaluation. In this work, we take a different approach and propose to look for the background instead. This way, the salient objects emerge as a by-product without any strong assumption on what an object should be. We propose FOUND, a simple model made of a single $conv1\times1$ initialized with coarse background masks extracted from self-supervised patch-based representations. After fast training and refining these seed masks, the model reaches state-of-the-art results on unsupervised saliency detection and object discovery benchmarks. Moreover, we show that our approach yields good results in the unsupervised semantic segmentation retrieval task. The code to reproduce our results is available at https://github.com/valeoai/FOUND.Comment: CVPR 202

4.5 kV Bi-mode Gate Commutated Thyristor design with High Power Technology and shallow diode-anode

The Bi-mode Gate Commutated Thyristor (BGCT) is a reverse conducting Gate Commutated Thyristor (GCT) where the diode regions are intertwined with GCT parts. In this work we examine the impact of shallow diode-anodes on the operation of the GCT and propose the introduction of optimised High Power Technology (HPT+) in the GCT part. In order to assess and compare the new designs with the conventional, a multi-cell mixed mode model for large area device modelling was used. The analysis of the simulation results show that the shallow diode does not affect the MCC whereas the introduction of the HPT+ allows for a step improvement

New Bi-Mode Gate-Commutated Thyristor Design Concept for High-Current Controllability and Low ON-State Voltage Drop

© 2016 IEEE. A new design approach for bi-mode gatecommutated thyristors (BGCTs) is proposed for high-current controllability and low ON-state voltage drop. Using a complex multi-cell mixed-mode simulation model which can capture the maximum controllable current (MCC) of large area devices, a failure analysis was performed to demonstrate that the new design concept can increase the MCC by about 27% at room temperature and by about 17% at 400 K while minimizing the ON-state voltage drop. The simulations depict that the improvement comes from the new approach to terminate the GCT part in the BGCT way of intertwining GCT and diode regions for reverse conducting operation

The Stripe Fortified GCT:A new GCT design for maximizing the controllable current

In this paper we introduce a new GCT design, namely the Stripe Fortified GCT, for the purpose of maximizing the controllable current by optimizing the current flow path in the device during turn-off. The main design of the new device along with variants are introduced. The MCC performance of this novel structure is assessed with a developed two dimensional model for full wafer simulations. Our results show that this new design is a very good candidate for increasing the MCC to values more than 5000A

A phase IIa, nonrandomized study of radium-223 dichloride in advanced breast cancer patients with bone-dominant disease

Radium-223 dichloride (radium-223) mimics calcium and emits high-energy, short-range alpha-particles resulting in an antitumor effect on bone metastases. This open-label, phase IIa nonrandomized study investigated safety and short-term efficacy of radium-223 in breast cancer patients with bone-dominant disease. Twenty-three advanced breast cancer patients with progressive bone-dominant disease, and no longer candidates for further endocrine therapy, were to receive radium-223 (50 kBq/kg IV) every 4 weeks for 4 cycles. The coprimary end points were change in urinary N-telopeptide of type 1 (uNTX-1) and serum bone alkaline phosphatase (bALP) after 16 weeks of treatment. Exploratory end points included sequential 18F-fluorodeoxyglucose positron emission tomography and computed tomography (FDG PET/CT) to assess metabolic changes in osteoblastic bone metastases. Safety data were collected for all patients. Radium-223 significantly reduced uNTX-1 and bALP from baseline to end of treatment. Median uNTX-1 change was −10.1 nmol bone collagen equivalents/mmol creatinine (−32.8 %; P = 0.0124); median bALP change was −16.7 ng/mL (−42.0 %; P = 0.0045). Twenty of twenty-three patients had FDG PET/CT identifying 155 hypermetabolic osteoblastic bone lesions at baseline: 50 lesions showed metabolic decrease (≥25 % reduction of maximum standardized uptake value from baseline) after 2 radium-223 injections [32.3 % metabolic response rate (mRR) at week 9], persisting after the treatment period (41.5 % mRR at week 17). Radium-223 was safe and well tolerated. Radium-223 targets areas of increased bone metabolism and shows biological activity in advanced breast cancer patients with bone-dominant disease

Tarantula Toxins Interact with Voltage Sensors within Lipid Membranes

Voltage-activated ion channels are essential for electrical signaling, yet the mechanism of voltage sensing remains under intense investigation. The voltage-sensor paddle is a crucial structural motif in voltage-activated potassium (Kv) channels that has been proposed to move at the protein–lipid interface in response to changes in membrane voltage. Here we explore whether tarantula toxins like hanatoxin and SGTx1 inhibit Kv channels by interacting with paddle motifs within the membrane. We find that these toxins can partition into membranes under physiologically relevant conditions, but that the toxin–membrane interaction is not sufficient to inhibit Kv channels. From mutagenesis studies we identify regions of the toxin involved in binding to the paddle motif, and those important for interacting with membranes. Modification of membranes with sphingomyelinase D dramatically alters the stability of the toxin–channel complex, suggesting that tarantula toxins interact with paddle motifs within the membrane and that they are sensitive detectors of lipid–channel interactions