Improvement of Q rr-I DSS and dynamic avalanche of field-plate MOSFET by local lifetime control on the cathode side

Reducing the reverse recovery charge (Qrr) is effective for reducing switching loss in field plate (FP)-MOSFETs. A lifetime killer is utilized to reduce Qrr while increasing the leakage current in the off-state. Device simulation shows that a local lifetime killer on the cathode side successfully improves the trade-off between Qrr and IDSS in comparison with that of a uniform lifetime killer. A known issue of cathode lifetime killers is overshoot voltage by hard recovery. However, the overshoot voltage of FP-MOSFET decreases with a cathode lifetime killer owing to an internal snubber, which is a feature of FP-MOSFETs. An internal snubber with a large series resistance causes dynamic avalanche by both the increase of FP potential and excess carriers in high-speed operation. The cathode lifetime killer also improves dynamic avalanche by excess carriers. Consequently, the cathode lifetime killer is preferable for high-speed FP-MOSFETs.

Risk Factors for Relapse in Acute Bacterial Prostatitis: the Impact of Antibiotic Regimens

In the manuscript, we report a large series of acute bacterial prostatitis cases and describe data about the etiology, antibiotic resistance rate, and outcome, specially focused on the risk factors for relapse. We found high rates of resistance to the most frequently used antibiotics and a high relapse rate in patients whose treatment was not adjusted according to their microbiological susceptibility.

A new species of picture-winged flies of the genus Euphara Loew (Diptera, Ulidiidae)

Based on a large series of specimens found in several localities in Mexico Euphara loculata n. sp. is described. It is the second species of this Neotropical genus, and includes for the first time a description and illustration of the male and female genitalia of the genus.