Reliability testing of three-stage, low-noise PM (pseudomorphic) HEMT (high-electron-mobility transistor) MMICs (monolithic microwave integrated circuits) was performed with constant stress accelerated life tests at three temperatures. The reliability of PM HEMT MMICs was found to be as excellent as that of discrete HEMTs. The MTF is 2*10/sup 6/ h at a 125 degrees C channel temperature. This result is based on the failure criteria of noise figure and gain change of 0.5 and 1.0 dB, respectively, at 26.5 GHz. From the observed activation energy of 1.3 eV and the gate voltage shift, the failure mechanism was probably due to a combination of gate-sinking and oxygen diffusion into the active channel region of unpassivated HEMTs.< >
To improve the stability of multilayer graphene (MLG) doped with molybdenum pentachloride (MoCl 5 ) for low-resistance interconnects, we have newly developed an in-situ passivation process with molybdenum oxides. The improved air stability of dopants was confirmed with Raman spectroscopy by the direct MoO x passivation at room temperature.
Abstract 2D van der Waals (vdW) transition metal di‐chalcogenides (TMDs) have garnered significant attention in the nonvolatile memory field for their tunable electrical properties, scalability, and potential for phase engineering. However, their complex switching mechanism and complicated fabrication methods pose challenges for mass production. Sputtering is a promising technique for large‐area 2D vdW TMD fabrication, but the high melting point (typically T m > 1000 °C) of TMDs requires elevated temperatures for good crystallinity. This study focuses on the low‐ T m 2D vdW TM tetra‐chalcogenides and identifies NbTe 4 as a promising candidate with an ultra‐low T m of around 447 °C (onset temperature). As‐grown NbTe 4 forms an amorphous phase upon deposition that can be crystallized by annealing at temperatures above 272 °C. The simultaneous presence of a low T m and a high crystallization temperature T c can resolve important issues facing current phase‐change memory compounds, such as high Reset energies and poor thermal stability of the amorphous phase. Therefore, NbTe 4 holds great promise as a potential solution to these issues.
To evaluate the effects of low-dose intravitreal injections of bevacizumab (IVB) in retinopathy of prematurity (ROP). A total of 14 eyes of 7 patients received IVB (0.25mg/eye) for treatment of ROP from April 2011 to June 2012 at Showa University. This retrospective case series included the patients who were followed up for at least 5 months after IVB. Ten eyes of five patients were included in the analysis. The mean gestational age and birth weight were 24.6 (range: 22-26) weeks and 770 grams (range: 505-1055), respectively. Eight eyes of four patients with stage 3 ROP with plus disease were laser treated, and two eyes of one patient were treated with aggressive posterior ROP (AP-ROP) without laser use. All of the eyes received only a single injection of IVB. The mean injection age and body weight were 37.2 (range: 34-39) weeks of postconceptional age and 2073 grams (range: 1400-2995). Of the eight eyes with stage 3 ROP with plus disease, six eyes (four patients) regressed after IVB treatment. Two eyes (two patients) were treated with vitrectomy after IVB. The AP-ROP regressed after IVB and a subsequent laser treatment. IVB was performed as a salvage therapy, and low-dose IVB was effective for promoting the regression of ROP. However, IVB increased fibrotic traction in some eyes. In the BEAT-ROP study, a dosage of 0.625mg IVB was used as a monotherapy; however, intravitreally injected bevacizumab can escape to the systemic circulation. Thus, the use of a lower dosage of IVB for ROP in combination with laser therapy appears to be efficacious until the optimal dosage can be established.
A two-temperature RF-stressed accelerated life test on discrete pseudomorphic InGaAs power HEMT devices at 60 GHz shows a failure mode with an activation energy of 1.6 eV. The projected mean time-to-failure of 1 E7 hours at 125/spl deg/C channel temperature indicates that this device technology can be highly reliable for critical applications at millimeter-wave-frequencies.< >
