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Abstract: The recently reported cross-section data for the production of 82Sr via the natRb(p,xn)82Sr process were evaluated. For the natRb(p,xn)85Sr process, cross-sections were measured experimentally over the proton energy range of 25–45MeV, a region where very few data existed. An evaluation of the recently published data on the formation of 85Sr was then also performed. From the recommended data curves, the integral yields of the desired radionuclide 82Sr and the impurity 85Sr were calculated. Yields were also determined experimentally over several energy ranges using thick natRbCl targets. The experimental and calculated yields were found to be in agreement within 15%. These integral tests add confidence to the evaluated cross-section data. For the production of 82Sr, an incident proton energy of 60MeV or above is recommended; the 85Sr impurity then corresponds to <20%. [Copyright &y& Elsevier]

Abstract: We examine the effects of device scaling in both vertical and lateral dimensions for the metamorphic high electron mobility transistors (MHEMTs) on the DC and millimeter-wave electrical performances by using a hydrodynamic transport model. The well-calibrated hydrodynamic simulation for the sub-0.1-μm offset Γ-gate In0.53Ga0.47As/In0.52Al0.48As MHEMTs shows a reasonable agreement with the electrical characteristics measured from the fabricated 0.1μm devices. We have calibrated all the parameters using the measurement data with various physical considerations to take into account the sophisticated carrier transport physics in sub-0.1-μm devices. Being simulated with these calibrated parameters, the optimum device performance is obtained at a source-drain spacing of 2μm, a gate length of 0.05μm, a barrier thickness of 10nm and a channel thickness of 12nm. [Copyright &y& Elsevier]

Abstract: Spatial resolution of two types of graded-gap Al x Ga1− x As X-ray detectors, p+-Al x Ga1− x As layer (A type) and p-Al x Ga1− x As −p+-GaAs–p-Al x Ga1− x As structure (B-type), is investigated. Two processes, the diffusion of generated charge and broadening of light beam, cause blurring of X-ray image in the detectors. Optical broadening of light beam was eliminated in B-type structure. The value of spatial resolution mainly depends on the thickness of graded-gap Al x Ga1− x As layer. Spatial resolution of 10LP/mm for the A-type structure of 50μm thickness and 25LP/mm for B-type structure of 18μm thickness was experimentally observed. [Copyright &y& Elsevier]

Abstract: Ferromagnetic amorphous Ni16Fe62Si8B14 layer have been studied as free layers for magnetic tunnel junctions (MTJs) to enhance cell switching performance. Traditional MTJ free layer materials such as NiFe and CoFe were also prepared for switching comparison purposes. Both NiFeSiB and NiFe resulted in an order of magnitude smaller switching fields compared to the CoFe. The switching field was further reduced for the synthetic antiferromagnetic NiFeSiB free layered structure. [Copyright &y& Elsevier]