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Silicon pore optics are a new type of high-performance x-ray optics designed to enable future space-borne x-ray observatories such as European Space Agency's Athena. These optics will make it possible to build telescopes with effective areas of the order of a few square meters and angular resolutions better than 5 s of arc. During manufacturing of the optics, thin film metallic coatings are sputtered onto mirror plates to help achieve this large effective area. Then, these plates are stacked on top of each other using direct silicon bonding to achieve the shape of an approximate Wolter type-I telescope design. It is, therefore, necessary to verify the compatibility of the coating and bonding processes. We observe the unintentional removal of coatings on silicon pore optics plates after their wet chemical activation, a step required to make direct bonding possible. In this paper, we investigate plasma etching prior to thin film deposition as a solution to this problem. First, we ensure that plasma etching does not impact the low surface roughness required to achieve high imaging performance. Then, we demonstrate that plasma etching before thin film deposition prevents unintentional removal of the metallic coatings during the activation step, making coating deposition compatible with direct bonding of silicon pore optics plates. [ABSTRACT FROM AUTHOR]

Reported herein is development of a quadrupole mass spectrometer controller (MSC) with integrated radio frequency (rf) power supply and mass spectrometer drive electronics. Advances have been made in terms of the physical size and power consumption of the MSC, while simultaneously making improvements in frequency stability, total harmonic distortion, and spectral purity. The rf power supply portion of the MSC is based on a series-resonant LC tank, where the capacitive load is the mass spectrometer itself, and the inductor is a solenoid or toroid, with various core materials. The MSC drive electronics is based on a field programmable gate array (FPGA), with serial peripheral interface for analog-to-digital and digital-to-analog converter support, and RS232/RS422 communications interfaces. The MSC offers spectral quality comparable to, or exceeding, that of conventional rf power supplies used in commercially available mass spectrometers; and as well an inherent flexibility, via the FPGA implementation, for a variety of tasks that includes proportional-integral derivative closed-loop feedback and control of rf, rf amplitude, and mass spectrometer sensitivity. Also provided are dc offsets and resonant dipole excitation for mass selective accumulation in applications involving quadrupole ion traps; rf phase locking and phase shifting for external loading of a quadrupole ion trap; and multichannel scaling of acquired mass spectra. The functionality of the MSC is task specific, and is easily modified by simply loading FPGA registers or reprogramming FPGA firmware. [ABSTRACT FROM AUTHOR]