Progress Towards Arrays of Microcalorimeter X-Ray Detectors

2001 ◽  
Vol 7 (S2) ◽  
pp. 1050-1051 ◽  
Author(s):  
S.W. Nam ◽  
D.A. Wollman ◽  
Dale E. Newbury ◽  
G.C. Hilton ◽  
K.D. Irwin ◽  
...  
Keyword(s):  
Real Time ◽  
Energy Resolution ◽  
Count Rate ◽  
Small Area ◽  
High Performance ◽  
X Ray ◽  
Pixel Array ◽  
Primary Advantage ◽  
Low X ◽  
Single Pixel

The high performance of single-pixel microcalorimeter EDS (μ,cal EDS) has been shown to be very useful for a variety of microanalysis cases. The primary advantage of jxcal EDS over conventional EDS is the factor of 25 improvement in energy resolution (∽3 eV in real-time). This level of energy resolution is particularly important for applications such as nanoscale contaminant analysis where it is necessary to resolve peak overlaps at low x-ray energies. Because μcal EDS offers practical solutions to many microanalysis problems, several companies are proceeding with commercialization of single-pixel μal EDS technology. Two drawbacks limiting the application of uxal EDS are its low count rate (∽500 s−1) and small area (∽0.04 mm for a bare single pixel, ∽5 mm2 with a polycapillary optic). We are developing a 32x32 pixel array with a total area of 40 mm2 and with a total count rate between 105 s−1 and 106 s−1.

Use of Polycapillary Optics to Increase the Effective Area of Microcalorimeter Spectrometers

1997 ◽  
Vol 3 (S2) ◽  
pp. 1075-1076 ◽  
Author(s):  
D. A. Wollman ◽  
Christopher Jezewski ◽  
G. C. Hilton ◽  
Qi-Fan Xiao ◽  
K. D. Irwin ◽  
...  
Keyword(s):  
Energy Resolution ◽  
Count Rate ◽  
Small Area ◽  
Solid Angle ◽  
Collection Efficiency ◽  
High Energy ◽  
High Energy Resolution ◽  
X Rays ◽  
X Ray ◽  
Broad Energy Range

Although the performance of high-energy-resolution microcalorimeter spectrometers for x-ray microanalysis is encouraging, the future widespread acceptance of these spectrometers as valuable microanalysis instruments depends on improvements in both achievable count rate and geometrical x-ray collection efficiency. While the maximum output count rate of our microcalorimeter (∼160 s−1) is much less than that of conventional EDS detectors operating at their highest energy resolution (∼3000 s−1), we are confident that we can significantly improve the count rate without loss of energy resolution (∼10 eV FWHM over a broad energy range). Increasing the area (and thus solid angle) of the microcalorimeter is a more difficult problem, however, as the best microcalorimeter performance is achieved using small-area (typically 250 μm by 250 μm) absorbers with low heat capacity.This problem can be solved by using an x-ray lens to increase the collection efficiency of the microcalorimeter spectrometer. A polycapillary optic consisting of tens of thousands of fused capillaries can collect x-rays from a point x-ray source over a large solid angle and focus the x-rays onto the small-area absorber of the microcalorimeter.

scholarly journals Superconducting Tunnel Junction Array Development for High-Resolution Energy-Dispersive X-ray Spectroscopy

1998 ◽  
Vol 4 (6) ◽  
pp. 616-621 ◽  
Author(s):  
S. Friedrich ◽  
C.A. Mears ◽  
B. Nideröst ◽  
L.J. Hiller ◽  
M. Frank ◽  
...  
Keyword(s):  
Energy Resolution ◽  
Tunnel Junction ◽  
Count Rate ◽  
Energy Dispersive ◽  
Superconducting Tunnel Junction ◽  
X Rays ◽  
Detector Arrays ◽  
X Ray ◽  
Junction Array ◽  
Stj Detector

Cryogenic energy-dispersive X-ray detectors are being developed because of their superior energy resolution (10 eV FWHM for keV X-rays) compared to that achieved in semiconductor energy-dispersive spectrometry (EDS) systems. So far, their range of application is limited because of their comparably small size and low count rate. We present data on the development of superconducting tunnel junction (STJ) detector arrays to address both of these issues. A single STJ detector has a resolution of around 10 eV below 1 keV and can be operated at count rates of the order 10,000 counts/sec. We show that the simultaneous operation of several STJ detectors does not dimish their energy resolution significantly, and it increases the detector area and the maximum count rate by a factor given by the total number of independent channels.

scholarly journals High Energy Resolution X-Ray Spectrometer for High Count Rate Xrf Applications

1993 ◽  
Vol 37 ◽  
pp. 405-411
Author(s):  
C. S. Rossington ◽  
N. W. Madden ◽  
K. Chapman
Keyword(s):  
Energy Resolution ◽  
Count Rate ◽  
High Energy ◽  
Low Noise ◽  
High Energy Resolution ◽  
Photon Flux ◽  
Large Area ◽  
High Count ◽  
High Count Rate ◽  
X Ray

AbstractA new x-ray spectrometer has been constructed which incorporates a novel large area, low capacitance Si(Li) detector and a low noise JFET (junction field effect transistor) preamplifier. The spectrometer operates at high count Tates without the conventional compromise in energy resolution. For example, at an amplifier peaking time of 1 p.sec and a throughput count rate of 145,000 counts sec-1, the energy resolution at 5.9 keV is 220 eV FWHM. Commercially available spectrometers utilizing conventional geometry Si(Li) detectors with areas equivalent to the new detector have resolutions on the order of 540 eV under the same conditions. Conventional x-ray spectrometers offering high energy resolution must employ detectors with areas one-tenth the size of the new LBL detector (20 mm2 compared with 200 mm2). However, even with the use of the smaller area detectors, the energy resolution of a commercial system is typically limited to approximately 300 eV (again, at 1 μsec and 5.9 keV) due to the noise of the commercially available JFET's. The new large area detector is useful in high count rate applications, but is also useful in the detection of weak photon signals, in which it is desirable to subtend as large an angle of the available photon flux as possible, while still maintaining excellent energy resolution. X-ray fluorescence data from die new spectrometer is shown in comparison to a commercially available system in the analysis of a dilute muhi-element material, and also in conjunction with high count rate synchrotron EXAFS applications.

A Combined Scanning Electron Microscope/Electron Microprobe Analyzer

1968 ◽  
Vol 26 ◽  
pp. 368-369
Author(s):  
V.G. Macres ◽  
O. Preston ◽  
N.C. Yew ◽  
R. Buchanan
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Electron Microprobe ◽  
High Performance ◽  
Electron Gun ◽  
Objective Lens ◽  
Condenser Lens ◽  
X Ray ◽  
Low X ◽  
Scanning Electron

The instrument described here is the Materials Analysis Company Model 400S combined scanning electron microscope/electron micro-probe analyzer. It was designed specifically to incorporate the most advanced features of a high performance electron microprobe analyzer with those of a medium resolution (1000A°) scanning electron microscope. The high effective x-ray take-off angle of the instrument (38.5°) offers low x-ray absorption, and thus allows the analysis of fairly rough specimens. The large depth of focus of the scanned electron images further enhances the capability of examining rough specimens.The electron-optical column comprises a triode electron gun, double condenser lens and objective lens. The electron gun uses a conventional hairpin filament, autobiased Wehnelt cylinder and anode. An externally controlled filament/Wehnelt cylinder height adjustment is provided for optimizing gun performance at all operating potentials. The double condenser lens is unitized and has two lens regions and a common energizing coil.

A Digital Readout Scheme for Arrays of Microcalorimeter X-Ray Detectors

2000 ◽  
Vol 6 (S2) ◽  
pp. 742-743 ◽  
Author(s):  
S. Nam ◽  
D.A. Wollman ◽  
G.C. Hilton ◽  
J. Chervenak ◽  
S. Deiker ◽  
...  
Keyword(s):  
Room Temperature ◽  
Total Count ◽  
Digital Readout ◽  
X Ray ◽  
Pulse Processing ◽  
Pixel Array ◽  
Readout Scheme ◽  
Single Pixel ◽  
Shaping Amplifier ◽  
Squid System

While the performance of single-pixel microcalorimeter x-ray detectors has been shown to be very useful for microanalysis1, arrays of microcalorimeters will have a further impact on energy dispersive spectroscopy (EDS) by providing higher total count rates and larger effective areas. We are developing a system with a 32x32 pixel array with a total area of 40 mm2 and with a total count rate between 105 and 106 s-1. One of the challenges in constructing an array-based system will be the readout electronics.In a typical microcalorimeter EDS setup, shown in Fig. 1, the microcalorimeter is readout using a cryogenic amplifier (SQUID system) and analog feedback electronics to control the SQUID. The signal from the room-temperature SQUID electronics is either attached to a spectroscopy-grade shaping amplifier and MCA for real-time analog signal processing or attached to a digitizer for optimal pulse processing.

scholarly journals Pixel array detectors for high count rate X-ray imaging

2008 ◽  
Vol 64 (a1) ◽  
pp. C191-C192
Author(s):  
M.W. Tate ◽  
M. Hromalik ◽  
L.J. Koerner ◽  
H.T. Philipp ◽  
D.R. Schuette ◽  
...  
Keyword(s):  
Count Rate ◽  
High Count ◽  
High Count Rate ◽  
X Ray ◽  
Array Detectors ◽  
X Ray Imaging ◽  
Pixel Array

scholarly journals hv 2-concept breaks the photon-count limit of RIXS instrumentation

2020 ◽  
Vol 27 (5) ◽  
pp. 1235-1239 ◽  
Author(s):  
Ke-Jin Zhou ◽  
Satoshi Matsuyama ◽  
Vladimir N. Strocov
Keyword(s):  
Synchrotron Radiation ◽  
Energy Loss ◽  
Energy Resolution ◽  
Count Rate ◽  
Core Hole ◽  
X Ray ◽  
The Core ◽  
X Ray Scattering ◽  
Photon Count ◽  
Progressive Refinement

Upon progressive refinement of energy resolution, the conventional resonant inelastic X-ray scattering (RIXS) instrumentation reaches the limit where the bandwidth of incident photons becomes insufficient to deliver an acceptable photon-count rate. Here it is shown that RIXS spectra as a function of energy loss are essentially invariant to their integration over incident energies within the core-hole lifetime. This fact permits RIXS instrumentation based on the hv 2-concept to utilize incident synchrotron radiation over the whole core-hole lifetime window without any compromise on the much finer energy-loss resolution, thereby breaking the photon-count limit.

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