Characterization and calibration of a large area beta scintillation detector for determination of Sr-90

AbstractThe major aim of CMP is not the removal of excess material but the planarization of the surface. Therefore the determination of the planarization length appears to be more important than the removal rate itself. It has been shown, that the planarization length is not a constant process parameter, but is related to the removal respectively to the polish time in a square root behaviour. Founded on models proposed by Boning, Ouma, et. al. we applied a sequential polish on a single quasi infinite step. The resulting profile could be simulated by a sequential convolution of the surface contour with a Gaussian transfer function.To come closer to the situation on a chip pattern we investigated the planarization behaviour on a specific pattern of the MIT854AZ copper CMP test chip, where a large area of unpatterned surface touches a pattern with a specific constant density.The 200 mm wafer samples consisted of RIE structured oxide films covered with 850 nm ECD copper. The polish was performed on a standard semiconductor manufacturing tool, using a commercial consumables set. The surface profiles were determined by a high resolution profiler within the polishing sequence. The densely patterned areas are removed within a certain polishing time while the transition point between the unpatterned and patterned area appears as a global step. The deposited copper thickness is sufficient to study the contour evolution in both phases, before and after removal of the dense pattern. The paper presents the experimental results on the contour evolution for the patterned fields as well as the global step.

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A small, lightweight precordial counter for determination of cardiac output

Journal of Applied Physiology ◽

10.1152/jappl.1965.20.6.1365 ◽

1965 ◽

Vol 20 (6) ◽

pp. 1365-1366 ◽

Cited By ~ 1

Author(s):

Ralph J. Gorten

Keyword(s):

Cardiac Output ◽

Scintillation Detector ◽

Treadmill Exercise ◽

Bicycle Ergometer ◽

Indicator Dilution ◽

Energy Gamma ◽

Lead Shielding ◽

Thin Crystal ◽

Dilution Curves

A compact, lightweight scintillation detector which can be firmly attached to the anterior chest was fabricated in order to better adapt the isotope-precordial counting technic for measurements of cardiac output during exercise. In this manner useful indicator-dilution curves can be obtained without arterial puncture at light-to-heavy levels of bicycle ergometer or treadmill exercise. The use of a thin crystal and the omission of lead shielding and collimation of the detector is possible with a soft-energy gamma-emitting indicator of blood flow such as iodinated (I125) albumin. cardiac output during exercise; lightweight precordial scintillation detector; iodione 125; isotope-precordial counting technic Submitted on May 28, 1965

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Amadeus - a new type of large area scintillation detector with position-, energy- and time-of-flight determination

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/0168-9002(91)91110-h ◽

1991 ◽

Vol 310 (3) ◽

pp. 631-635 ◽

Cited By ~ 5

Author(s):

G. Anton ◽

J. Arends ◽

W. Beulertz ◽

J. Hey

Keyword(s):

Scintillation Detector ◽

Time Of Flight ◽

Large Area ◽

New Type

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Incorporation of satellite-derived snow-cover area in spatial snowmelt modeling for a large area: determination of a gridded degree-day factor

Annals of Glaciology ◽

10.3189/2013aog62a218 ◽

2013 ◽

Vol 54 (62) ◽

pp. 205-213 ◽

Cited By ~ 11

Author(s):

Yoshihiro Asaoka ◽

Yuji Kominami

Keyword(s):

Snow Cover ◽

Snow Water Equivalent ◽

Sensible Heat Flux ◽

Spatial Uncertainty ◽

Large Area ◽

Snow Cover Area ◽

Degree Day ◽

Snow Water ◽

Snowmelt Modeling

AbstractSpatial degree-day factors (DDFs) are required for spatial snowmelt modeling over large areas by the degree-day method. We propose a method to obtain DDFs by incorporating snow disappearance dates (SDDs), derived from 10 day composites of Satellite Pour l’Observation de la Terre (SPOT)/VEGETATION data, into the degree-day method. This approach allowed determination of DDFs for each gridpoint so as to better reflect regional characteristics than use of spatially constant DDFs obtained from point measurements. Simulations at six observation sites successfully accounted for variations in snow water equivalent (SWE), even at elevations different from the closest measurement site. These results suggest that incorporating satellite-derived SDDs into the degree-day method decreases spatial uncertainty compared with the use of spatially constant DDFs. Application of our method to Japanese cold regions revealed that gridded DDFs were negatively correlated with accumulated positive degree-days (APDDs) and were high only when APDDs were low. These results imply that high DDFs resulted from the dominant contribution of solar radiation to snowmelt at low temperatures and that low DDFs resulted from a relatively high contribution of sensible heat flux at high temperatures. The proposed method seems to adequately account for the main energetic components of snowmelt during the snow-cover season over large areas.

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Large Area Silicon Avalanche Photodiodes: Photomultiplier Tube Alternate

MRS Proceedings ◽

10.1557/proc-16-131 ◽

1982 ◽

Vol 16 ◽

Cited By ~ 13

Author(s):

G. Reiff ◽

M.R. Squillante ◽

H.B. Serreze ◽

G. Entine ◽

Gerald C. Huth

Keyword(s):

Scintillation Detector ◽

Gamma Spectroscopy ◽

Avalanche Photodiodes ◽

Low Noise ◽

Ease Of Use ◽

Active Area ◽

Large Area ◽

Device Structure ◽

Optical Sensitivity ◽

Large Active Area

ABSTRACTSilicon avalanche photodiodes have recently been shown to be a potential replacement for vacuum tube photomultipliers in many nuclear scintillation detector applications. The large active area, low noise, and ease of use of these solid-state photomultipliers makes them ideally suited to scintillation detector applications where overall size and ruggedness are a major concern. Historically, avalanche photodiodes have been limited for use in this capacity by small active areas, low internal gains, and poor optical sensitivity at the wavelengths at which most solid scintillator materials emit. Recent advances as the result of research aimed directly at the solution to these problems however, have successfully demonstrated one inch active area silicon avalanche photodiodes which produce a FWHM resolution of 9.5% for Cs137 at room temperature when coupled to a 1″ × 1″ NaI(Tl) scintillation crystal. Improvements to both material quality and device structure have advanced the state-of-the-art to make silicon avalanche photodiodes a viable alternative in scintillation gamma spectroscopy as well as for large area optical, beta, and low energy x-ray detectors.

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