Validation of TOPAS MC for modelling the efficiency of an extended-range coaxial p-type HPGe detector

Uncertainty propagation to the γ-γ coincidence-summing correction factor from the covariances of the nuclear data and detection efficiencies have been formulated. The method was applied in the uncertainty analysis of the coincidence-summing correction factors in the γ-ray spectrometry of the 134Cs point source using a p-type coaxial HPGe detector.

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Optimization of p-type HPGe detector model using Monte Carlo simulation

Journal of Radioanalytical and Nuclear Chemistry ◽

10.1007/s10967-020-07473-2 ◽

2020 ◽

Author(s):

Le Thi Ngoc Trang ◽

Huynh Dinh Chuong ◽

Tran Thien Thanh

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Hpge Detector ◽

P Type ◽

Detector Model

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Verification of physical parameters of insity p-type HPGe detector by scan method using collimated low energy photon beam and MNCP simulation

Applied Radiation and Isotopes ◽

10.1016/j.apradiso.2020.109229 ◽

2020 ◽

Vol 163 ◽

pp. 109229

Author(s):

Vu Ngoc Ba ◽

Le thi Ha Giang ◽

Bui Ngoc Thien ◽

Truong Thi Hong Loan ◽

Ngo Quang Huy

Keyword(s):

Hpge Detector ◽

Low Energy ◽

Photon Beam ◽

Physical Parameters ◽

Energy Photon ◽

P Type

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Efficiency calibration for HPGe detector by Monte Carlo efficiency transfer method

Science and Technology Development Journal - Natural Sciences ◽

10.32508/stdjns.v3i1.712 ◽

2019 ◽

Vol 3 (1) ◽

pp. 9-17

Author(s):

Le Thi Ngoc Trang ◽

Huynh Dinh Chuong ◽

Tran Thien Thanh

Keyword(s):

Monte Carlo ◽

Hpge Detector ◽

Cylindrical Sample ◽

Gamma Energy ◽

Energy Peak ◽

Full Energy Peak Efficiency ◽

Transfer Method ◽

P Type ◽

Efficiency Transfer Method ◽

Detector Model

In this paper, the Monte Carlo efficiency transfer method was used to calibrate the full energy peak efficiency (FEPE) of a coaxial p-type HPGe detector. The gamma standard radioactive sources including 22Na, 54Mn, 57Co, 60Co, 65Zn, 109Cd,133Ba, 137Cs, 154Eu, 207Bi, 241Am were measured at different positions on-center of detector with the distance of 5, 10, 15, 20, 25 cm. Besides, a cylindrical sample containing standard mixed nuclides solution was also measured at surface of the detector. The experimental FEPE curves as function of gamma energy for these geometries were determined with the coincidence-summing corrections. A HPGe detector model based on the specifications of manufacturer was built to directly calculate the FEPE for the geometries by Monte Carlo simulations with MCNP6 code. However, these simulated FEPEs show a quite high discrepancy from experimental FEPEs. Then, the FEPEs were calculated by the efficiency transfer method with the efficiency curve for point source at distance of 25 cm as the reference data. A good agreement was obtained between the calculated results by the Monte Carlo efficiency transfer method and experimental results. The comparisons between experimental and calculated FEPE showed that the relative deviations were mostly within +/-4% in the energy range of 53-1770 keV.

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Modeling the impact of uncertainty in detector specification on efficiency values of a HPGe detector using ANGLE software

Nuclear Technology and Radiation Protection ◽

10.2298/ntrp1302169m ◽

2013 ◽

Vol 28 (2) ◽

pp. 169-181 ◽

Cited By ~ 6

Author(s):

Maurice Miller ◽

Mitko Voutchkov

Keyword(s):

Hpge Detector ◽

Efficiency Curve ◽

Peak Efficiency ◽

Detector Characterization ◽

Transfer Method ◽

P Type ◽

The Impact ◽

First Time ◽

Efficiency Transfer Method ◽

Full Peak

The objective of this study is to model the impact of uncertainties in the engineering specifications of a typical p-type HPGe detector on the efficiency values when the measured soil sample is in contact geometry with the detector. We introduce a parameter named the normalized sensitivity impact which allows a comparative analysis to be made of the impact of the detector specification uncertainties and develop a correction factor table for the most important parameters. The areas of the detector most susceptible to error were found to be the crystal geometry, vacuum layer above the crystal and the bulletizing radius. In all cases the major impacts were mathematically modeled - for the first time - and found to vary either quadratically or logarithmically over the energy range of 180 keV to 1500 keV. Finally, we propose a set of detector characterization values that may be used in ANGLE for generating a reference efficiency curve using the efficiency transfer method inherent in this software. These values are to be used with the understanding that their uncertainty impact on the full-peak efficiency though not very significant in this counting arrangement, is not non-zero.

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Interface morphology of thermal oxide grown on polycrystalline silicon by different processes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131619 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1396-1397

Author(s):

H. Yen ◽

E. P. Kvam ◽

R. Bashir ◽

S. Venkatesan ◽

G. W. Neudeck

Keyword(s):

Integrated Circuits ◽

Polycrystalline Silicon ◽

Silicon Films ◽

Interface Morphology ◽

Oxide Interface ◽

Poly Silicon ◽

Thermal Oxide ◽

Grain Orientations ◽

Polycrystalline Silicon Films ◽

P Type

Polycrystalline silicon, when highly doped, is commonly used in microelectronics applications such as gates and interconnects. The packing density of integrated circuits can be enhanced by fabricating multilevel polycrystalline silicon films separated by insulating SiO2 layers. It has been found that device performance and electrical properties are strongly affected by the interface morphology between polycrystalline silicon and SiO2. As a thermal oxide layer is grown, the poly silicon is consumed, and there is a volume expansion of the oxide relative to the atomic silicon. Roughness at the poly silicon/thermal oxide interface can be severely deleterious due to stresses induced by the volume change during oxidation. Further, grain orientations and grain boundaries may alter oxidation kinetics, which will also affect roughness, and thus stress.Three groups of polycrystalline silicon films were deposited by LPCVD after growing thermal oxide on p-type wafers. The films were doped with phosphorus or arsenic by three different methods.

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