The Characterization of Proton Irradiated BaSrFBr:Eu Film by the Coincidence Doppler Broadening Positron Annihilation Spectroscopy

Enhance signal-to-noise ratio, slow positron coincidence Doppler Broadening method has been applied to study of characteristics of Nb 3 Ge superconductor film, which were performed from 20 K to 300 K sample temperature near Tc of it. In this investigation the numerical analysis of the Doppler spectra was employed to the determination of the shape parameter, S, defined as the ratio between the amount of counts in a central portion of the spectrum and the total counts of whole spectrum. The S-parameter values between 0.598 and 0.594 were decreased while the temperature were decreasing, that indicated the voids into the samples. The temperature dependence came from specific positron trapping rate into the vacancy-type defects. It is believed that the positrons annihilate with normal-electrons instead of super-electrons in the Nb3Ge superconductor.

The Characterization of Nb₃Ge by Slow Positron Annihilation Spectroscopy

Lee¹,

Bae²

2010

Proton Irradiated Cz-Si by the Coincidence Doppler Broadening Positron Annihilation Spectroscopy

Lee¹,

Lee²

2011

볼륨 결함 측정에도 이용되고 있으며 물질의 전자 [7,8,9] Trans. 2, 1627 (1971).[5] H. E. Collins, Met. Trans. 5, 189 (1974).[6] Chunqing He, M. Muramatsua, T. Ohdairaa, N. (Received July 19, 2011, Revised August 16, 2011, Accepted August 17, 2011 It is described that the proton beam induces micro defects and electronic deep levels in Cz single crystal silicon. Enhance signal-to-noise ratio, Coincidence Doppler Broadening Positron Annihilation Spectroscopy has been applied to study of characteristics of p type and n type silicon samples. In this investigation the numerical analysis of the Doppler spectra was employed to the determination of the shape parameter, S, defined as the ratio between the amount of counts in a central portion of the spectrum and the total counts of whole spectrum. The samples were exposed by 4.0 MeV proton beams ranging from 0 to 10 ∼ 14 ptls. The S-parameter values were increased as increasing the irradiated proton beam, that indicated the defects generate more.

Investigation of Proton Irradiated Effect on n, p type Silicon by Positron Annihilation Method

Lee¹

2012

It is described that the proton beam induceds micro-size defects and electronic deep levels in n or p type single crystal silicon. Positron lifetime and Coincidence Doppler Broadening Positron Annihilation Spectroscopy were applied to study of characteristics of p type and n type silicon samples. In this investigation the numerical analysis of the Doppler spectra was employed to the determination of the shape parameter, S, defined as the ratio between the amount of counts in a central portion of the spectrum and the total counts of whole spectrum. The samples were exposed by 3.98 MeV proton beams ranging between 0 to ∼10 14 particles. The S-parameter values strongly depend on the irradiated proton beam, that indicated the defects generate more. Positron lifetime shows that positrons trapped in vacancies and lifetime τ 2 increased according to proton irradiation.