Characteristics of a large-area lithium-ion-drifted silicon semiconductor detector

Abstract

The large-area lithium-ion-drifted silicon semiconductor detector of 70 mm diameter and 1 mm thickness is fabricated by the improved lithium-ion drift method. The electric characteristics of the reverse-bias versus reverse-current and the reverse-bias versus capacitance are investigated. The energy spectra of α-particles from 239 94Pu, 241 96Am and 244 96Cm and internal conversion electrons from 207 83Bi are measured. The energy resolutions are 90 keV (fwhm) for α-particles and 80 keV (fwhm) for electrons, respectively. The characteristics of the pulse height versus reverse-bias and the pulse height uniformity over the entire area of the detector are investigated. The results show that the pulse height is saturated above 150 V and that the complete uniformity is obtained.