N.I.P. Silicon Junctions Detectors

N.I.P. Silicon junctions have been studied as particle detectors. They consist of a 1.000 Ω.cm silicon plate on each side of which respectively a P and N layer have been diffused in order to have a NIP structure. The incident particles 9 to 40 MeV alpha, are parallel with the junctions planes, and strike the detector in the I region. An energy resolution of 2 % and a good linearity of pulse height vs particle energy up to 40 MeV have been obtained. In addition, gamma rays have been detected with NIP junctions, and pulse height distribution of Co
⁶⁰¹³⁷
and Hg
²⁰³
have been stutied. The average amount of energy expended by a photoelectric electron in creating one electron-hole pair in silicon has been measured and is found to be : E = 3,53±0,07 eV for 279 keV electrons E = 3,55±0,1 eV for 660 keV electrons.