Fundamental effects and non-linear Si detector response

Research output: Contribution to journalArticle


Non-linearity in the energy response of a Si p-i-n charged particle detector has been studied for incident particles with Z(1) between 3 and 26, and energies between 0.1 and 0.7 MeV per nucleon. Although the data closely followed a straight line relations, fitting of the data to a third order polynomial revealed that the response exhibited a persistent curvature that acted to reduce the energy interval spanned by a channel as the energy increased. The curvature increased as Z(1) increased from 4 to 8 and then systematically decreased. The curvature is larger and has the opposite energy dependence to the stopping in a dead entrance window and the energy deposited in non-ionising processes within the active layer. The plasma recombination dependence on the average stopping along the plasma column may account for the reduction in curvature as Z(1) increases from 9 to 25 but cannot explain the net effect. The low-energy increase in energy channel span, which has also been reported by others, might be associated with electron excitation in resonant and direct classical quasi-elastic collisions for low-energy ions, or less likely, electronic non-linearity's associated with Z(1) and energy dependent time structure in the current pulse from the detector. Simple interpolation of the window-loss corrected polynomial coefficients is the best approach if the calibration for Z(1) cannot be established directly.


  • Harry J Whitlow
  • YW Zhang
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Subatomic Physics


  • time of flight, electronic stopping, Si charged-particle detector, energy calibration, ERDA, p-i-n diode
Original languageEnglish
Pages (from-to)375-378
JournalNuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms
Issue number1-4
Publication statusPublished - 2002
Publication categoryResearch

Bibliographic note

The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Nuclear Physics (Faculty of Technology) (011013007)