Accurate Depth Profiling Through Energy-Dependent Pulse Height Deficit Compensation in Gas Ionization Detectors

Abstract

The impact of the pulse height deficit effect in gas ionization detectors on the accurate extraction of depth information from heavy ion elastic recoil detection spectra has been investigated. Thin GaN films and GexSi1-x/Si heterostructures have been analyzed with a 200 MeV 197Au beam. Employing an empirical parameterisation of the pulse height deficit, a global energy calibration of the detector can be achieved. Energy spectra have been compared, calibrated with either a constant or a full energy-dependent compensation for the deficit. A constant compensation results in significant distortion of the extracted depth profile for heavier ions, whereas an energy-dependent compensation yields true concentration-depth profiles.