Low energy response of silicon pn-junction detector

The response function of implanted silicon detectors in the soft X-ray region (150 eV-6 keV) has been measured. To reduce signal charge loss in the highly doped p(+)-region just beneath the detector surface, different techniques of producing shallow doping profiles and enhancing the electric field at the pn-junction are presented. The spectroscopic resolution could be improved significantly. On (100) detector material, a peak to valley ratio of 5700:1 for the mangan K-alpha line was achieved. The measured pulse-height distributions were fitted by a detector model, taking the doping profile of the entrance window into account. The results of the fit were in excellent agreement with the measurement data over the entire energy range.