Proton irradiation results of p+/n−/n+ Cz-Si detectors processed on p-type boron-doped substrates with thermal donor-induced space charge sign inversion

When processing boron-doped p-type high-resistivity Czochralski Silicon (Cz-Si), the Thermal Donor (TD) generation process can be utilized in order to produce p+/n−/n+ detectors. The last thermal process step, i.e. the sintering of aluminum, is intentionally carried out at the temperature where TDs are created. Due to the generated donors the p-type bulk will eventually be compensated to n-type bulk. With this method it is possible, with low costs and with a process of low thermal budget, to fabricate detectors with high oxygen concentration. Moreover, the full depletion voltage of detectors could be tailored between a wide range from 30 V up to almost 1000 V by changing heat treatment duration at 400-450 °C from 20 to 80 min. The Space Charge Sign Inversion (SCSI) in the TD generated devices has been verified by the Transient Current Technique (TCT). The results of 24 GeV/c proton irradiation to fluences up to 5×1014 p/cm2 show a very small increase of full depletion voltage.