Investigation of the type inversion phenomena: resistivity and carrier mobility in the space charge region and electrical neutral bulk in neutron irradiated silicon p+-n junction detectors

The changes of effective dopant concentration in the space-charge region (SCR) of neutron irradiated silicon detectors are investigated near the type inversion point. In addition to conventional capacitance-voltage (C-V) measurements, the transient current technique using a laser light excitation which is adsorbed at 10 μm in the silicon is also applied. The details of transient current response in irradiated silicon detectors are discussed. This gives the possibility for determining the effective dopant concentration in the SCR as well as properties in the electrically neutral bulk of silicon detectors