Characterization and TCAD modelling of termination structures for silicon radiation detectors

We have recently proposed a novel junction termination structure for silicon radiation detectors, featuring all-p-type multiguard and scribe-line implants, with metal field-plates completely covering the gap between the implanted rings. The structure is intended for detector long-term stability enhancement even in adverse ambient conditions and for fabrication-process simplification. A thorough static characterization, including stability measurements in varying humidity conditions, has been carried out on a variety of samples fabricated at ITC-irst. Comparisons with diodes featuring an n-type implant along the border—or no edge structure at all—have been performed. The new structures show stable behaviour at relatively high bias (∼200 V), also in the presence of wide humidity changes (1–90%). A good qualitative agreement has been obtained between experimental results and simulation predictions, allowing to gain deep insight into the physical behaviour of the device.