Simulation of the small pixel effect contributing to a low fill factor for pixellated Low Gain Avalanche Detectors (LGAD)

• DOI: 10.1016/j.nima.2021.165746
• Publication Date: 2021-09-20T01:57:40Z
• Authors: Neil Moffat; Richard Bates
• Keywords: Dot pitch

Small pixel Low Gain Avalanche Detectors (LGADs) have the potential, with a low gain in region of ten and pitch 55μm, to detect high spatial resolution < 1 keV photons by sub-threshold detection hybrid detector. TCAD simulation has been performed establish minimum pitch, quantified terms fill factor, achievable current process technology. The results show, using Micron Semiconductor Ltd LGAD as typical example process, factor 55μm is 0%, that small device not possible standard Increasing 110μm 220μm increases 17.7% 47.4% respectively. explanation for shown simulation, due distortions electric field near protective structures around each implant known Junction Termination Extensions (JTE). For JTEs are very close together which causes signal charges under flow away from multiplication be collected on JTE. To improve two methods mentioned developed other groups, Trench-Isolated LGADs Inverse , could vastly fine detectors.