Electric field distribution using floating metal guard rings edge-termination for Schottky diodes

Diamond Schottky barrier diodes with floating metal guard ring as edge termination have been fabricated and characterized. The influences of spacing between two consecutive rings and number of rings on breakdown voltage and surface electric field distribution were investigated. Electron beam induced current (EBIC) analysis revealed the efficiency of floating metal guard rings edge termination for a fixed gap between two rings. The obtained high reverse leakage currents were mainly related to the presence of hotspots, influencing the breakdown voltage and avoiding avalanche phenomena from happening within the material. These high-field regions emerging under high reverse bias highlight the crowding of electric field causing a premature breakdown. The combination of the hotspots and the possible presence of electric arc between the rings at high bias may give rise to an increase of leakage current. [Display omitted] •SBDs with floating metal guard ring have been successfully fabricated.•EBIC intensity revealed the effectiveness of FMGR with 300 nm ring distances.•Hotspots and arcing induces high reverse leakage current increase.•Correlation between hotspots and damaging level of the breakdown observed.