Influence of carrier lifetime distribution on the current filament in high voltage diode

A high voltage diode with partial n⁺ adjusting region embedded at the anode side

“…The diodes were simulated by the Sentaurus-TCAD software. Auger and Shockley-Read-Hall recombination models, carrier-carrier scattering, doping dependent and electric field dependent mobility models, and avalanche generation model were taken into account [3]. An overstress condition with V dc ¼ 2:5 kV, J F ¼ 100 A/cm 2 , L ¼ 1:25 µH and di=dt ¼ 2000 A/µs was considered during reverse recovery.…”

“…A strong Egawa field [27,30,31] occurs, and this may lead to the diode failure. The electric field crowding is caused by the current filament generated by dynamic avalanche, because the electric field inside the current filament is higher [3,4,5,6,7]. For the NARD, however, electrons are injected by the npn transistor, and the electric field gradient is then given by…”

“…Great challenge for the high voltage diode above 3.3 kV in the IGBT application is to ensure the fast and soft recovery behavior, especially the dynamic avalanche capability under extreme over-stress operating condition [1,2]. Such high di=dt, high parasitic inductance L and high supply voltage V dc can provoke the appearance of dynamic avalanche, leading to the diode destruction [3,4,5,6,7]. In previous work, the p + pn − nn + structure has been proposed to improve the reverse recovery behavior [8,9].…”

“…In previous work, the p + pn − nn + structure has been proposed to improve the reverse recovery behavior [8,9]. The conventional anode structure, however, is limited to improve the fast and soft recovery behavior, because of the larger carrier concentration at the anode side than at the cathode side for the uniform carrier lifetime [3,10,11]. In addition, the carrier lifetime technologies, for instance electron or proton irradiation [12,13,14,15,16], were introduced to provide a low plasma density in front of p + emitter to improve the fast and soft recovery behavior.…”

Destruction behavior in high voltage diode with the field limiting ring termination

“…When the high voltage diode is turned off with very high di=dt, high parasitic inductance L and high supply voltage V dc , the dynamic avalanche will occur [2,3,4]. The strong current filaments induced by dynamic avalanche lead to the diode destruction [5,6,7], and the destruction positions may appear at the edge of the termination or in the active region [8,9]. Fig.…”