Study On Mechanism And Characteristics Of Trench-Planar Gate RC-LIGBT

Reverse Conducting LIGBT has obvious voltage snapback phenomenon in the forward conduction process,which seriously affects the performance of the device.The traditional structure of Separated Shortedd-Anode LIGBT(SSA-LIGBT)inhibits the snapback phen omenon by increasing the distance between the P+ collector and N+ short circuit area,but this will cause the chip area to increase,which is not conducive to power integration.Therefore,a new trench-planar gate RC-LIGBT structure is proposed,which can increase the resistance between P+ collector and N+ short-circuit region by introducing a P floating zone below the N+short-circuit region on the collector side,effectively suppress or even eliminate the snapback phenomenon,and reduce the distance between P+ collector and N+ short-circuit region.Taking 600V voltage class as an example,the operation mechanism and characteristics of the new device are studied by using Sentaurus-TCAD software for simulation.The main research contents are as follows:Firstly,the structural characteristics and operation principle of trench-plane gate RC-LIGBT were analyzed,and the blocking,forward and reverse conduction,commutation mechanism and snapback phenomenon suppression mechanism were studied.The influences of key structural parameters on the static and dynamic characteristics of the device and the snapback phenomenon were analyzed,and the optimal parameters were extracted.Secondly,the blocking,forward and reverse conduction,LIGBT turn off and integrated diode reverse recovery characteristics of trench-planar gate RC-LIGBT and SSA-LIGBT are analyzed.Compared with SSA-LIGBT,the trench-planar gate RC-LIGBT completely eliminates the snapback phenomenon at a smaller cell size and greatly reduces the power consumption.The influences of temperature and self-heating on the characteristics of trench-planar gate RC-LIGBT were studied.Thirdly,the ability to withstand latch-up of trench-planar gate RC-LIGBT and SSA-LIGBT were compared and analyzed,and the static and dynamic latch-up effects of trench-planar gate RC-LIGBT were studied.Compared to SSA-LIGBT,the trench-planar gate RC-LIGBT anti-latch-up ability is betterLastly,the ability to withstand dynamic avalanche of trench-planar gate RC-LIGBT and SSA-LIGBT was compared and analyzed,and the dynamic avalanche effect of LIGBT and integrated diode at different temperatures was studied.Compared with SSA-LIGBT,trench-planar gate RC-LIGBT has better resistance to dynamic avalanche.The research results have certain reference value for the research and development of RC-LIGBT devices.