The Recearch Of Snape-off Reserve Recover Current Of Diode

The process of switching the pin rectifier from the on-state to the blocking state isreferred to as the reverse recovery. During the reverse recovery, the reverse recoverycurrent may generate snape-off. Because of three different generation mechanisms, thereare three types of snape-off current which were mainly analysed and researched in thispaper.Firstly, the reason of the snape-off current was analysed in theory. And then threetypes of the snape-off is simulated by the the software of Silvaco TCAD during the reverserecovery process. The distribution of the carrier concentration in the pin diode is simulated,too. Lastly, The generation mechanisms of these three types of snape-off current areanalysed by researching the distribution of carriers.Then, the buffer layer is introduced for soft recovery. It is simulated by SilvacoTCAD that buffer layer is useful for punch through diode but not the non-punch throughdiode. The reverse recovery peak current has reduced and the reverse recovery softnessfactor is enhanced in punch through diode with buffer layer. This is the theoretical basis forsolving the snape-off.According to the analyzing result. Buffer layer is adopted to solve the snape-offduring the reserve recovery phase. It is verified by simulation that the snape-off current canbe avoided by pin diode structure with buffer layer between n-and n+.