Optimized local lifetime control for the superior IGBTs

Application of local lifetime control by helium ion irradiation was studied to improve an IGBT´s performance. Light ion irradiation enables the formation of recombination layers in silicon power devices at favorable area by accommodation of ion accelerative voltage, resulting in reduction of turn-off power dissipation loss. In a practical application of the ion irradiation, relatively large scattering of performance could take place because of the relatively large scattering of Si wafer thickness. However, over 20% reduction of the turn-off loss was successfully achieved without a large scattering of trade-off characteristics by an irradiation method which utilizes the defects formed by the passing ions for the first time