Proton irradiation for improved GTO thyristors

We apply proton irradiation to tailor the lifetime in large area 2.5 kV and 4.5 kV standard GTO thyristors. The devices are already optimised with respect to the trade-offs between physical properties. Nevertheless, it is shown that proton irradiation allows for individual optimisation of I_GT and E_off, increasing the degree of freedom for the GTO design. These two parameters can thus be trimmed independently after processing and before encapsulation