Optimization and design of diamond High Voltage power devices

International audienceDiamond, thanks to its outstanding physical properties, is theultimate semiconductor to go beyond the classical design trade off in powerdevices. The two switches (Schottky Barrier Diode and Field EffectTransistor (FET)) which will allow fabricating a full diamond commutation cellfor power converters are under investigation. Nevertheless, to take benefitof diamond properties in such components a particular attention has to beenpaid to the design of the structure based on the most recent experimentalcharacterization of diamond physical parameters. In this work, we focusedon the optimization of the Ron.S(BV) figure of merit while sizing the drift layerof unipolar high voltage diamond power devices. Based on the ionizationintegral calculation with diamond adapted impact ionization coefficients in aone dimensional semi-analytical approach of the breakdown voltage, weperformed an accurate analysis of the reciprocal punch through factor asfunction of the breakdown voltage. In the case of diamond FETs, we alsoevaluated the minimum channel dose (doping level times thickness) avoidingthe pinch of the channel and so ensuring a good operating regime fordiamond p-FET. These results will allow proposing preliminary design rulesto fabricate working unipolar diamond power devices. However we will showthat thickness and doping required for such structures are quite challengingfor crystal growth in the context of high voltage power devices