Two different diode technology concepts are compared with respect to cosmic radiation hardness and electrical performance [1]. Ion irradiation experiments reveal that diodes with highly doped and deeply diffused pn-junctions can survive cosmic radiation induced streamer events, explaining the observed extraordinary high cosmic radiation hardness. The electrical performance of these diodes is found to be weaker than that of diodes with shallow pn-junctions, which show a conventional level of cosmic radiation hardness. For an overall optimization, cosmic radiation hardness of diodes should be high enough for the required application on system level, without compromising diode performance too much.