Characterization of 2D dopant profiles for the design of proton implanted high-voltage super junction

SJ transistors were successfully realized by proton implantation, whose hydrogen related donors were found to be responsible for the effective n-type doping of the undoped layers. Implantation ranges up to 40 μm have been reached using relatively moderate acceleration voltages. LM after selective etching permitted a rough estimate of the columns composition while SCM permitted an exhaustive characterization at a higher resolution. The approach chosen in this study permitted to evaluate the lateral extension of the boron bubbles and to quantify the overcompensation effect resulting from donor implantation. The slight mismatch of the implants as resulting from the masking effect of the metallization could be identified as well as the incomplete column formation. The results of our study showed how SCM can play a key role in the characterization of proton implanted devices due to its dependency only on the distribution of the carriers and not on the particular donor which determines it. SCM results a valuable tool which can strongly support the process simulation especially when complex physics models hinder reliable interpretations of the simulations.