| Abstract |
In this paper the structure and the results of the electrical characterization of fully isolated vertical PNP transistors (VPNPs) are presented. These components can be used by devices made in VIPower (Vertical Intelligent Power) M2 technology, in all High Side Driver applications, thanks to an isolation structure based on the use of a p-type buried layer, fully enclosed in n-type, lightly doped epitaxial layers, needed as collector / drain of the vertical current flow power stage. The VPNP collector and base regions are the self-isolated p-type buried layer and the overlaying portion of the upper epilayer, respectively, while a p+ diffusion serves as emitter. A selective, low dose phosphorous implant can be considered to enhance the base doping concentration, such a structure ensures good DC performance and increases the VPNPs cut-off frequencies to values up to 50 times better than those of their lateral counterparts. |
