A magnetic tunnel junction (MTJ) containing device is provided that includes an undercut conductive pedestal structure having a concave sidewall positioned between a bottom electrode and a MTJ pillar. The geometric nature of such a conductive pedestal structure makes the pedestal structure unlikely to be resputtered and deposited on a sidewall of the MTJ pillar, especially the sidewall of the tunnel barrier of the MTJ pillar. Thus, electrical shorts caused by depositing resputtered conductive metal particles on the sidewall of the tunnel barrier of the MTJ pillar are substantially reduced.