This paper presents double-sided nickel-tin transient liquid phase (Ni-Sn TLP) bonding technology and its application to double-sided cooling structures used in automotive power modules. Double-sided cooling is an emerging solution for heat dissipation problems inside compact power modules (used in electrified vehicles) and requires components providing highlevel reliability. This requirement is satisfied by Ni-Sn TLP bonding technology facilitating a high re-melting temperature reaching ∼794 °C. Double-sided Ni-Sn TLP bonding is demonstrated using conventional power diodes having nickel layers on both sides. Electrical characterizations of the doubleside bonded diodes reveal consistent and reproducible bonding quality. In addition, excellent high temperature reliability of double-sided TLP bonding is exhibited by high temperature storage (at 300 °C) and thermal cycling (from -40 to 200 °C) evaluations. This presentation is the first time demonstration of double-sided TLP bonding using active power devices.