Within the CoLPACK project we will develop an advanced Chip-On-Board (COB) packaging technique suitable for 3D PCB stacking and realisation of more compact size-sensitive electronic products in medical applications, LED lighting and portable consumer electronics. For the first time we will assemble lateral ultra-high voltage (UHV) IGBT dies directly onto the application PCB using flip-chip technique. Proprietary lateral >800V IGBTs with compelling area and switching advantages over competitive solutions have been recently developed by Cambridge Microelectronics. By using a lateral IGBT, where all terminals are on the front side of the die, UHV bondwires (used to contact UHV terminal which is on the back-side of the vertical IGBT die) will be eliminated from the PCB assembly. This is the first time bare UHV devices will be used for flip-chip, COB assembly and 3D PCB stacking.