Abstract: To mount a semiconductor i.c. die on a support substrate the upper surface of the die is provided with electrically conductive bumps all of which are the same height. The bumps are provided on the ground connection pads on the upper surface of the die. The conductive pads on the die including the ground connection pads are connected to corresponding contacts on the upper surface of the substrate on which the die is mounted. Additionally, a thermally conductive, electrically conductive slug overlies the die and is mounted on and bonded to the bumps. The slug provides required heat removal from the die and also provides necessary ground connection to circuitry within the die.