A method comprising: attaching a first metal layer of a direct-bonded copper ("DBC") substrate to at least one lead with an ultrasonic weld thereby forming an assembly, wherein the ultrasonic weld mechanically and electrically couples the first metal layer to the lead, wherein the DBC substrate comprises an insulative layer disposed between the first metal layer and a second metal layer , and wherein an entire surface of the first metal layer contacts the insulative layer after the attaching; wherein the at least one lead comprises a contact pad , having an upper surface and a lower surface, wherein the at least one lead is joined to the first metal layer through the lower surface of the contact pad , and wherein the ultrasonic weld comprises applying an ultrasonic head to the upper surface of the contact pad ; attaching one and only one power semiconductor integrated circuit die to the first metal layer of the assembly; surrounding at least the first metal layer and the one and only one power semiconductor integrated circuit die with an amount of encapsulant ; leaving at least a portion of the second metal layer of the DBC substrate exposed to form a back side of a packaged power integrated circuit device ; and leaving a portion of the lead exposed, wherein the second metal layer 1s electrically insulated from the first metal layer , and wherein the packaged power integrated circuit device (3 7) comprises only one semiconductor die, wherein the ultrasonic weld is formed by clamping the DBC substrate and the at least one lead together, wherein a welding pressure of the ultrasonic weld is not more than 0.05 MPa, wherein the ultrasonic weld decreases a thickness of a region of the first metal layer in contact with the at least one lead by 0.05 mm. attaching a first metal layer of a direct-bonded copper ("DBC") substrate to at least one lead with an ultrasonic weld thereby forming an assembly, wherein the ultrasonic weld mechanically and electrically couples the first metal layer to the lead, wherein the DBC substrate comprises an insulative layer disposed between the first metal layer and a second metal layer , and wherein an entire surface of the first metal layer contacts the insulative layer after the attaching; wherein the at least one lead comprises a contact pad , having an upper surface and a lower surface, wherein the at least one lead is joined to the first metal layer through the lower surface of the contact pad , and wherein the ultrasonic weld comprises applying an ultrasonic head to the upper surface of the contact pad ; attaching one and only one power semiconductor integrated circuit die to the first metal layer of the assembly; surrounding at least the first metal layer and the one and only one power semiconductor integrated circuit die with an amount of encapsulant ; leaving at least a portion of the second metal layer of the DBC substrate exposed to form a back side of a packaged power integrated circuit device ; and leaving a portion of the lead exposed, wherein the second metal layer 1s electrically insulated from the first metal layer , and wherein the packaged power integrated circuit device (3 7) comprises only one semiconductor die, wherein the ultrasonic weld is formed by clamping the DBC substrate and the at least one lead together, wherein a welding pressure of the ultrasonic weld is not more than 0.05 MPa, wherein the ultrasonic weld decreases a thickness of a region of the first metal layer in contact with the at least one lead by 0.05 mm. <EOS>