Method to electrically connect chip with top connectors using 3D printing

A method for fabricating a three-dimensional (3D) electronic device, the method comprising:

• iteratively applying layers of a liquid support material by a laser-induced forward transfer (LIFT) process to a printed circuit board (PCB) having a first contact pad and an electronic component thereon, the PCB being disposed on a stage in a work area, and the electronic component having a mounting package and a second contact pad protruding from a top surface of the mounting package, wherein each respective layer of the liquid support material is applied in a gap between the first contact pad and the second contact pad and, after application, the respective layer of the liquid support material is cured to form a solid support structure by cooling and/or exposure to ultraviolet (UV) radiation, such that after application and curing of a number of successive layers of the liquid support material, a solid support structure is formed between the first contact pad and the second contact pad, a cross section of the solid support structure having a staircase side profile with multiple steps, with a height of each of the steps being less than a thickness of the electronic component, and a top most one of the steps contacting (i) a portion of the top surface of the mounting package and (ii) a side surface of the second contact pad protruding from the top surface of the mounting package;
• printing a layer of conductive material on the staircase side profile of the solid support structure by the LIFT process;
• drying the layer of conductive material by heat so as to form a dried layer of conductive material;
• sintering metal particles in the dried layer of conductive material using a laser beam to form a conductive layer that electrically connects the second contact pad of the electronic component to the first contact pad of the PCB;
• and
• encapsulating the first and second contact pads, the conductive layer, and the electronic component in an encapsulant by the LIFT process.