A method of attaching a pair of chips (a and b) shown in Figure (150), each having primary contacts that can be mated to each other, involves forming one or more secondary contacts on each of the two chips of a shape sufficient to prevent an initial attachment material from contacting any of the primary contacts during a preliminary attachment operation, the secondary contacts further having a height that will prevent the primary contacts from touching when the secondary contacts are brought into contact with each other, bringing the secondary contacts into closer and closer aligned proximity to each other at least until the primary contacts touch in a first phase, and heating the primary contacts until material between each of the corresponding primary contacts of each of the chips in the pair forms an electrical connection