A semiconductor assembly, a packaging structure, and associated method for corner stress reduction in semiconductor devices. The assembly includes a plurality of semiconductor dies and a plurality of spacers. Each spacer in the plurality of spacers is disposed between and configured to separate two semiconductor dies in the plurality of semiconductor dies. At least one spacer in the plurality of spacers has at least one extended spacer corner feature configured to extend toward at least one corner of at least one semiconductor die in the plurality of semiconductor dies disposed adjacent to the at least one spacer. At least one extended spacer corner feature is configured to reduce stress on at least one semiconductor die.

According to the present disclosure, upper and lower substrates may be electrically connected to a lead frame, such that wire bonding may be excluded, and electrical connection and heat dissipation may be performed without a spacer by improving a connection structure in the upper and lower substrates. In addition, a power module is introduced in which because a spacer for forming a large current path may be excluded, a current path may be shortened, such that power performance may be improved, an internal space may be additionally provided, costs may be reduced, and an overall size of the power module may be reduced.

A microelectronic assembly comprises a first microelectronic component; a second microelectronic component under an area of the first microelectronic component and coupled to the first component through first interconnect structures within a central region of the area, and second interconnect structures within a peripheral region of the area, adjacent to the central region. A heterogenous dielectric surface on the first or second component or both and within a gap between the first and second components has a first surface composition within the central region and at least a second surface composition within the peripheral region.

A semiconductor element bonding substrate according to the present invention includes an insulating plate, and a metal pattern bonded to a main surface of the insulating plate. A main surface of the metal pattern on an opposite side of the insulating plate includes a bonding region to which a semiconductor element is bonded by a solder. The metal pattern includes at least one concave part located in the main surface. The at least one concave part is located closer to an edge of the bonding region in relation to a center part of the bonding region in the bonding region.