Fan-out microelectronic unit wlp having interconnects comprising a matrix of a high melting point, a low melting point and a polymer material

Abstract

A microelectronic package includes a microelectronic unit and a substrate. The microelectronic unit includes a microelectronic element having contacts on a front face. A dielectric material has a first surface substantially flush with the front face of the microelectronic element. Conductive traces have at least portions extending along the front face away from the contacts, at least some of which also extend along the first surface of the dielectric material. Contacts are connected with the traces, at least some of which are disposed at the first surface of the dielectric material. The substrate has first and second opposed surfaces and an edge extending therebetween, the first surface facing the front face of the microelectronic unit, and the second surface having a plurality of terminals thereon configured for electrical connection with at least one external component. Masses of conductive matrix material join the terminals with the redistribution contacts.