3D integrated heterostructures having low-temperature bonded interfaces with high bonding energy

摘要

The invention relates to a process for assembling a first element that includes at least one first wafer, substrate or at least one chip, and a second element of at least one second wafer or substrate, involving the formation of a surface layer, known as a bonding layer, on each substrate, at least one of the bonding layers being formed at a temperature less than or equal to 300° C.; conducting a first annealing, known as degassing annealing, of the bonding layers, before assembly, at least partly at a temperature at least equal to the subsequent bonding interface strengthening temperature but below 450° C.; forming an assembling of the substrates by bringing into contact the exposed surfaces of the bonding layers, and conducting an annealing of the assembled structure at a bonding interface strengthening temperature below 450° C.

主权项

1. A 3D integrated heterostructure, comprising:
a first annealed element including a first substrate having one or more components, micro-components or circuits thereon, and a porous first bonding layer on the first substrate; and a second annealed element including a second substrate having one or more components, micro-components or circuits thereon, and a porous second bonding layer on the second substrate; wherein the porous first bonding layer is molecularly bonded with the porous second bonding layer to form a bonding interface between the first annealed element and the second annealed element having a bonding energy of at least 4 J/m2; and wherein the 3D integrated heterostructure is fabricated by a process including: forming the first bonding layer on the first substrate at a temperature below 250° C.; forming the second bonding layer on the second substrate at a temperature below 250° C.; annealing each of the first and second bonding layers, prior to bonding the first bonding layer to the second bonding layer, at a first annealing temperature less than 450° C. and higher than the temperature at which the first bonding layer is formed on the first substrate and higher than the temperature at which the second bonding layer is formed on the second substrate; and after bonding the first bonding layer to the second bonding layer, annealing the first and second bonding layers at or below a bonding interface strengthening temperature less than 450° C. and less than or equal to the first annealing temperature.