Abstract: Improved bonding surfaces for microelectronics are provided. An example method of protecting a dielectric surface for direct bonding during a microelectronics fabrication process includes overfilling cavities and trenches in the dielectric surface with a temporary filler that has an approximately equal chemical and mechanical resistance to a chemical-mechanical planarization (CMP) process as the dielectric bonding surface. The CMP process is applied to the temporary filler to flatten the temporary filler down to the dielectric bonding surface. The temporary filler is then removed with an etchant that is selective to the temporary filler, but nonreactive toward the dielectric surface and toward inner surfaces of the cavities and trenches in the dielectric bonding surface. Edges of the cavities remain sharp, which minimizes oxide artifacts, strengthens the direct bond, and reduces the bonding seam.

Abstract: Devices and techniques including process steps make use of recesses in conductive interconnect structures to form reliable low temperature metallic bonds. A fill layer is deposited into the recesses prior to bonding. First conductive interconnect structures are bonded at ambient temperatures to second metallic interconnect structures using direct bonding techniques, with the fill layers in the recesses in one or both of the first and second interconnect structures.

Abstract: Representative techniques and devices, including process steps may be employed to mitigate undesired dishing in conductive interconnect structures and erosion of dielectric bonding surfaces. For example, an embedded layer may be added to the dished or eroded surface to eliminate unwanted dishing or voids and to form a planar bonding surface. Additional techniques and devices, including process steps may be employed to form desired openings in conductive interconnect structures, where the openings can have a predetermined or desired volume relative to the volume of conductive material of the interconnect structures. Each of these techniques, devices, and processes can provide for the use of larger diameter, larger volume, or mixed-sized conductive interconnect structures at the bonding surface of bonded dies and wafers.

Abstract: Dies and/or wafers are stacked and bonded in various arrangements including stacks, and may be covered with a molding to facilitate handling, packaging, and the like. In various examples, the molding may cover more or less of a stack, to facilitate connectivity with the devices of the stack, to enhance thermal management, and so forth.

Abstract: A method for forming a bonded structure is disclosed. The method can include providing a first element having a first non-conductive region and a first conductive feature, providing a second element having a second non-conductive region and a second conductive feature, bonding the first non-conductive region to the second non-conductive region, and imparting mechanical stress to at least one of the first conductive feature and the second conductive feature. When bonding the first non-conductive region to the second non-conductive region, the first conductive feature and the second conductive feature are spaced apart by a gap. Imparting mechanical stress to the at least one of the first conductive feature and the second conductive feature reduces the gap between the first and second conductive features. The method can include annealing the first and second elements while imparting the mechanical stress to the at least one of the first conductive feature and the second conductive feature.

Abstract: Improved bonding surfaces for microelectronics are provided. An example method of protecting a dielectric surface for direct bonding during a microelectronics fabrication process includes overfilling cavities and trenches in the dielectric surface with a temporary filler that has an approximately equal chemical and mechanical resistance to a chemical-mechanical planarization (CMP) process as the dielectric bonding surface. The CMP process is applied to the temporary filler to flatten the temporary filler down to the dielectric bonding surface. The temporary filler is then removed with an etchant that is selective to the temporary filler, but nonreactive toward the dielectric surface and toward inner surfaces of the cavities and trenches in the dielectric bonding surface. Edges of the cavities remain sharp, which minimizes oxide artifacts, strengthens the direct bond, and reduces the bonding seam.

Abstract: An element and a bonded structure including the element are disclosed. The element can include a non-conductive region having a cavity extending at least partially through a thickness of the non-conductive region from the contact surface, and a contact feature formed in the cavity. The non-conductive region is configured to directly bond to a non-conductive region of a second element. The contact pad of the element is configured to directly bond to a contact pad of the second element. The contact pad can include a first conductive material and a second conductive material. The first conductive material can have a unit cell size greater than a unit cell size of the second conductive material. The first conductive material can be a metal alloying material. The first conductive material can be a metal silicide and the second conductive material can be a metal.

Abstract: Dies and/or wafers are stacked and bonded in various arrangements including stacks, and may be covered with a molding to facilitate handling, packaging, and the like. In various examples, the molding may cover more or less of a stack, to facilitate connectivity with the devices of the stack, to enhance thermal management, and so forth.

Abstract: Representative techniques and devices, including process steps may be employed to mitigate undesired dishing in conductive interconnect structures and erosion of dielectric bonding surfaces. For example, an embedded layer may be added to the dished or eroded surface to eliminate unwanted dishing or voids and to form a planar bonding surface. Additional techniques and devices, including process steps may be employed to form desired openings in conductive interconnect structures, where the openings can have a predetermined or desired volume relative to the volume of conductive material of the interconnect structures. Each of these techniques, devices, and processes can provide for the use of larger diameter, larger volume, or mixed-sized conductive interconnect structures at the bonding surface of bonded dies and wafers.

Abstract: Representative implementations of techniques and methods include chemical mechanical polishing for hybrid bonding. The disclosed methods include depositing and patterning a dielectric layer on a substrate to form openings in the dielectric layer, depositing a barrier layer over the dielectric layer and within a first portion of the openings, and depositing a conductive structure over the barrier layer and within a second portion of the openings not occupied by the barrier layer, at least a portion of the conductive structure in the second portion of the openings coupled or contacting electrical circuitry within the substrate. Additionally, the conductive structure is polished to reveal portions of the barrier layer deposited over the dielectric layer and not in the second portion of the openings. Further, the barrier layer is polished with a selective polish to reveal a bonding surface on or at the dielectric layer.

Abstract: Devices and techniques including process steps make use of recesses in conductive interconnect structures to form reliable low temperature metallic bonds. A fill layer is deposited into the recesses prior to bonding. First conductive interconnect structures are bonded at ambient temperatures to second metallic interconnect structures using direct bonding techniques, with the fill layers in the recesses in one or both of the first and second interconnect structures.

Abstract: A bonded structure can include a carrier including a first conductive contact and a second conductive contact, a first singulated element including a third conductive contact directly bonded to the first conductive contact without an adhesive, and a second singulated element including a fourth conductive contact directly bonded to the second conductive contact without an adhesive, wherein the first and second conductive contacts are spaced apart by a contact spacing of no more than 250 microns.

Abstract: Dies and/or wafers are stacked and bonded in various arrangements including stacks, and may be covered with a molding to facilitate handling, packaging, and the like. In various examples, the molding may cover more or less of a stack, to facilitate connectivity with the devices of the stack, to enhance thermal management, and so forth.

Abstract: Structures and methods for direct bonding are disclosed. A bonded structure can include a first element and a second element. The first element can include a first non-conductive structure that has a non-conductive bonding surface, a cavity that extends at least partially through a thickness of the non-conductive structure from the non-conductive bonding surface, and a first conductive feature that has a first conductive material and a second conductive material over the first conductive material disposed in the cavity. A maximum grain size, in a linear lateral dimension, of the second conductive material can be smaller than 20% of the linear lateral dimension of the conductive feature. There can be less than 20 parts per million (ppm) of impurities at grain boundaries of the second conductive material.

Abstract: A bonding method is disclosed. The bonding method can include providing a first element having a device portion and a first nonconductive bonding material disposed over the device portion of the first element. The bonding method can include providing a second element that includes a carrier. The second element having a substrate and a second nonconductive bonding material disposed over the substrate of the second element. The bonding method can include depositing a release layer between the device portion and the first nonconductive bonding material of the first element or between the substrate and the second nonconductive bonding material of the second element. The bonding method can include directly bonding the first nonconductive bonding material of the first element to the second nonconductive bonding material of the second element without an intervening adhesive.

Abstract: Methods for fabrication dielectric layers having conductive contact pads, and directly bonding the dielectric and conductive bonding surfaces of the dielectric layers. In some aspects, the method includes disposing a polish stop layer on dielectric bonding surfaces on top of a dielectric layer. A conductive layer is disposed on top of the polish stop layer and then polished to form conductive contact pads having polished conducting bonding surfaces. During the polishing process, the polish stop layer reduces rounding of dielectric edges and erosion of the dielectric bonding surfaces between closely spaced conductive bonding surfaces. The resulting polished dielectric and conductive bonding surfaces are directly bonded to dielectric and conductive bonding surfaces of another dielectric layer to form conductive interconnects.

Abstract: Disclosed herein are methods for direct bonding. In some embodiments, the direct bonding method includes providing a first element having a first bonding surface, providing a second element having a second bonding surface, slightly etching the first bonding surface, treating the first bonding surface with a terminating liquid treatment to terminate the first bonding surface with a terminating species, and directly bonding the first bonding surface to the second bonding surface without the use of an intervening adhesive and without exposing the first bonding surface to plasma.

Abstract: Representative implementations of techniques and methods include chemical mechanical polishing for hybrid bonding. The disclosed methods include depositing and patterning a dielectric layer on a substrate to form openings in the dielectric layer, depositing a barrier layer over the dielectric layer and within a first portion of the openings, and depositing a conductive structure over the barrier layer and within a second portion of the openings not occupied by the barrier layer, at least a portion of the conductive structure in the second portion of the openings coupled or contacting electrical circuitry within the substrate. Additionally, the conductive structure is polished to reveal portions of the barrier layer deposited over the dielectric layer and not in the second portion of the openings. Further, the barrier layer is polished with a selective polish to reveal a bonding surface on or at the dielectric layer.

Abstract: Devices and techniques including process steps make use of recesses in conductive interconnect structures to form reliable low temperature metallic bonds. A fill layer is deposited into the recesses prior to bonding. First conductive interconnect structures are bonded at ambient temperatures to second metallic interconnect structures using direct bonding techniques, with the fill layers in the recesses in one or both of the first and second interconnect structures.

Abstract: Devices and techniques including process steps make use of recesses in conductive interconnect structures to form reliable low temperature metallic bonds. A fill layer is deposited into the recesses prior to bonding. First conductive interconnect structures are bonded at ambient temperatures to second metallic interconnect structures using direct bonding techniques, with the fill layers in the recesses in one or both of the first and second interconnect structures.