Commissariat a L'energie Atomique Et Aux Energies Alternatives

Stmicroelectronics (Crolles 2) Sas

Stmicroelectronics (Rousset) Sas

Pierric Gueguen

Lea Di Cioccio

Maurice Rivoire

Laurent Vandroux

Léa Di Cioccio

Francois Grossi

A method for bonding a first surface provided with at least one copper area surrounded by a silicon oxide area to a second surface includes an operation of treatment of the first surface by a plasma, before placing the first surface in contact with the second surface. The plasma is formed from a gas source containing a silicon oxide nitriding agent and a copper oxide reducing agent containing hydrogen. The gas source may include an Nand NHand/or Hgas mixture or a NO and Hgas mixture, or ammonia, which is then used both as a nitriding agent and as a reducing agent. The plasma obtained from this gas source then necessarily contains nitrogen and hydrogen, which enables, in a single operation, to provide a high-performance bonding between the first and second surfaces.

Treatment, before the bonding of a mixed Cu-oxide surface, by a plasma containing nitrogen and hydrogen

A method for modifying crystalline structure of a copper element with a planar surface, including: a) producing a copper standard having large grains, wherein the standard includes a planar surface, b) reducing roughness of the planar surfaces to a roughness of less than 1 nm, c) cleaning the planar surfaces, d) bringing the two planar surfaces into contact, and e) annealing.

Method for modifying the crystalline structure of a copper element

A process of assembly by direct bonding of a first and second element, each having a surface including copper portions separated by a dielectric material, the process includes: polishing the surfaces such that the surfaces to be assembled allow assembly by bonding; forming a diffusion barrier selectively in copper portions of the first and second elements, wherein the surface of the diffusion barrier of the first and second elements is level with the surface, to within less than 5 nanometers; and bringing the two surfaces into contact, such that the copper portions of one surface cover at least partly the copper portions of the other surface, and such that direct bonding is obtained between the surfaces.

Process for direct bonding two elements comprising copper portions and portions of dielectric materials

A method for bonding a first copper element onto a second copper element including forming a crystalline copper layer enriched in oxygen on each of surfaces of each of the first and second elements through which the elements will be in contact, the total thickness of both layers being less than 6 nm, which includes: a) polishing the surfaces so as to obtain a roughness of less than 1 nm RMS, and hydrophilic surfaces, b) cleaning the surfaces to suppress presence of particles due to the polishing and the major portion of corrosion inhibitors, and c) putting both crystalline copper layer enriched in oxygen in contact with each other.

Simplified copper-copper bonding

A method of forming, on a surface of a substrate, at least one hydrophilic attachment area for the purpose of self-assembling a component or a chip, in which a hydrophobic area, which delimits the hydrophilic attachment area, is produced.

Growing community of inventors

Echirolles, France

Pierric Gueguen