A method for assembling a first substrate and a second substrate via metal adhesion layers, the method including: depositing, on a surface of each of the first and second substrates, a metal layer with a thickness controlled to limit surface roughness of each of the deposited metal layers to below a roughness threshold; exposing the metal layers deposited on the surface of the first and second substrates to air; directly adhering the first and second substrates by placing the deposited metal adhesion layers in contact, the surface roughness of the contacted layers being that obtained at an end of the depositing. The adhesion can be carried out in the air, at atmospheric pressure and at room temperature, without applying pressure to the assembly of the first and second substrates resulting from directly contacting the deposited metal adhesion layers.

A method for assembling a first substrate and a second substrate via metal adhesion layers, the method including: depositing, on a surface of each of the first and second substrates, a metal layer with a thickness controlled to limit surface roughness of each of the deposited metal layers to below a roughness threshold; exposing the metal layers deposited on the surface of the first and second substrates to air; directly adhering the first and second substrates by placing the deposited metal adhesion layers in contact, the surface roughness of the contacted layers being that obtained at an end of the depositing. The adhesion can be carried out in the air, at atmospheric pressure and at room temperature, without applying pressure to the assembly of the first and second substrates resulting from directly contacting the deposited metal adhesion layers.

A layered bonding material 10 includes a base material 11, a first solder section 12a stacked on a first surface of the base material 11, and a second solder section 12b stacked on a second surface of the base material 11. A coefficient of linear expansion of the base material 11 is 5.5 to 15.5 ppm/K, the first solder section 12a and the second solder section 12b are made of lead-free solder, and both of a thickness of the first solder section 12a and a thickness of the second solder section 12b are 0.05 to 1.0 mm.

A highly reliable bonded structure having excellent thermal fatigue resistance characteristics and thermal stress relaxation characteristics is provided. The bonded structure of the present invention comprises a first member, a second member capable of being bonded to the first member, and a bonding part interposed between a first bond surface at the first member side and a second bond surface at the second member side to bond the first member and the second member. The bonding part has at least a bonding layer, a reinforcing layer, and an intermediate layer. The bonding layer is composed of an intermetallic compound and bonded to the first bond surface.

A highly reliable bonded structure having excellent thermal fatigue resistance characteristics and thermal stress relaxation characteristics is provided. The bonded structure of the present invention comprises a first member, a second member capable of being bonded to the first member, and a bonding part interposed between a first bond surface at the first member side and a second bond surface at the second member side to bond the first member and the second member. The bonding part has at least a bonding layer, a reinforcing layer, and an intermediate layer. The bonding layer is composed of an intermetallic compound and bonded to the first bond surface.

A heat-dissipating device includes at least one heat-dissipating surface and a micro-sized cooling mechanism formed directly on the heat-dissipating surface by an additive manufacturing process. The cooling mechanism includes at least one fluid passage, such as a micro-hose, for carrying a cooling medium from a coolant source directly to the heat-dissipating surface. The cooling mechanism is fluidly sealed to the heat-dissipating surface such that the cooling medium is in thermal contact directly with the heat-dissipating surface.

Method for producing a composite structure comprising the direct bonding of at least one first wafer with a second wafer, and comprising a step of initiating the propagation of a bonding wave, where the bonding interface between the first and second wafers after the propagation of the bonding wave has a bonding energy of less than or equal to 0.7 J/m.sup.2. The step of initiating the propagation of the bonding wave is performed under one or more of the following conditions: placement of the wafers in an environment at a pressure of less than 20 mbar and/or application to one of the two wafers of a mechanical pressure of between 0.1 MPa and 33.3 MPa. The method further comprises, after the step of initiating the propagation of a bonding wave, a step of determining the level of stress induced during bonding of the two wafers, the level of stress being determined on the basis of a stress parameter Ct calculated using the formula Ct=Rc/Ep, where: Rc corresponds to the radius of curvature (in km) of the two-wafer assembly and Ep corresponds to the thickness (in m) of the two-wafer assembly. The method further comprises a step of validating the bonding when the level of stress Ct determined is greater than or equal to 0.07.

An electronic device includes a semiconductor die having a lower surface, a sintered metallic layer underlying the lower surface of the semiconductor die, a conductive layer underlying the sintered metallic layer, and a conductive substrate underlying the conductive layer.

An electronic device includes a semiconductor die having a lower surface, a sintered metallic layer underlying the lower surface of the semiconductor die, a conductive layer underlying the sintered metallic layer, and a conductive substrate underlying the conductive layer.

Technologies are generally described related to three-dimensional integration of integrated circuits (ICs) with spacing for heat dissipation. According to some examples, a self-aligned silicide may be formed in a temporary silicon layer and removed subsequent to bonding of the wafers to achieve improved contact between the combined ICs and enhanced heat dissipation through added spacing between the ICs.