Method of bonding and resulting product

A method of bonding a first body to a second body comprising the steps of:

• disposing between the first body and the second body, a freestanding reactive multilayer foil;
• pressing the bodies together against the foil;
• and
• igniting the reactive foil.

A method of making a reactive multilayer foil comprising the steps of:

• providing a substrate having a surface including a plurality of preformed openings, bumps, or particles of thickness or depth similar to or greater than the multilayer foil to be deposited;
• depositing on the surface a plurality of layers to form the reactive multilayer foil;
• and
• separating the multilayer foil from the substrate.

A method of making a reactive multilayer foil comprising the steps of:

• providing a flat substrate;
• depositing on the substrate a plurality of layers to form a reactive multilayer foil;
• depositing a masking layer on top of the reactive foil;
• patterning the masking layer with a plurality of holes;
• etching the reactive foil through the holes;
• and
• separating the multilayer foil from the substrate.

A method of making a reactive multilayer foil comprising the steps of:

• providing a flat substrate;
• depositing on the substrate a plurality of layers to form a reactive multilayer foil;
• and
• mechanically pressing a plurality of holes into the reactive foil.

A method of bonding a first body to a second body comprising the steps of:

• disposing between the first body and the second body, a reactive multilayer foil and at least one meltable joining material, the reactive multilayer foil having a plurality of openings through the thickness of the foil;
• pressing the bodies together against the foil and the joining material;
• and
• igniting the reactive foil to melt the joining material and permit the melted material to flow through the openings to join the first and second bodies.

A method of connecting a semiconductor or microelectronic device having one or more electrical contacts to a substrate having one or more receiving contacts, comprising the steps of:

• disposing between the device and the substrate a reactive multilayer foil composed of one or more first regions that can react exothermically to form electrically conductive regions and one or more second regions which are non-conductive or react to form non-conductive material;
• registering the contacts of the device, the contacts of the substrate and the first regions of the foil,
• pressing the device and the substrate together against the foil;
• and
• igniting the foil.

A method for bonding a first body to a second body comprising the steps of:

• disposing between the first body and the second body, a reactive multilayer foil comprising a plurality of successive exothermic reactive layers that react to form a joining material;
• pressing the bodies together against the foil;
• and
• igniting the foil.

A method of bonding a first body to a second comprising the steps of:

• disposing between the first body and the second body, a freestanding reactive multilayer foil and at least one layer of meltable joining material;
• pressing the bodies together against the foil and joining material;
• and
• igniting the reactive foil to melt the joining material.