A multilayer electronics assembly and associated method of manufacture are provided. The multilayer electronics assembly includes a plurality of stacked substrate layers. Each of the substrate layers is fusion bonded to at least an adjacent one of the plurality of substrate layers. A first discrete electrical circuit component is bonded to a first layer of the plurality of layers. A bonding material is interposed between the discrete electrical circuit component and the first layer. The bonding material has a reflow temperature at which the bonding material becomes flowable that is higher than a fusion bonding temperature of the substrate layers.

A multilayer electronics assembly and associated method of manufacture are provided. The multilayer electronics assembly includes a plurality of stacked substrate layers. Each of the substrate layers is fusion bonded to at least an adjacent one of the plurality of substrate layers. A first discrete electrical circuit component is bonded to a first layer of the plurality of layers. A bonding material is interposed between the discrete electrical circuit component and the first layer. The bonding material has a reflow temperature at which the bonding material becomes flowable that is higher than a fusion bonding temperature of the substrate layers.

A joined structure includes: a first member; and a second member that faces the first member and that is joined to the first member via a joining layer. The joining layer includes a metal material and a solder material, apart of the metal material has at least one pore, and the solder material is located in a part of an internal area of the at least one pore. Also disclosed is a joining method that makes it possible to produce the joined structure. Further disclosed is a joining material used in the joining method. The joining method makes it possible to achieve non-pressurization sintering processes while maintaining high precise thickness of a joining layer between the first layer and the second layer based on the spacer.

A method of bonding a plurality of die having first and second metal layers on a die surface to a board, comprising placing a first die onto a board comprising one of a ceramic or substrate board or metal lead frame having a solderable surface and placing the first die and the board into a reflow oven. The method includes reflowing at a first reflow temperature for a first period until the first metal board layer and at least one of the first and second metal die layers of the first die form an alloy to adhere the first die to the board. The alloy has a melting temperature higher than the first reflow temperature. Accordingly, additional die may be added at a later time and reflowed to attach to the board without causing the bonding of the first die to the board to fail.