To achieve miniaturization. A matching circuit is connected to a connection terminal that is one of an input terminal and an output terminal of an amplifier. A mounting substrate has a ground layer. The matching circuit includes a main line, a sub-line, and an IC chip. The main line is formed of a first conductor pattern intersecting a thickness direction of the mounting substrate, and is connected to a connection terminal of the amplifier. The sub-line is formed of a second conductor pattern intersecting the thickness direction of the mounting substrate, and is connected between the main line and the ground layer. The sub-line is opposed to the main line in the thickness direction of the mounting substrate. The IC chip is disposed on the mounting substrate, and includes an adjustment unit that adjusts impedance conversion characteristics of the matching circuit.

An electronic element mounting substrate includes a first substrate that has a first main surface, has a rectangular shape, and has a mounting portion for an electronic element on the first main surface, and a second substrate that is located on a second main surface opposite to the first main surface, is made of a carbon material, has a rectangular shape, has a third main surface facing the second main surface and a fourth main surface opposite to the third main surface, in which the third main surface or the fourth main surface has heat conduction in a longitudinal direction greater than heat conduction in a direction perpendicular to the longitudinal direction, and that has a recessed portion on the fourth main surface.

In a semiconductor-mounting heat dissipation base plate including: an insulating substrate to which a metal circuit layer for mounting a semiconductor chip thereon is fixed; a heat dissipation base formed from the same metal material as the metal circuit layer at a side opposite to the metal circuit layer across the insulating substrate and fixed to the insulating substrate similar to the metal circuit layer; and a strengthening member provided in the heat dissipation base so as to be separated from the insulating substrate, the sizes of crystal grains of a metal structure at a part of the heat dissipation base or the metal circuit layer are reduced by a crystal size reducing material adhered to a mold, thereby preventing an adverse effect of a columnar crystal structure.

In a semiconductor-mounting heat dissipation base plate including: an insulating substrate to which a metal circuit layer for mounting a semiconductor chip thereon is fixed; a heat dissipation base formed from the same metal material as the metal circuit layer at a side opposite to the metal circuit layer across the insulating substrate and fixed to the insulating substrate similar to the metal circuit layer; and a strengthening member provided in the heat dissipation base so as to be separated from the insulating substrate, the sizes of crystal grains of a metal structure at a part of the heat dissipation base or the metal circuit layer are reduced by a crystal size reducing material adhered to a mold, thereby preventing an adverse effect of a columnar crystal structure.

A semiconductor element bonding substrate according to the present invention includes an insulating plate, and a metal pattern bonded to a main surface of the insulating plate. A main surface of the metal pattern on an opposite side of the insulating plate includes a bonding region to which a semiconductor element is bonded by a solder. The metal pattern includes at least one concave part located in the main surface. The at least one concave part is located closer to an edge of the bonding region in relation to a center part of the bonding region in the bonding region.

Provided is a semiconductor device having high planarity in an in-plane direction. This semiconductor device includes a semiconductor substrate, a first plating film pattern, a second plating film pattern, and an insulating layer. The semiconductor substrate has a first surface, and a second surface on a side opposite to the first surface. The first plating film pattern includes a first portion that covers a first regional portion of the first surface, and a second portion that is stacked to cover a portion of the first portion. The second plating film pattern includes a third portion that covers a second regional portion different from the first regional portion of the first surface, and also includes a fourth portion that is stacked to cover a portion of the third portion. A portion between the second portion and the fourth portion is filled with the insulating layer.

Provided is a semiconductor device having high planarity in an in-plane direction. This semiconductor device includes a semiconductor substrate, a first plating film pattern, a second plating film pattern, and an insulating layer. The semiconductor substrate has a first surface, and a second surface on a side opposite to the first surface. The first plating film pattern includes a first portion that covers a first regional portion of the first surface, and a second portion that is stacked to cover a portion of the first portion. The second plating film pattern includes a third portion that covers a second regional portion different from the first regional portion of the first surface, and also includes a fourth portion that is stacked to cover a portion of the third portion. A portion between the second portion and the fourth portion is filled with the insulating layer.

A high-frequency module includes: a chassis which is made of a conductor and which has an internal space; a high-frequency circuit board which is housed in the internal space of the chassis; and a resistive element provided between an inner wall that opposes the high-frequency circuit board among inner walls of the chassis which define the internal space and the high-frequency circuit board.

A semiconductor device includes a conductor, a semiconductor element, and a bonding layer. The conductor has obverse surfaces and reverse surfaces facing away from each other in a thickness direction. The semiconductor element has a body layer and electrodes projecting toward the obverse surfaces from a side of the body layer that opposes the obverse surfaces in the thickness direction. The bonding layer bonds the obverse surfaces and the electrodes. Each electrode has a base portion in contact with the body layer and a columnar portion projecting from the base portion and in contact with the bonding layer. The electrodes include a first electrode and a second electrode located closer to the periphery of the body layer than is the first electrode as viewed in the thickness direction. The second electrode is larger in area of the columnar portion than the first electrode, as viewed in the thickness direction.

An electronic device includes a component mounting portion, an electronic component disposed on the component mounting portion, a solder between the component mounting portion and the electronic component, a mounting base member, and a supporting beam connecting the component mounting portion and the mounting base member. The supporting beam has a plurality of bent portions. The supporting beam includes a frame, an outer supporting portion connecting the frame and the mounting base member, and an inner supporting portion connecting the frame and the component mounting portion. The inner supporting portion is shifted from the outer supporting portion along the frame. One of the plurality of bent portions is a connecting portion between the frame and the outer supporting portion. Another of the plurality of bent portions is a connecting portion between the frame and the inner supporting portion.