Abstract: A metal-based circuit board, which reduces the influence of thermal expansion, is provided having a structure where an insulating layer A having a large coefficient of thermal expansion is sandwiched between insulating layers B having a small coefficient of thermal expansion. Such a structure allows the insulating layers B to contract and expand so as to suppress contraction and expansion of the insulating layer A and thereby reduce the stress in the direction of negating the stress. As a result, while warpage or distortion is suppressed to be minimal, the bonding strength of the upper and the lower layer is maintained, and degree of freedom for circuit design is not impaired, thereby providing a highly reliable circuit structure.

Abstract: In a light emitting component, a resistor element is formed on the back surface of a substrate and its resistance value is adjusted to make the light intensity of a light emitting element (LED) in a predetermined range. A constant electric current circuit comprised of the resistor element and a transistor supplies the constant electric current to an LED, and the LED and the transistor are formed on a unit insulating substrate. In the case where the unit insulating substrate is rectangular in shape, one pair of opposite sides are x in length, the other pair of opposite sides are y in length and the ratio value of x/y is in the range of 1-1.25. Further, this light emitting component is provided with two resistor elements and both resistor elements are subjected to a resistor value adjustment.

Abstract: A metal-based circuit board, which reduces the influence of thermal expansion, is provided having a structure where an insulating layer A having a large coefficient of thermal expansion is sandwiched between insulating layers B having a small coefficient of thermal expansion. Such a structure allows the insulating layers B to contract and expand so as to suppress contraction and expansion of the insulating layer A and thereby reduce the stress in the direction of negating the stress. As a result, while warpage or distortion is suppressed to be minimal, the bonding strength of the upper and the lower layer is maintained, and degree of freedom for circuit design is not impaired, thereby providing a highly reliable circuit structure.

Abstract: In a light emitting component, a resistor element is formed on the back surface of a substrate and its resistance value is adjusted to make the light intensity of a light emitting element (LED) in a predetermined range. A constant electric current circuit comprised of the resistor element and a transistor supplies the constant electric current to an LED, and the LED and the transistor are formed on a unit insulating substrate. In the case where the unit insulating substrate is rectangular in shape, one pair of opposite sides are x in length, the other pair of opposite sides are y in length and the ratio value of x/y is in the range of 1-1.25. Further, this light emitting component is provided with two resistor elements and both resistor elements are subjected to a resistor value adjustment.

Abstract: An electronic component including, on one surface of a substrate (1), a plurality of circuit elements and external terminals each consisting of a conductive protrusion (9) for the circuit elements is provided with a structure capable of resisting an external force after mounting.

Abstract: A method for producing a flip-chip mounting electronic component having plural terminals (3) dotted on a mounting face (1) and conductors formed on the terminals (3) realizes flip-chip mounting capable of shortening the distance between bumps (7). To realize this, a step of coating the mounting face (1) with a conductor having a predetermined thickness, a step of masking corresponding positions for the terminal (3) parts on the conductor surface, and a step of removing the conductor except the mask (6) parts are included and performed in this order. The bump is preferably constituted of copper.

Abstract: A communication device capable of eliminating complexity of mounting a RFID part onto a commodity such as an electronic device. For this, the RFID part is fixed on an insulation substrate and the insulation substrate can be mounted on the surface of a circuit plate. Thus, the RFID part can be mounted onto a commodity by the technique of mounting on the general-purpose circuit plate. This significantly reduces the mounting work and achieves the object of the invention. The communication device may be such that the RFID part is fixed on a surface-mounted chip antenna and the RFID part has an antenna terminal electrically connected to a terminal of the surface-mounted chip antenna.