Abstract: A semiconductor device having a large on-state current and high reliability is provided. The semiconductor device includes a first insulator, a first oxide over the first insulator, a second oxide over the first oxide, a third oxide and a fourth oxide over the second oxide, a first conductor over the third oxide, a second conductor over the fourth oxide, a fifth oxide over the second oxide, a second insulator over the fifth oxide, and a third conductor over the second insulator. The fifth oxide is in contact with a top surface of the second oxide, a side surface of the first conductor, a side surface of the second conductor, a side surface of the third oxide, and a side surface of the fourth oxide. The second oxide contains In, an element M, and Zn. The first oxide and the fifth oxide each contain at least one of constituent elements included in the second oxide. The third oxide and the fourth oxide each contain the element M.

Abstract: An opto-electric hybrid board includes: an electric circuit board including an insulative layer, and an element mounting electrode formed on the front surface of the insulative layer; an optical element mounted on the element mounting electrode by contact frictional heat; and an optical waveguide including a first cladding layer in contact with the back surface of the insulative layer of the electric circuit board. Between the insulative layer and the first cladding layer, a reinforcing layer is provided at the portion corresponding to the element mounting electrode. A reinforcing layer is provided at the portion corresponding to the element mounting electrode, in the surface of the first cladding layer, which is on the side opposite to the insulative layer. The resin-made reinforcing layer is greater than the first cladding layer in storage modulus at the temperature of the board when the element is being mounted.

Abstract: An opto-electric hybrid board which is capable of significantly reducing stresses applied to a bent portion thereof is provided. The opto-electric hybrid board includes a stacked electric circuit board and an optical waveguide. The electric circuit board includes an insulative layer having front and back surfaces, electrical interconnect lines formed on the front surface of the insulative layer, and an insulative coverlay formed on the front surface of the insulative layer and for covering and protecting the electrical interconnect lines. The optical waveguide includes a first cladding layer having a front surface, cores formed in a pattern on the front surface of the first cladding layer, and a second cladding layer covering the cores. Part of the opto-electric hybrid board is defined as a to-be-bent portion in which the coverlay and the optical waveguide are disposed in non-overlapping relation.

Abstract: An opto-electric hybrid board includes: an electric circuit board including an insulative layer, and an element mounting electrode formed on the front surface of the insulative layer; an optical element mounted on the element mounting electrode by contact frictional heat; and an optical waveguide including a first cladding layer in contact with the back surface of the insulative layer of the electric circuit board. Between the insulative layer and the first cladding layer, a reinforcing layer is provided at the portion corresponding to the element mounting electrode. A reinforcing layer is provided at the portion corresponding to the element mounting electrode, in the surface of the first cladding layer, which is on the side opposite to the insulative layer. The resin-made reinforcing layer is greater than the first cladding layer in storage modulus at the temperature of the board when the element is being mounted.

Abstract: An opto-electric hybrid board which is capable of significantly reducing stresses applied to a bent portion thereof is provided. The opto-electric hybrid board includes a stacked electric circuit board and an optical waveguide. The electric circuit board includes an insulative layer having front and back surfaces, electrical interconnect lines formed on the front surface of the insulative layer, and an insulative coverlay formed on the front surface of the insulative layer and for covering and protecting the electrical interconnect lines. The optical waveguide includes a first cladding layer having a front surface, cores formed in a pattern on the front surface of the first cladding layer, and a second cladding layer covering the cores. Part of the opto-electric hybrid board is defined as a to-be-bent portion in which the coverlay and the optical waveguide are disposed in non-overlapping relation.

Abstract: A photosensitive resin composition is provided, which has properties necessary for a solder resist (insulative property, solder heat resistance, alkali developability and the like) and is capable of forming a film that is excellent in folding endurance even after the IR reflow process. A flexible circuit board employing the photosensitive resin composition and a circuit board production method are also provided. The photosensitive resin composition comprises: (A) a linear polymer of an ethylenically unsaturated compound comprising a carboxyl-containing ethylenically unsaturated compound; (B) an epoxy resin; (C) a polymerizable compound containing an ethylenically unsaturated group; and (D) a photopolymerization initiator. The photosensitive resin composition has a tensile breaking elongation percentage of not less than 10% and a 2% weight loss temperature of not lower than 260° C. after being cured.

Abstract: A halogen-free and flame-resistant photosensitive resin composition is provided, which has properties necessary for a solder resist (insulative property, solder heat resistance, alkali developability and the like) and is capable of forming a film that is excellent in folding endurance even after an IR reflow process. A flexible circuit board employing the photosensitive resin composition and a circuit board production method are also provided.

Abstract: A halogen-free and flame-resistant photosensitive resin composition is provided, which has properties necessary for a solder resist (insulative property, solder heat resistance, alkali developability and the like) and is capable of forming a film that is excellent in folding endurance even after an IR reflow process. A flexible circuit board employing the photosensitive resin composition and a circuit board production method are also provided.

Abstract: A halogen-free and flame-resistant photosensitive resin composition is provided, which has properties necessary for a solder resist (insulative property, solder heat resistance, alkali developability and the like) and is capable of forming a film that is excellent in folding endurance even after an IR reflow process. A flexible circuit board employing the photosensitive resin composition and a circuit board production method are also provided.

Abstract: A photosensitive resin composition is provided, which has properties necessary for a solder resist (insulative property, solder heat resistance, alkali developability and the like) and is capable of forming a film that is excellent in folding endurance even after the IR reflow process. A flexible circuit board employing the photosensitive resin composition and a circuit board production method are also provided. The photosensitive resin composition comprises: (A) a linear polymer of an ethylenically unsaturated compound comprising a carboxyl-containing ethylenically unsaturated compound; (B) an epoxy resin; (C) a polymerizable compound containing an ethylenically unsaturated group; and (D) a photopolymerization initiator. The photosensitive resin composition has a tensile breaking elongation percentage of not less than 10% and a 2% weight loss temperature of not lower than 260° C. after being cured.

Abstract: A printing apparatus includes a feed-out unit for feeding out an elongated base material which is wound up in a roll, a printing unit for printing a liquid resist onto the elongated base material that is fed out of the feed-out unit, a wind-up unit for winding up the elongated base material on which the liquid resist is printed by the printing unit into a roll, and a suction unit positioned between the printing unit and the wind-up unit in a transport direction of the elongated base material for sucking up a solvent in the liquid resist.

Abstract: A printing apparatus includes a feed-out unit for feeding out an elongated base material which is wound up in a roll, a printing unit for printing a liquid resist onto the elongated base material that is fed out of the feed-out unit, a wind-up unit for winding up the elongated base material on which the liquid resist is printed by the printing unit into a roll, and a suction unit positioned between the printing unit and the wind-up unit in a transport direction of the elongated base material for sucking up a solvent in the liquid resist.

Abstract: A wired circuit board which is formed so that even when a wired circuit pattern is formed at a fine pitch and then a tin plating layer is formed on the wired circuit pattern by the electroless tin plating, a wiring of the wired circuit pattern can be prevented from being stripped, and a production method of the same wired circuit board. After a thin metal film 2 formed of nickel-chromium alloy having a chromium content of 8-20 weight % is formed on an insulating layer 1, a wired circuit pattern 4 of copper is formed on the thin metal film 2. Then, a tin plating layer 5 is formed on exposed surfaces of the wired circuit pattern 4 by electroless tin plating.

Abstract: A method of producing a multilayer wired circuit board that can suppress making gouge in an adhesive layer when a hole is formed by irradiation with a laser beam, to provide a smoothened inside surface of the hole so as to provide enhanced reliability of electrical connection. A first substrate 4 having the structure wherein a first metal foil 2 and a second metal foil 3 are formed on both sides of a first insulating layer 1 and a second substrate 7 having the structure wherein a third metal foil 6 is formed on a single side of a second insulating layer 5 are prepared, separately. Then, the first metal foil 2 of the first substrate 4 and the second insulating layer 5 of the second substrate 7 are bonded together through an adhesive layer 8. Thereafter, the resultant laminate is irradiated with a laser beam emitting from the first substrate 4 side toward the second substrate 7 side, to form a through hole 9.

Abstract: A probe structure containing a contact part (2) formed on one side (1a) of an insulating substrate (1), a conductive circuit (3) formed on the other side (1b) of the insulating substrate (1), wherein the contact part (2) and the conductive circuit (3) are connected via a conductive path (5) formed in a through-hole (4) in the thickness direction of the insulating substrate (1). The contact part (2) has a structure containing a deep layer (1c) having a hardness of 100-700 Hk, an intermediate layer (1b) having a hardness of 10-300 Hk, and a surface layer (1a) having a hardness of 700-1200 Hk successively laminated. The surface layer (1a) preferably has a tensile stress of not more than 50 kg/mm.sup.2. The probe structure maintains low and stable contact resistance in an electric test, in particular a burn-in test, of small test objects such as IC.