Abstract: Disclosed is a high breakdown voltage semiconductor device comprising a semiconductor substrate, an active layer consisting of a high resistivity semiconductor layer of a first conductivity type formed on the substrate with an insulating layer interposed therebetween, a first impurity region of the first conductivity type formed within the active layer, a second impurity region of a second conductivity type formed within the active layer, a third impurity region of the second conductivity type formed within the second impurity region and having a high impurity concentration, a first electrode being in ohmic contact with the first impurity region and the fourth impurity region, and a second electrode being in Schottky contact with the second impurity region and in ohmic contact with the third impurity region.

Abstract: Disclosed is a high breakdown voltage semiconductor device comprising a semiconductor substrate, an active layer consisting of a high resistivity semiconductor layer of a first conductivity type formed on the substrate with an insulating layer interposed therebetween, a first impurity region of the first conductivity type formed within the active layer, a second impurity region of a second conductivity type formed within the active layer, a third impurity region of the second conductivity type formed within the second impurity region and having a high impurity concentration, a first electrode being in ohmic contact with the first impurity region and the fourth impurity region, and a second electrode being in Schottky contact with the second impurity region and in ohmic contact with the third impurity region.

Abstract: Disclosed herein is a photosensitive solder resist ink capable of development with a dilute alkaline solution. It has a wide pre-curing latitude. It permits the pre-cured board to be stored for a long period of time. It is superior in resolution, sensitivity, and solder resistance. Disclosed also herein is a printed circuit board having good adhesion, chemical resistance, electrical properties, gold plating resistance, solder heat resistance, and electrocorrosion resistance. Disclosed also herein is a process for producing said printed circuit board by using said solder resist ink.The photosensitive solder resist ink comprises (A) an ultraviolet-curable resin containing 0-20 wt % of aromatic ring moiety which is obtained by reacting a polymer composed of (a) 40-100 mol % of ethylenically unsaturated monomer having an epoxy group and (b) 0-60 mol % of ethylenically unsaturated monomer capable of copolymerization therewith, with (meth)acrylic acid in an amount of 0.7-1.