Abstract: A printed circuit device including semiconductor IC chips on the surface of a printed circuit board made of insulating material. The printed circuit board includes on the surface thereof semiconductor mounting regions and conductive layers. The semiconductor IC chips are respectively fixedly mounted on the semiconductor element mounting regions disposed on the printed circuit board. Thin metal wires interconnect electrodes of the IC chips with the conductive layers. A sealing cover plate having a plurality of recesses formed therein is fixedly mounted onto the surface of the printed circuit board with adhesive for hermetically sealing each of the IC chips and electric wires with a respective one of the recesses in the cover plate. The cover plate can comprise a composite of a thermoplastic resin material layer and a metal layer, such as aluminum or an aluminum alloy.

Abstract: An EPROM device having a hollow cap mounted on an insulating board covering an EPROM chip. The head portion of the hollow cap is made of material which passes UV rays therethrough. An UV ray transmitting resin fills at least a space between upper surface of the EPROM chip and an upper wall of the hollow cap and an injected resin fills the remaining spaces, so as to prevent the entry of moisture into the hollow cap.

Abstract: A heat-resistant plastic-packaged semiconductor device comprises an IC chip having contacts on its first surface, an island on which the IC chip is mounted with its second surface facing a first surface of the island, a low-adhesion layer which is formed on a second surface of the island, external leads, bonding wires for connection of the contacts on the IC chip and inner ends of the external leads, a package of mold resin for encapsulating the IC chip, the low-adhesion layer, the bonding wires and inner parts of the external leads, the mold resin being provided with a vent hole which extends to the vicinity of the low-adhesion layer. The low-adhesion layer has a low or no adhesive power to the mold resin.

Abstract: An EPROM device includes a hollow cap having a head portion made of a material which passes UV rays therethrough and is installed on a lead frame covering an EPROM chip. An UV ray permeable resin fills at least a gap between the head portion of the hollow cap and a main surface of the EPROM chip. A first insulating resin fills the remaining portion of the interior space of the hollow cap, thereby forming with the UV ray permeable resin a double filling structure filling the interior of the cap.

Abstract: A printed-circuit construction having an EPROM IC chip on the surface of an insulating baseboard. The insulating baseboard has on a primary surface a printed circuit pattern and a semiconductor chip support region. The EPROM IC chip is fixed to the semiconductor chip support region of the insulating baseboard. Thin metal wires connect electrodes of the EPROM IC chip to the printed circuit pattern. A cap is fixed to the primary surface of the insulating baseboard in covering relation to a surface of the EPROM IC chip and the thin metal wires. The cap is made of a material capable of transmitting ultraviolet radiation therethrough.