Abstract: A method of photodelineating an adhesive on a substrate. The first step (10) is to coat the substrate with a layer of photopolymeric adhesive, typically spin coated. The adhesive is then briefly `soft baked` at a moderate temperature to set it (20). Portions of the adhesive are then selectively exposed to actinic radiation to partially cure them, while other portions are not exposed (30). A photomask is used to selectively expose the photopolymeric adhesive to ultraviolet light at an intensity and for a time sufficient to partially cure the photopolymeric adhesive. The adhesive is developed (40) to selectively remove those portions that were not exposed to radiation, usually in an appropriate solvent, creating a pattern in the adhesive. The developed adhesive pattern is then heated for a time and temperature sufficient to completely cure it (50).

Abstract: A shielded, erasable-programmable-read-only-memory (EPROM) package is provided. A circuit carrying substrate (10), contains an area for mounting an EPROM chip (16), having conductive interconnecting patterns (12) adjacent to the chip mounting area. The EPROM chip is mounted on the circuit carrying substrate, and the pad electrodes on the EPROM chip are connected to pads on the conductive patterns of the substrate by wire bonds (17) or other means. An ultraviolet (UV) light transmitting resin (18) is transfer molded onto the circuit carrying substrate, covering the EPROM chip (16) and the wire bonds (17) so as to provide an optical path through the material to the top surface of the EPROM chip, and sealing the EPROM chip from the exterior of the package. An adherent metal coating (19) is sputtered over the transfer molded resin, and the metal coating is coated with a protective organic resin (15). Both the metal coating and the organic resin are at least partially transparent to ultraviolet light.

Abstract: A process for manufacturing a substrate (12) used in a device (10) for containing a liquid crystal fluid (30) between two spaced electrodes. A plurality of spacers (35) is distributed on a first surface of a substrate by coating the first surface with an admixture of spacers dispersed in a liquid (36). The admixture is agitated during the applications step in order to maintain a uniform dispersion of the spacers in the liquid. The liquid is then evaporated from the substrate surface, leaving a plurality of spacers distributed on the substrate. Preferably, an ester alcohol dispersant is employed in the admixture in order to facilitate dispersion of the spacers in the liquid. Ultrasonics are preferred as the means of agitating the admixture during application. Ultrasonic energy can also be applied to the substrate during application of the admixture to the substrate. Ultrasonic energy can also be applied to the admixture at the point of application (44) of the admixture onto the substrate.

Abstract: Photoreactive polymers are treated by exposure to microwave energy. A film of a photoreactive polymer (12), such as a photoresist, is applied to a substrate (10) and selectively exposed to ultraviolet light. The latent image produced is further cured or polymerized by treating the photoresist with microwave energy. Combinations of microwave and thermal energies are also used. The treated photoresist is then developed, producing a sidewall (17) that is vertical, and is improved by reduction of anomolies such as scum or a foot (16) at the base of the resist.

Abstract: A partially overmolded integrated circuit package (10) comprises a substrate (14) having circuit traces (11) and a semiconductor die receiving area (15) for attachment of a semiconductor die to the semiconductor die receiving area. Conductive bumps (18) are then applied to a plurality of contact pads on the semiconductor die. Then overmolding compound (16) is applied over the semiconductor die and a portion of the conductive bumps, leaving a portion of the conductive bumps partially exposed (19). Finally, interconnections (13) between the exposed portion of the conductive bumps and the circuit traces of the substrate are formed.

Abstract: A method of metallizing a substrate by vacuum depositing a thin layer of chromium. The substrate is first cleaned (16) by exposing it to a plasma gas discharge. A thin layer of chromium metal is then sputtered under vacuum (17) onto the substrate. The substrate is then heated in an oxygen containing atmosphere (18) for a period of time and at a temperature sufficient to convert the chromium metal to chromium oxide. A second layer of chromium metal is then sputtered (20) onto the chromium oxide layer in order to form an adherent metal system to the substrate.

Abstract: A transfer molded pad array chip carrier is formed by mounting and wirebonding a semiconductor device (12) on a printed circuit board (10). The bottom side of the printed circuit board may have an array of solderable surfaces (24). A polymer coating (18) is applied over the semiconductor device (12), the wirebonds (16), and the top side of the printed circuit board (10) and cured. The coating (18) is then sputter etched in a partial vacuum to enhance the adhesion of the transfer molding compound (20) to the printed circuit board (10). The semiconductor device is encapsulated by a transfer molding process. The polymer coating (18) also provides a barrier to alpha particle emission, improves the moisture resistance of the completed package and reduces stress at the surface of the device.