| 摘要 |
1465650 Semi-conductor devices SIEMENS AG 24 Dec 1974 [14 Jan 1974] 55771/74 Heading H1K A semi-conductor device 1 has a permanent protective insulating coating comprising a photo-sensitive resin hardened by heat treatment. The resin may be a positive photo-resist, e.g. a diazo type resin, or negative, e.g. polyvinyl esters such as polyvinylcinnamate, or cyclized isoprene polymers, or a combination of the two. The resin may or may not have functioned as a mask for etching or metal deposition during manufacture of the device. As shown layer 14 encloses the device completely except for apertures for connections 11, 12, 13 to the collector, base and emitter respectively of the transistor illustrated, and is applied over an intervening silica or silicon nitride layer 4. The heat treatment preferably comprises the conventional hardening step, then heating at 100‹ to 210‹ C. for 5 mins. to 1 hour, then at 190‹ to 300‹ C. for 5 to 30 minutes. The resin may include heat conductive fillers, e.g. MgO, SiO 2 or Al 2 O 3 ,to aid heat dissipation particularly when the device is enclosed in a metal container. The device may alternatively be a diode, thyristor or integrated circuit and may be formed by subdivision of a plurality of devices, with further encapsulation to cover thus exposed surfaces. |
