| 摘要 |
<p>PURPOSE:To obtain the semiconductor device to radiate heat favorably by a method wherein an insulating substrate consisting of mainly non-oxide ceramics and having the coefficient of thermal expansion nearly the same with Si, and moreover having thermal conductivity of 0.2cal/sec.cm deg.C or more is used, a semiconductor element is fixed thereto, the element and isolated outside leads are connected, and the device is sealed airtightly with a ceramic cover. CONSTITUTION:A sintered body of SiC ceramics having theoretical density of 98% and consisting of 2wt% BeO and the remnant of SiC and impurities mixed inevitably is used as the substrate 1. SiC thereof indicates specific gravity of about 3.2, resistivity of 10<13>OMEGAcm, the coefficient of thermal expansion (at room temperature-900 deg.C) of about 40X10<-7>/ deg.C, heat conductivity (at the room temperature) of 0.6cal/sec.cm deg.C and bending strength of 45kg/mm.<2>. The element 2 is soldered 3 onto the substrate, the leads 4 are adhered with glass 5, connection 6 is performed and the device is sealed with glass 8 using an alumina cover 7. According to use of the SiC ceramics thereof, heat resistance is reduced sharply, a distortion buffer material of Mo, etc., to be placed between the element and the substrate becomes as needless according to approximation of the coefficients of thermal expansion of both to reduce weight, and the device is also advantageous economically.</p> |
