| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a high-reliability semiconductor device by preventing increase of thermal resistance due to thermal fatigue of upper and lower solder layers of a semiconductor chip when a lead frame is used for wiring of the semiconductor chip. <P>SOLUTION: Semiconductor chips 5 and lead frames 7 are fixed on a copper-based substrate 3 in a case 9 and on the semiconductor chips 5 with solder layers 4, 6, respectively, and they are covered with double-layer sealing material layers 12, 13. The entire semiconductor chips 5, partial parts of the lead frames 7 being wires and the copper-based substrate 3 around the semiconductor chips 5 are covered with the first sealing material layers 12; the outer side thereof is covered with the second sealing material layer 13; the coefficient of thermal expansion of the first sealing material layer 12 is set to 1.5×10<SP>-5</SP>/°C to 1.8×10<SP>-5</SP>/°C in the vicinity of that of the copper-based substrate 3; joint strength of the first sealing material layer 12 to the copper-based substrate 3 is set to 15-30 MPa; and thereby this high-reliability semiconductor device can be provided by preventing increase of thermal resistance due to thermal fatigue of the upper and lower solder layers 4, 6 of the semiconductor chips 5. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
