| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce stress on solder by decreasing the difference of an expansion/contraction degree between a circuit substrate and an electronic component joined to the circuit substrate by soldering, in an electronic device mounted with the electronic component on the circuit substrate by soldering. <P>SOLUTION: A circuit substrate 10 has a linear expansion coefficient larger than that of an electronic component 20. The electronic component 20 is fixed to the circuit substrate 10 at a first electrode 21 and a second electrode 22 through solder 30. A part 13 between fixed portions which is a part positioned between a fixed portion of the first electrode 21 and a fixed portion of the second electrode 22 of the circuit substrate 10 is provided with trough-holes 14 on one surface 11. Therefore, a degree of thermal expansion and thermal contraction of the part 13 between the fixed portions is smaller than that of a part except for the part 13 between the fixed portions of the circuit substrate 10. <P>COPYRIGHT: (C)2012,JPO&INPIT |
