| 摘要 |
PROBLEM TO BE SOLVED: To hold favorably the adhesion of the contact surface of a packaged semiconductor device with a printed wiring board by a method wherein a standoff is formed in the mounting surface of the device for coming into contact with the mounting surface of the board, and a gap is formed between the mounting surface of the board and the mounting surface of the device. SOLUTION: A standoff 15 formed with a recessed part is provided in the lower surface 14 of a packaged semiconductor device 10, and the standoff 15 is formed in the sides of leads 20 on the lower surface 14 of the device 10. A space is formed in the part of the standoff 15 between the device 10 and a printed wiring board, that is, the mounting surface of the board is provided in such a way as to contact with one part of the lower surface 14 excluding the standoff 15. As a result, even though dusts enter inside between the device 10 and the board, the device 10 is never raised from the board and is never slanted from the board, and the promotion of efficiency of a soldering work of the leads to the device 10 can be contrived. |
