To achieve a good electrical connection between a contact pin and an external electrode while effectively suppressing the deformation of an external electrode such as a solder ball at the time of testing before packaging, by providing a test terminal adjacent to the external electrode.
An LSI chip 3 and a wiring layer 6 are electrically connected via a wire 4. The wiring layer 6 is extended to the reverse side of a substrate 7 via the inside of a through hole 8 from an area directly below a solder ball 10. An inner conductor 9 is formed so that it is surrounded by the wiring layer 6 in the through hole 8. A test terminal 11 is formed so that it is adjacent to the solder ball 10 and with an interval to the wiring layer on the main surface of the substrate 7. The solder ball 10 is extended between the inner conductor 9 and the wiring layer 6 and the test terminal 11, thus connecting the test terminal 11, the inner conductor 9, and the wiring layer 6 via the solder ball 10. As a result, when, for example, the solder ball 10 falls, a fault can be judged positively and an accurately test can be executed.
KURODA AKIHIRO
TOSA HIROAKI
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