| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-reliability wiring substrate with reduced possibility of wire fracture, even if thermal stress is generated between an insulating resin layer and a ceramic wiring substrate. SOLUTION: This wiring substrate is provided with a ceramic wiring substrate 1, a plurality of insulating resin layers 2 laminated on the upper surface of the ceramic wiring substrate 1, a plurality of wiring layers 3 on the upper surface of the respective insulating resin layers 2, via conductors 4 that connects wiring layers 3, 3 disposed on the upper side and lower side of the insulating resin layer 2, and a through conductor 6 that reaches the upper surface of the lowest layer of the insulating resin layer 2 from within the ceramic wiring substrate 1 and connects the internal wiring 5 of the ceramic wiring substrate 1 with the wiring layer 3 of the upper surface of the lowest layer of the insulating resin layer 2. Since there is no connection portion of the via conductor 4 with comparatively weak connecting strength in the interface between the ceramic wiring substrate 1 and the lowest layer of the insulating resin layer 2, whose thermal stress tends to increase, the possibility of wire fracture is reduced. Therefore, a high-reliability wiring substrate can be provided. COPYRIGHT: (C)2010,JPO&INPIT |
