| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly reliable electronic device which has fine through electrodes, each of which has a desired minor diameter, even if a versatile insulation material is used in sealing an electronic component and enables further microfabrication.SOLUTION: An electronic component built-in substrate 20 includes: first insulation layers 4A, 4B (containing an inorganic filler 9a having a large diameter); electronic components 2A, 2B provided at the first insulation layers 4A, 4B; and through electrodes 8 penetrating through the first insulation layers 4A, 4B. A second insulation layer 6 (containing an inorganic filler 9b having a diameter smaller than that of the inorganic filler 9a) is embedded in first through holes 5 formed at the first insulation layers 4A, 4B, and second through holes 7, each of which has a diameter smaller than the first through hole 5, are formed at the second insulation layer 6. Then, conductive materials 8a, 8b are disposed in the second through holes. Through electrodes 8 are formed through these processes. |
