| 摘要 |
<p>PROBLEM TO BE SOLVED: To increase reliability in bonding, even if there is a flip chip bond and a soldering bond in a wiring board by making a conductive hole for electrically connecting wiring layers and making the elasticity of an insulating layer in contact with the outermost wiring layer smaller than that of an insulating layer which is in contact with a wiring layer nearest an outermost wiring layer. SOLUTION: It is preferable for a highly dense multilayered wiring board that an interstitial via hole or an embedded via hole which connects only conductors between neighboring wiring layers be used. This multilayered wiring board has an insulating layer between the outermost wiring layer and a wiring layer nearest the outermost wiring layer. The insulating layer is made of two insulating layers whose elasticities are different from each other, and the elasticity of the insulating layer in contact with the outermost wiring layer is smaller than that of the insulating layer in contact with a wiring layer nearest the outermost wiring layer. An adhesive used for the insulating layer in contact with the wiring layer nearest the outermost wiring layer has an electrically insulating ceramic whisker as an essential component, and an adhesive made by mixing epoxy resin and a hardening agent thereof with a hardening promoting agent can be used.</p> |
