| 摘要 |
<p>PURPOSE:To obtain a small-sized high-density multilayered circuit board for electronic industries including high-frequency applications by forming heat- resistant surface layer portions in the whole of the board surface or in a part thereof on which a film-like passive element is disposed. CONSTITUTION:A multilayered circuit board which has a resistive conductor wiring 16 having a resistivity which does not exceed 5muOMEGA-cm in an inter-layer 22 formed by sequentially depositing insulating materials, and in which surface layer portions 21 and a film-like passive element 12 are disposed. The heat- resistant surface layer portions 21 are formed in the whole of the board surface or at least in a part thereof on which the film-like passive element 12 is disposed. This can prevent damage of the insulator around the board surface and the inner conductor wiring due to the thermal effect of a beam in trimming. Thus, a high-precision trimming is available and a low-resistance wiring including a high-precision film-like passive element can be provided, so that a multilayered circuit board of a smaller size and higher density can be achieved. Further, a high-speed and high-frequency signal can be provided.</p> |
