| 摘要 |
<p>PURPOSE:To obtain the multilayer hybrid IC by a method wherein resistors are formed in a multilayer type on a substrate making a laser resisting protective resin layer as the interlayer insulating film, and laser trimming is performed. CONSTITUTION:Copper foils 2 of the desired pattern are provided on the substrate 1, and a resist mask is printed to form the Ni plating resistors 3. Then BN, Al2O3, etc., are mixed to epoxy resin 4 and is controlled to have permeability of 50% or less to laser, and the part other than connecting holes 5 with copper foils 2 and the fixing part of a circuit element 8 is silk screened. Then electrically conducting paths 6 according to electroless Ni plating, for example, are provided to be connected to foils 2, carbon resistive paint is printed and baked to provide the resistors 7, and laser trimming is performed to regulate to have the desired resistance value. At this time, although the laser beam cut off the resistors 7, it is scattered by the resin layers 4, and insulation between the resistors 3 of the lower layer and copper foils 2 is held favorably. According to this construction, formation of the hybrid IC in a small type can be attained.</p> |
