| 摘要 |
PURPOSE:To suppress haloing by forming a first blackened layer made of CuO and Cu2O, etching the layer to a predetermined thickness, and then further forming a second blackened layer enriched with the Cu2O by the second blackening. CONSTITUTION:When a circuit board for an inner layer is laminated, a circuit board for the layer which is previously degreased is first blackened to form a first blackened layer made of CuO and Cu2O, and the blackened layer is etched to a predetermined thickness. Further, a second blackened layer enriched with the Cu2O is formed by second blackening. That is, the formed blackened layer is etched until it is suitably reduced in thickness, and further the blackening is repeated. Thus, the blackened layer is enriched with the Cu2O, and the Cu2O enriched layer suppresses a haloing. |
