Patent ID: 11937377
Assignee: SHENNAN CIRCUITS CO., LTD.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 14:
15. A circuit board preparation method, comprising:
providing a copper-clad plate, wherein the copper-clad plate comprises an insulating layer, a first copper layer arranged on a first surface of the insulating layer, and a second copper layer arranged on a second surface of the insulating layer and opposite to the first copper layer; defining at least one hole at a set position of the copper-clad plate, wherein each of the at least one hole comprises a micro-blind hole and/or a through hole, and the at least one hole penetrates the insulating layer; and hole-treating the at least one hole;
applying a first photosensitive film on a surface of the first copper layer and a surface of the second copper layer, respectively; leaving a first predetermined position on the first photosensitive film exposed; performing hole-filling plating for the first predetermined position to form a first tab at the first predetermined position; and removing the first photosensitive film from the copper-clad plate;
attaching a second photosensitive film to a second predetermined position of the copper-clad plate, and etching the copper-clad plate to form a conductive line on the to-be-treated plate; removing the second photosensitive film on the to-be-treated plate to obtain a to-be-processed plate; wherein the second predetermined position is a position at which a conductive line is not planned to be arranged; wherein the to-be-processed plate comprises an insulating layer, a first copper layer arranged on a first surface of the insulating layer, a second copper layer arranged on a second surface of the insulating layer and opposite to the first copper layer, a blind metalized hole, and a first tab arranged on the first surface and facing the blind metalized hole;
obtaining a white insulating material; laminating the white insulating material to a surface of the insulating layer, a surface of the first copper layer, a surface of the first tab, and a surface of the second copper layer to form a first white insulating medium layer on a surface of the to-be-processed plate and a second white insulating medium layer on another surface of the to-be-processed plate opposite to the first while insulating medium layer; and
performing surface polishing for the first white insulating medium layer and grinding the first white insulating medium layer until the first tab is exposed to form a first white reflective layer.