Method for manufacturing circuit board

1. A method for manufacturing a circuit board, the method comprising:

providing a circuit substrate comprising a substrate, a first inner circuit layer and a second inner circuit layer respectively arranged on opposite surfaces of the substrate and electrically coupled together, and forming a first insulating layer on a surface of the first inner circuit layer and an area of the substrate outside of the first inner circuit layer;

defining a first opening in the first insulating layer, the first opening penetrating the circuit substrate, and defining a second opening in the second inner circuit layer, the second opening penetrating the substrate;

arranging a first optical fiber in the first opening, the first optical fiber extending in a first direction, and arranging an optical component on the first insulating layer, the optical component electrically coupled to the first inner circuit layer and used for inputting an optical signal into the first optical fiber;

arranging an electronic component in the second opening, the electronic component electrically coupled to the second inner circuit layer;

forming a transparent insulating layer on a surface of the second inner circuit layer and the electronic component, forming a first inclined surface on the transparent insulating layer corresponding to the optical component, forming a second inclined surface on the transparent insulating layer corresponding to the electronic component, defining a groove extending to the first inclined surface and the second inclined surface, each of the first inclined surface and the second inclined surface forming an obtuse angle with a bottom surface of the groove; and

arranging a second optical fiber in the groove, arranging a first reflective layer and a second reflective layer respectively on a surface of the first inclined surface and the second inclined surface away from the second optical fiber, the first reflective layer, the second optical fiber, and the second reflective layer cooperatively forming an optical channel, the optical channel used for realizing optical signal transmission between the optical component and the electronic component.

2. The method of claim 1 , further comprising:

defining a third opening opposite corresponding to the second opening in the first insulating layer; and

forming a heat dissipation block in the third opening, wherein the heat dissipation block is in contact with the first inner circuit layer.

3. The method of claim 1 , wherein:

a shielding layer is formed on a side of the first reflective layer, the second reflective layer, and the second optical fiber away from the electronic component.

4. The method of claim 1 , further comprising:

forming a second insulating layer and an outer circuit layer on a surface of the transparent insulating layer and the second optical fiber, wherein the outer circuit layer is electrically coupled to the second inner circuit layer.

5. The method of claim 1 , further comprising:

defining a first blind hole and a second blind hole in the transparent insulating layer, wherein:

an inner wall of the first blind hole comprises the first inclined surface; and

an inner wall of the second blind hole comprises the second inclined surface.

6. The method of claim 1 , wherein:

a plurality of solder pads is provided on the first inner circuit layer;

the solder pads are not covered by the first insulating layer; and

the optical component is electrically coupled to the first inner circuit layer through the solder pads.

7. The method of claim 1 , further comprising:

forming a third inner circuit layer on the bottom surface of the groove; wherein:

the third inner circuit layer is electrically coupled to the second inner circuit layer and the electronic component.