A kind of manufacture method of printed circuit board (PCB)
Technical field
The present invention relates to a kind of manufacture method of printed circuit board (PCB), relate in particular to a kind of copper window preparation technology who carries out printed circuit board (PCB) with the laser contraposition.
The background skill is not
Printed circuit board (PCB) is with copper foil circuit complicated between part and the part, and system is put in order on a plank, so that the main support body of electronics spare part when installing with interconnection to be provided, is the indispensable fundamental parts of all electronic products.
Because the circuit of printed circuit board (PCB) is got over complicated, high density interconnect (High Density Interconnection, HDI) technology is arisen at the historic moment, it is additionally to increase layer outside circuit board, and produce the inter-level interconnects of non-machine drill Microvia (Microvia, aperture 6mil following) in the mode of laser drill.
Common prior art is to open the copper window earlier on the copper layer to carry out laser drill again, and the print circuit plates making flow process of prior art as shown in Figure 1 to Figure 3.
Please refer to Fig. 1, at first, provide two preimpregnation material (Prepreg) 10a and 10b as insulative core layer (core layer), and in regular turn copper layer 14a, dielectric layer 12a, preimpregnation material 10a, dielectric layer 12c, preimpregnation material 10b, dielectric layer 12b, copper layer 14b are pressed together, form the structure of printed circuit board (PCB) 100, wherein preimpregnation material surface 17a and 17b have copper foil circuit pattern 16a, 16b and aligned pattern 18a, 18b respectively.
Then, as shown in Figure 2, by the calculating of computer to the pressing error, calculate aligned pattern 18a among Fig. 1 and the relative position of 18b and copper foil circuit pattern 16a and 16b, and go out a mask (not shown) with this data creating and expose again and etching, in copper layer 14a and 14b, leave opening 22a and 22b respectively, and opening 22a and 22b are positioned at the top of copper foil circuit pattern 16a and 16b.
As shown in Figure 3, remove the dielectric layer 12a and the 12b of opening 22a and 22b top with laser beam, form copper window 32a and 32b, copper window 32a and 32b make copper foil circuit pattern 16a and 16b come out, make copper foil circuit pattern 16a and 16b can by after chemical copper deposition and technology such as electro-coppering form electrical connection again.
In the prior art, owing to must use the mode of estimation, aligned pattern 18a that supposition copper layer 14a and 14b and dielectric layer 12a and 12b are covered and the position of 18b and copper foil circuit pattern 16a and 16b, so the position of the copper window 32a that leaves and 32b common and real copper foil circuit pattern 16a and 16b has bigger error, there is time error also may reach about 7mil, therefore how to increase the contraposition precision of copper window technology, and the ability of lifting live width/line-spacing (line/space) is the task of top priority of this area really.
Summary of the invention
The invention provides a kind of manufacture method of printed circuit board (PCB) of improvement, to address the above problem.
In the most preferred embodiment of the present invention, provide a kind of manufacture method of printed circuit board (PCB), this method comprises:
The insulative core layer is provided, and this insulative core laminar surface comprises copper foil circuit pattern and aligned pattern, and dielectric layer is covered on insulative core layer and copper foil circuit pattern and the aligned pattern, and the copper layer is covered on the dielectric layer;
Remove the copper layer; And
Light beam is provided, scans out aligned pattern to orient the copper foil circuit pattern and to remove the dielectric layer of the copper foil circuit pattern top of orienting, to form opening.
Described insulative core layer comprises at least one Copper Foil basal plate, and described dielectric layer comprises preimpregnation material or gum Copper Foil.
Described light beam is a laser beam.
It is when arriving the aligned pattern of described insulative core laminar surface by described laser beam irradiation, can find out aberration on the supervision screen of board that laser beam scans out described aligned pattern, differentiates described aligned pattern position thus.
Removing the copper layer is to utilize an etching technics.
Described opening is to form by the described dielectric layer that laser drilling process is removed the described copper foil circuit top orient, the dual-side of opening by dielectric layer constitute, the base of opening is made of the copper foil circuit pattern.
This method is further comprising the steps of after forming described opening:
After laser drilling process, provide a surface coarsening technology, in order to increase the roughness on described dielectric layer surface, described opening dual-side surface and described open lower side surface;
Carry out a chemical copper depositing operation, form a chemical copper in described dielectric layer surface, described opening dual-side surface and this open lower side surface; And
Utilize an electroplating technology, in order to form a copper electroplating layer in described chemical copper surface.
Also comprise: form a photoresist pattern on described chemical copper surface before electroplating technology, described electroplating technology can not form described copper electroplating layer on described photoresist pattern.
Also comprise: the technology of carrying out removing photoresist after described copper electroplating layer forms is to remove described photoresist pattern.
The present invention also provides a kind of manufacture method of printed circuit board (PCB), and this method comprises:
One force fit plate is provided, it is to be formed by one first bronze medal layer, one first dielectric layer, one first insulative core layer, one second dielectric layer, one second insulative core layer, one the 3rd dielectric layer and one second bronze medal layer pressing in regular turn, have one first copper foil circuit pattern and one first aligned pattern between first dielectric layer and the first insulative core layer, have one second copper foil circuit pattern and one second aligned pattern between the 3rd dielectric layer and the second insulative core layer;
Remove described first bronze medal layer and the described second bronze medal layer;
Provide a laser beam to scan the aberration that described force fit plate is manifested by described first aligned pattern and described second aligned pattern, determine the position of described first aligned pattern and described second aligned pattern, to orient the described first copper foil circuit pattern and the second copper foil circuit pattern; And the described dielectric layer of removing described described first copper foil circuit pattern of orienting and second copper foil circuit pattern top, to form an opening.
Removing the described first bronze medal layer and the second bronze medal layer is to utilize an etching technics.
Described method includes following steps after forming described opening:
Provide a surface coarsening technology after the laser drilling process that forms described opening, in order to increase the roughness of described first dielectric layer and described the 3rd dielectric layer surface and described open surfaces;
Carry out a chemical copper depositing operation, form a chemical copper in described first dielectric layer and the 3rd dielectric layer surface and described open surfaces; And
Utilize an electroplating technology, in order to form a copper electroplating layer in described chemical copper surface.
Also comprise: form a photoresist pattern in described chemical copper surface before electroplating technology, described electroplating technology can not form described copper electroplating layer on described photoresist pattern.
Also comprise: the technology of carrying out removing photoresist after described copper electroplating layer forms is to remove described photoresist pattern.
Among the present invention because utilize etching technics to remove earlier on the copper layer, and directly utilize laser beam to find out the position of Copper Foil, so the present invention need not utilize mask definition copper window, so effectively increase the contraposition ability of laser drill, the ability of lifting live width/line-spacing (line/space), and technology is shortened, and cost descends, and efficiently solves the shortcoming of prior art.
Description of drawings
Fig. 1 to Fig. 3 is the print circuit plates making schematic flow sheet of prior art;
Fig. 4 to Fig. 9 is a print circuit plates making schematic flow sheet of the present invention.
Embodiment
Please refer to Fig. 4 to Fig. 9, Fig. 4 to Fig. 9 is printed circuit board (PCB) of the present invention (PCB) manufacture method schematic diagram.
Please refer to Fig. 4, at first, with pressing dielectric layer 42c between two insulative core layers (core layer) 40a and the 40b, can be the interconnect circuit between insulative core layer 40a, 40b and the dielectric layer 42c wherein, insulative core layer 40a, 40b have formed the Copper Foil basal plate of interconnect circuit by the number laminar surfaces (Copper Clad Laminate, CCL) pressing have formed.Dielectric layer 42c can be as material with preimpregnation material (Prepreg).All have copper foil circuit pattern 46a, 46b and aligned pattern 48a, 48b on surperficial 47a, the 47b of insulative core layer 40a, 40b.Then dielectric layer 42a is pressed on the surface of insulative core layer 40a, copper foil circuit pattern 46a and aligned pattern 48a, copper layer 44a is pressed on the dielectric layer 42a again, and insulative core layer 40b be also as insulative core layer 40a, and its surface is pressing dielectric layer 42b and copper layer 44b in regular turn.At last, this force fit plate forms the structure of printed circuit board (PCB) 400.Wherein, dielectric layer 42a, 42b are not limited in preimpregnation material (Prepreg) as material.Another embodiment of the present invention then forms for dielectric layer 42a, 42b adopt gum Copper Foil (RCC) pressing, and just do not need to implement in addition pressing working procedure with pressing copper layer 44a, 44b this moment again.
As shown in Figure 5, the present invention utilizes copper layer 44a and the 44b among wet etching technics removal Fig. 4 earlier, the purpose of this etching technics increases the adhesion of subsequent chemistry copper layer and dielectric layer 42a, 42b making dielectric layer 42a, 42b surface become more coarse after removing copper layer 44a and 44b.Then, utilize a laser beam to scan printed circuit board (PCB) 400 again, when laser beam irradiation arrives surperficial 47a, 47b, can find out that on the supervision screen of board aligned pattern 48a, 48b can demonstrate aberration, therefore can calculate the position of aligned pattern 48a and 48b according to this, in like manner, the position of copper foil circuit pattern 46a, 46b be can calculate, copper foil circuit pattern 46a, 46b oriented thus by the relative position of aligned pattern 48a, 48b and copper foil circuit pattern 46a, 46b.
Please refer to Fig. 6, after determining copper foil circuit pattern 46a, 46b position, impose laser drilling process again, remove dielectric layer 42a, the 42b of copper foil circuit pattern 46a, 46b top, to form as opening 62a, 62b among Fig. 6, its split shed 62a is made of as the base as dual-side and copper foil circuit pattern 46a dielectric layer 42a, and opening 62b is made of as the base as dual-side and copper foil circuit pattern 46b dielectric layer 42b.
Then, as shown in Figure 7, carry out a surface coarsening technology on printed circuit board (PCB) 400 surfaces, to increase the roughness on dielectric layer 42a, 42b surface, opening 62a, 62b dual-side and opening 62a, 62b base, and then promoting chemical copper layer that subsequent technique produced adhesion to dielectric layer 42a, 42b surface, opening 62a, 62b dual-side and opening 62a, 62b base, this surface coarsening technology can be a wet etching technics.Then, implement a depositing operation, form one deck chemical copper 72a, 72b and be deposited on dielectric layer 42a, 42b surface, opening 62a, 62b dual-side and opening 62a, 62b bottom.
Then, as shown in Figure 8, photoresist pattern 82a, 82b are transferred to printed circuit board (PCB) 400 two sides, be used as mask (mask), and then carry out electroplating technology, on printed circuit board (PCB) 400 surfaces that do not covered, form copper electroplating layer 92a, 92b as Fig. 9 as circuit by photoresist pattern 82a, 82b, the technology of then removing photoresist is in order to remove photoresist pattern 82a, 82b.
Can use layer protective layer then; photoresist for example; with protection copper electroplating layer 92a, 92b surface; then; carry out etching technics; originally be positioned at chemical copper layer 72a, the 72b because of exposing behind removal photoresist pattern 82a, the 82b under photoresist pattern 82a, the 82b to remove, form structure as Fig. 9.Then form anti-welding flux layer (not shown) on printed circuit board (PCB) 400 surfaces; parcel plating copper layer 92a, 92b form the contact mat (not shown); and form one deck by nickel/gold or organic solderability preservative (Organic SolderPreservative on its surface; OSP) etc. the protective layer (not shown) that material constituted is promptly finished printed circuit board (PCB) of the present invention.
Prior art is owing to must use the mode of estimation, infer copper layer 14a, 14b and dielectric layer 12a, the aligned pattern 18a that 12b covered, 18b and copper foil circuit pattern 16a, the position of 16b, so copper window 32a that leaves and the common and real copper foil circuit pattern of 32b 16a, the position of 16b has bigger error, but, in the present invention because with dielectric layer 42a, copper layer 44a on the 42b, 44b utilizes etching technics to remove earlier, and directly utilize laser beam to find out copper foil circuit pattern 46a, the position of 46b, so copper window position of leaving and prior art are relatively then comparatively more accurate.The present invention is not because need utilize mask (conformal mask) definition copper window, so cost descends, technology shortens, and effectively increase the contraposition ability of laser drill, and promote the ability of live width/line-spacing (line/space), efficiently solve the bottleneck of prior art.
The above only is preferred embodiment of the present invention, and all equalizations of being done according to the present patent application claim change and modify, and all should belong to covering scope of the present invention.