TWI221398B - Circuit board with conductive barrier layers and method for fabricating the same - Google Patents

Abstract

A circuit board with conductive barrier layers and a method for fabricating the same are proposed. A core substrate is formed with a conductive layer on the surface thereof, and an inner circuit layer is formed thereon with the conductive layer. An insulating layer is formed on the inner circuit layer with a plurality of openings to expose the inner circuit layer, and a first barrier layer for preventing metal migration is formed on the surface of the insulating layer and openings. Then, a patterned resist layer is formed on the first barrier layer with a plurality of openings to expose the barrier layer, and a patterned circuit layer is formed within the openings by an electroplating method to electrically connect to the inner circuit layer. After the resist layer and the first barrier layer underneath the resist layer are removed, a second barrier layer is formed on the outer surface of the patterned circuit layer to prevent short and interaction of the circuit layers owing to metal migration.

Description

V. Description of the invention (1) [Technical field to which the invention belongs] The present invention relates to a | two-pronged π method, especially a circuit on a circuit board: ::::: road board and its system to block metal Migration phenomenon, i; Electricity: Two:-Barrier layer, circuit board structure with adhesive force and its insulation layer on the circuit board [Previous technology] /

Lightweight pen products, ρ BE mobile phones, laptops ^ ^ ^ well-known trends, such as (PerSonal d., Video recorders or personal digital assistants from y lgl a assistant), etc .; therefore, these Electronic products and clothing] To use smaller and thinner circuit boards than before; electronic element deduction 侔 2: the trend of miniaturization 'is to combine semiconductor elements and morning cells with various functions on a circuit board to To reduce the demand for circuit boards, so that 'f I circuit board (Clrcuit board) line wiring must have a higher density demand', so for the application of the above-mentioned thinner and high wiring density multilayer circuit boards to electronic products, The process and design of circuit boards will face higher challenges. 0 In circuit board manufacturing, low cost, high reliability, and high wiring density have always been the goals pursued. To achieve this goal, a layer-increasing technology (Bui ld-up), and the folded shoulder reed technology basically refers to the production of a core t ^ ^ (Core c, rcuV; l; r!) i ^ ^ 4 ^ ^ ^ and the conductive layer Conductive blind holes to provide electrical connection between conductive layers Pick up. As shown in FIG. 9, the conventional layered circuit board is formed on a core layer board 300 with a first circuit layer 3 〇 丨, and a through hole is provided in the core layer board 300.

17360 全 恋 .ρΐοΐ Page 6 Friends and Inventions (2) Electricity: Take the circuit layer 301 on the upper and lower surfaces of the two-layer board; then in the ΚΪ t ίϊ, the edge layer 303 'and in the insulation, 3 0 3 shape There is an eye hole 3 0 4 and the eye hole 3 04 can be cleaned. In this way, the insulating layer 3 0 3 can be formed, and the / _ brother / + circuit layer 301 communicates, and the layer circuit 305 can pass through. The blind first-floor road is 3 ° 5, so that the second floor is made into a multi-layer build-up circuit I: Brother-circuit layer 301 is electrically connected but as previously mentioned) ' The circuit board circuit design is becoming more and more dense, and if it is limited by the circuit, the circuit must be increased by adding layers, as = large: the degree is still-a fixed limit 1 between this layer and the layer It is also becoming more and more γ board: the tighter the circuit of the circuit board, or the thinner the layer-to-layer, due to the material =, and =, when the line current is conducted, the conductive copper particles that form the line may migrate and diffuse. And the penetration into the insulating layer 303 caused copper migration in the insulating part between the two phases 〇6, that is, the slowness of cppper migrati〇n = as shown in Figure 10, and even led to the line Circuit short circuit. See, in the circuit board with high wiring density, because the wiring between, or is quite close to 1, the insulation part is relatively small. In the insulating layer 3 0 3 of the insulating part, there are conductive particles and sub-migration particles 306, which reduces the insulation effect. In this way, it is easy to form a short circuit between copper or between layers, making the circuit board non-existent. And wire work; and with the use of 眭 pq w, $ 常 私 ~ 1 increase, the phenomenon of copper migration will become more and more obvious, the copper particles in the insulation part will move 3G6 parts, which will gradually lose the effect of insulation. # 份 ％ Therefore, ik follows the trend of high-density development of circuits, which makes the layers of the layer increase.

1221398 V. Description of the invention (3) Between the layers or between the wires, due to the material limit and the insulation layer is getting thinner and thinner, how to overcome the phenomenon of copper particle migration has become an urgent issue for the development of future electronic products. important topic. [Summary of the Invention] In view of the lack of the aforementioned conventional technology, the main object of the present invention is to provide a circuit board with a conductive barrier layer and a method for manufacturing the same. A metal barrier layer is formed on the surface of the circuit layer. The barrier layer blocks the metal migration phenomenon to avoid short circuits or interference, so that the wiring of the multilayer circuit board can be densely arranged, or the layers can be made thinner and smaller, so as to make more layers of circuit boards. Another object of the present invention is to provide a circuit board with a conductive barrier layer and a method for manufacturing the same. A metal barrier layer is formed on the surface of the circuit layer, so that the circuit layer and the insulation in the circuit board are enhanced by the metal barrier layer. Layer adhesion. To achieve the above object, the present invention provides a circuit board with a conductive barrier layer and a method for manufacturing the same. The preferred implementation steps include: providing a core board having a conductive layer on the surface of the core board, and A base circuit layer is formed on the conductive layer on at least one surface of the laminate; at least one non-conductive insulation layer is added on the base circuit layer, and a plurality of openings are formed on the insulation layer to expose the base circuit layer; A first barrier layer is formed on the insulating layer and the opening surface to prevent metal migration; a patterned barrier layer is formed on the first metal barrier layer, and the barrier layer is formed with a majority of the opening to expose the metal A barrier layer; electroplating in the opening of the barrier layer to form a patterned circuit layer; removing the barrier layer and the first metal barrier layer covered by the barrier layer; and forming a second metal barrier layer on the surface of the patterned circuit layer.该 With the first

17360 Quan 懋 .ptd Page 8 1221398 V. Description of the invention (4) 1. A second metal barrier layer covers the surface of the circuit layer to prevent metal migration, thereby avoiding short circuits or interference, and can enhance patterning. Adhesion between circuit layer and insulation layer. The invention also provides a circuit board with a conductive barrier layer, which mainly includes: a core layer board, a base circuit layer is formed on the surface, and the base circuit layer is electrically connected through a plurality of plated through holes; At least one insulating layer is formed on the base circuit layer of the core board, and a plurality of conductive blind holes electrically connected to the base circuit layer are formed in the insulating layer; at least one patterned circuit layer is Formed on the insulating layer; and a metal barrier layer covering the patterned circuit layer. By covering the circuit layer with a metal barrier layer on the surface of the present invention, the insulation layer between adjacent lines of the circuit layer in the circuit board or the interlayer insulation layer in the circuit board will not have copper migration, so the circuit The arrangement of the insulating layer in the board can be thinner and thinner, so that a thinner and lighter multilayer circuit board can be manufactured. At the same time, in addition to being used to prevent the migration of metal particles, the metal barrier layer can also be used to enhance the adhesion between the circuit layer and the insulating layer, so that the circuit layer is tightly bonded to the insulating layer to avoid detachment. Have a better effect. [Embodiment] In order to make the purpose, characteristics and effects of the present invention more understandable and agreeable, the detailed description with the drawings is as follows. Of course, the present invention may be implemented in various forms. The following description is a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, which will be described before. Please refer to FIGS. 1 to 8 for a conductive barrier layer according to an embodiment of the present invention.

17360 Quan 懋 .ptd Page 9 1221398 V. Schematic cross-sectional view of the process method of the invention description (5). As shown in FIG. 1, a core core board 100 is first provided, and the core board 100 is provided with a first conductive layer 102 and a second conductive layer 103 on each side of an insulating board 101, and The insulating plate 1 〇1 is provided with a plated-through hole ^ 〇1a, so that the first conductive layer 102 and the second conductive layer 103 can be electrically conducted. The material of the conductive layer is mainly metallic copper. As shown in FIG. 2, a patterning process is then performed on the first conductive layer 10 2 of the core board 100 to form a base circuit layer 102 a. As shown in FIG. 3, a non-conductive insulating layer 104 is formed on the surface of the base circuit layer 1028, and the insulating layer is formed with a plurality of first openings 104a to expose part of the base circuit. Layer 1 0 2 a. The first opening 104a is an opening that can be formed as a conductive line or a conductive blind hole. The insulating layer 104 is a thermosetting resin or a photoimageable resin. If the insulating layer 104 is a thermosetting resin, openings 1 0 4a are formed by laser drilling, and the insulating layer 1 If it is a light-developing resin, the opening 1 0 4 a is formed by exposure and development. A first metal barrier layer 105 is formed on the surface of the insulating layer 104 and the opening 104a to prevent metal migration, and the first metal barrier layer 10 is a conductive layer for electroplating, and the first metal barrier layer 10 5 may be one of the group consisting of chromium (Cr), nickel (Ni), origin (Co), princess (Pd), button (Ta), and titanium (Ti), and the metal barrier layer may be Physical vapor deposition, chemical vapor deposition, electroless plating, or chemical deposition, such as sputtering, evaporation, arc vapor deposition, particle beam sputtering

17360 Quan 懋 .ptd Page 10 1221398 V. Description of the invention (6) sputtering), laser ablation deposition (laser ablation deposition), plasma-assisted chemical vapor deposition or electroless plating. At the same time, the resistivities of the metal barrier layer at room temperature are: · Nickel (1 3 // Ω -cm) 'Chromium (6 · 84μ Ω -cm), starting (6.24 // Ω -cm), and (10 8 // Ω -cm) 'group (11.5 / ζ Ω -cm)' titanium (80 // Ω -cm), so these metal barrier layers are all good conductors of electricity, and the coefficient of resistance of copper is 1 6 7 3 // Ω-cm (Reference J 〇h η, Wi i 1 ey & S ο ns, I nc 2000 Μ der η E 1 ec ΐ r ο p 1 atin gp Record) ° In addition, in the previous research, the inventor sputtered a 1 # chromium layer as a conductive layer on an organic material, and then used copper sulfate as a plating solution to form a 2 0 # copper layer by electroplating. Based on this experimental basis, it can be inferred that low-resistance chromium (Cr), nickel (Ni), cobalt (Co), palladium (Pd), tantalum (Ta), and titanium (Ti) can be smoothly plated on the conductive layer. Form a circuit layer made of copper. As shown in FIG. 4, a patterned resist layer 10 is then formed on the first metal barrier layer 105 of the insulating layer 104, and an exposure and a page shadow temple are selected on the resist layer 101 A second opening 1 0 6 a is formed, and at least one second opening ΐ 0 6 a corresponds to the position of the first opening 10 4 a by using the metal barrier layer 1 0 5 of the exposed portion. As shown in Fig. 5 ', the plating process is then performed on the circuit board by electroplating (e 1 ec tr op 1 ati ng) to form a conductive blind hole in the first opening 104a and a second opening in the second opening. A circuit layer 107 is formed in 106a, so that the circuit layer 107 can be electrically connected to the base circuit layer 102a formed on the first conductive layer 1002 through a conductive blind hole, and electroplated and formed. Circuit layer 107 is made of steel

Π360 全懋 .ptd Page 11 1221398 V. Description of the invention (7) Metal, and the electroplating process can be carried out by the second conductive layer on the lower surface of the core board 100, which has not been patterned. 3. Plating The via hole 1 0 1 a, the base circuit layer 102 a on the core board surface, and the metal barrier layer 105 have conductive properties, and can be used as a current conduction path when electroplating, so that the first opening 104 a and A metal layer is formed in the second opening 106 a by electroplating. As shown in FIG. 6, the resist layer 106 is then peeled off, and the metal barrier layer 105 covered by the resist layer 106 is removed by etching, so that the circuit layer 107 is exposed. . Among them, when the part of the metal barrier layer 105 is removed, since the material is different from that of the circuit layer 107, the removal of the metal barrier layer 105 can be avoided to simultaneously destroy the structure of the circuit layer 107 and maintain the original design size. As shown in FIG. 7, after the resist layer 106 is peeled off, the circuit layer 107 is exposed, and a second metal is formed on the surface of the exposed circuit layer 107 through the aforementioned current conduction path and electroplating to form a second metal. The barrier layer 108, or the second metal barrier layer 108 may be directly formed by electroless plating; in this way, the first metal barrier layer 105 and the second metal barrier layer 108 can be used to The circuit layer 1 0 7 is completely covered. Because the outer surface of the circuit layer 10 7 formed by copper metal plating is covered with a first metal barrier layer 105 and a second metal barrier layer 108, the copper-based circuit layer 107 can pass through the first A metal barrier layer 105 and a second metal barrier layer 108 prevent copper migration (Coppermigrati), so that the insulating layer 104 used for insulation will not infiltrate due to the diffusion of copper particles, so That is, the wiring method of the circuit layer 107 can be made tighter, so as not to cause short circuit or interference. Furthermore, the first metal barrier layer 105 and the second metal barrier layer have been formed.

17360 Quan 懋 .ptd Page 12 1221398 V. Description of the Invention (8) Another insulating layer can be formed on the circuit layer 107 of the layer 108 to form a circuit or another circuit with a first metal plate barrier layer. Layer, so that a multilayer circuit board can be fabricated and the second metal resistance can be added as shown in FIG. 8, and then a dry-rejection # 2 0 〇 can be formed on the surface of the multilayer circuit board, and the solder-rejection can be made. The layer 2 0 is formed with a plurality of openings 2 0. The circuit layer 10 7 covered with the second barrier layer 10 8 is exposed outside. The exposed circuit layer 10 7 can be used for electrical connection with external electronic devices. Conductive electrical connection pads, and a metal protective layer, such as a nickel / gold metal layer, may be further formed on the surface of the exposed electrical connection pads for conductive components such as solder balls, wires, or metal bumps. Good electrical conductivity. The metal protective layer i 〇09 can be formed by electroless plating (E 1 ectr 〇 1 ess) to form an exposed surface on the electrical connection pad; or the aforementioned current conduction path can be electroplated to perform electrical connection. : Prepare power ore to form a metal protective layer. The metal protective layer may be one of the group consisting of gold, nickel, palladium, silver, tin, nickel / palladium, chromium / titanium, nickel / gold, palladium / gold, and nickel / palladium / gold. In addition, after the electroplating process is completed, the second conductive layer 100 that has not been patterned on the core layer board 100 can be patterned with an etching technique to obtain a circuit board with a conductive barrier layer. . Of course, the present invention can also perform a build-up process on both sides of the core board at the same time to form a symmetrical structure. In the present invention, because the first metal barrier layer 105 and the second metal barrier layer 108 are formed on the surface of the circuit layer 107, the circuit board circuit layer 107 is adjacent to the circuit. There will be no copper migration between the insulating layer 104 and the interlayer insulating layer of the circuit board. Therefore, the arrangement of the insulating layer in the circuit board can be made lighter and thinner, so that a lighter and thinner multilayer circuit board can be produced.

17360 Quan 懋 .ptd Page 13 1221398 V. Description of the invention (9) In addition to the first metal barrier layer and the second metal barrier layer can be used to prevent the migration of metal particles, according to the industry's know-how, When the barrier layer is chromium, it can also be used to enhance the adhesion between the circuit layer and the insulating layer, so that the circuit layer is tightly bonded to the insulating layer to avoid detachment, so it has a better use effect. However, the specific embodiments described above are only used to illustrate the features and effects of the present invention, rather than to limit the implementable scope of the present invention. Any application without departing from the spirit and technical scope of the present invention is disclosed. Equivalent changes and modifications made by the disclosure of the present invention should still be covered by the scope of patent application described below.

17360 Quan 懋 .ptd Page 14 1221398 Schematic description of the layered resistive guides of the circuit board of the French system I. This is illustrated in Figure 8; Schematic diagram of the electrical circuit of the circuit board of the multi-knowledge system. Picture 5: The image shown is now relocating to the copper circuit of the road. ^ 00 ^ ST-layer multi-knowledge system 100 core board 101 insulation board 101a electroplating Hole 102 First conductive layer 102a Base layer circuit layer 103 Second conductive layer 104 Insulating layer 104a First open V 105 First metal barrier layer 106 Resistive layer 106a Second open π 107 Circuit layer 108 First-Metal barrier layer 109 Metal Protective layer 200 Solder resist layer 201 Opening hole 300 Core board 301 First circuit layer 302 Via hole 303 Insulation layer 304 Blind hole 305 Second circuit layer 306 Copper particles

17360 懋 .ptd Page 15

Claims (1)

1221398 VI. Application for Patent Scope 1. A method for manufacturing a circuit board with a conductive barrier layer includes: providing a core layer board having a conductive layer on the surface of an insulating board, and the insulating board being provided with a plated-through hole, Making the conductive layer on the surface of the core board electrically conductive; forming the conductive layer of the core board into a base circuit layer; forming an insulating layer on the surface of the conductive layer on which the base circuit layer has been formed, and forming a plurality of layers on the insulating layer An opening for conducting with the base circuit layer; forming a first metal barrier layer on the insulating layer and the surface of the opening; forming a patterned resist layer on the first metal barrier layer, and the resist layer having most exposed portions outside the opening A first metal barrier layer; forming a patterned circuit layer in the opening of the resist layer by electroplating, and electrically conducting the patterned circuit layer and the base circuit layer; removing the resist layer and the first metal it covers A barrier layer; and forming a second metal barrier layer on the surface of the exposed patterned circuit layer, and covering the patterned circuit layer with the first and second metal barrier layers. 2. If the method of manufacturing a circuit board with a conductive barrier layer according to item 1 of the scope of the patent application includes forming another insulating layer on the patterned circuit layer on which the first and second metal barrier layers have been formed, Then, according to the above steps, another patterned circuit layer having first and second metal barrier layers is formed to form a multilayer circuit board. 3. If the method of manufacturing a circuit board with a conductive barrier layer in the scope of patent application item 1 or 2 includes forming a solder resist layer on the surface of the multilayer circuit board, and 17360 Quan 懋 .ptd Page 16 1221398 6. The scope of the patent application makes the solder resist layer formed with a large number of openings and exposes the circuit layer covered thereunder as an electrical connection pad part, and the surface of the exposed electrical connection pad A metal protective layer may be further formed. 4. For the method for manufacturing a circuit board with a conductive barrier layer as described in the scope of patent application No. 3, wherein the metal protective layer may be gold, nickel, silver, silver, tin, nickel / Ig, chromium / titanium, nickel / gold , Iε / gold and nickel / barrel / gold. 5. For the method of manufacturing a circuit board with a conductive barrier layer according to item 1 or 2 of the scope of patent application, wherein the conductive layer on one side of the core board can be patterned to form a base circuit layer, and the core layer is used. The conductive layer that has not been patterned on the other side of the board and the plated through holes formed in the core board can be used as a current conduction path when plating is performed to form a build-up circuit on a single side of the core board. 6. For the method of manufacturing a circuit board with a conductive barrier layer according to item 1 or 2 of the scope of patent application, wherein the conductive layer on the surface of the core board can be patterned at the same time to form a base circuit layer, which is placed on two sides of the core board At the same time, a build-up circuit is formed. 7. For the method of manufacturing a circuit board with a conductive barrier layer according to item 1 or 2 of the patent application scope, wherein the insulating layer is a thermosetting resin, and the opening of the insulating layer is formed by laser drilling. 8. The method of manufacturing a circuit board with a conductive barrier layer according to item 1 of the patent application scope, wherein the insulating layer is a light developing resin, and the opening of the insulating layer is formed by an exposure and development process. 9. Circuit board system with conductive barrier layer such as the scope of patent application 17360 Quan 懋 .ptd Page 17 1221398 6. Application for Patent Scope Method, where the patterned circuit layer is copper metal. 10. The method for manufacturing a circuit board with a conductive barrier layer according to item 1 of the scope of patent application, wherein the first and second metal barrier layers are chromium (Cr), nickel (Ni), and inscription (Co) One of the groups consisting of, Ji (Pd), group (Ta), and titanium (Ti). 1 1. A circuit board with a conductive barrier layer, comprising: a core layer board having a base layer circuit layer formed on its surface and having plated through holes for electrically connecting the base layer circuit layer; at least one insulating layer, It is formed on the base circuit layer of the core board, and a plurality of conductive blind holes are formed in the insulation layer to be electrically connected with the base circuit layer. At least one patterned circuit layer is formed on the insulation layer. And a metal barrier layer covering the patterned circuit layer. 1 2. For a circuit board with a conductive barrier layer as described in item 11 of the scope of the patent application, it further includes a solder resist layer formed with a large number of openings and exposed circuit layers covering the solder resist layer. An electrical connection pad portion; and a metal protective layer formed on the surface of the exposed electrical connection pad. 013. For example, a circuit board with a conductive barrier layer as described in item 12 of the patent application scope, wherein the metal The protective layer may be one of the group consisting of gold, copper, silver, silver, tin, copper / Ibar, chromium / titanium, nickel / gold, Ιε / gold, and nickel / Ιε / gold. 17360 Quan 懋 .ptd Page 18 1221398 6. Scope of Patent Application 1 4. For the circuit board with conductive barrier layer as described in item 11 of the patent application scope, the insulation layer is a thermosetting resin. 15. The circuit board with a conductive barrier layer according to item 11 of the scope of patent application, wherein the insulating layer is a light developing resin. 16. The circuit board with a conductive barrier layer according to item 11 of the scope of patent application, wherein the patterned circuit layer is copper metal. 1 7. The circuit board with a conductive barrier layer according to item 11 of the scope of patent application, wherein the metal barrier layer is chromium (C r), nickel (N i), palladium (C 〇), palladium (Pd), tantalum (Ta), or titanium (Ti). 17360 懋 .ptd Page 19