Method of manufacturing printed circuit board and multi-layered PCB

• US 6,902,660 B2
• Filed: 08/30/2002
• Issued: 06/07/2005
• Est. Priority Date: 08/21/2002
• Status: Expired due to Fees

• Current Assignee: Korea Advanced Institute of Science and Technology
• Original Assignee: Korea Advanced Institute of Science and Technology
• Inventors: Yu, Jin, Lee, Hyuek Jae
• Primary Examiner(s): Wong, Edna
• Application Number:
  US10/231,052
• Publication Number:
  US 20040035711A1
• Time in Patent Office: 1,012 Days
• Field of Search: 205/67, 205/78, 205/125
• US Class Current: 205/125
• CPC Class Codes: C25D 5/02 Electroplating of selected surface areas
• CPC Class Codes: H05K 2201/0154 Polyimide
• CPC Class Codes: H05K 2203/0733 Method for plating stud vias, i.e. massive vias formed by plating the bottom of a hole without plating on the walls
• CPC Class Codes: H05K 3/205 using a pattern electroplated or electroformed on a metallic carrier
• CPC Class Codes: H05K 3/384 by plating
• CPC Class Codes: H05K 3/423 characterised by electroplating method
• CPC Class Codes: H05K 3/4617 characterized by laminating only or mainly similar single-sided circuit boards

Abstract

Disclosed is a fabrication method of a printed circuit board, consisting of plating a metal on a pattern-formed metallic substrate to form a conductive metal line; forming a polymer layer as a base substrate over the conductive metal line-formed metallic substrate and drying the formed polymer layer; forming a via hole in the polymer layer, followed by plugging the formed via hole by electroplating; and removing the metallic substrate. The method is advantageous in terms of maximum efficiency of use of the surface area of PCB, and fineness and high integration of circuits because of not requiring an additional etching process.

Claims

1. A method of manufacturing a printed circuit board, comprising the following steps of:

(a) plating a metal between patterns on a pattern-formed metallic substrate, to form a conductive metal line;

(b) forming a polymer layer as a base substrate over the patterns and the conductive metal line formed between the patterns on the pattern-formed metallic substrate and drying the formed polymer layer, the conductive metal line being relatively weakly bonded to the metallic substrate compared to the polymer layer to permit separation of the conductive metal line from the metallic substrate without;

(c) forming a via hole in the polymer layer, followed by plugging the formed via hole by means of electroplating; and

(d) removing the metallic substrate without etching.

2. The method as set forth in claim 1, wherein the step (a) further comprises coating a coupling agent onto the patterns and the conductive metal line formed on the metallic substrate between the patterns.

3. The method as set forth in claim 1, wherein the step (a) further comprises forming a chromium layer on the conductive metal line.

4. The method as set forth in claim 1, wherein the metallic substrate is made of a material selected from the group consisting of stainless steel, aluminum and nickel.

5. The method as set forth in claim 1, wherein the conductive metal line is made of a material selected from the group consisting of copper, aluminum, chromium, tin, nickel, gold and alloys thereof.

6. The method as set forth in claim 1, wherein the polymer layer is made of a polymer selected from the group consisting of polyimides, polyimide resins and prepregs.

7. The method as set forth in claim 1, wherein the patterns on the pattern-formed metallic substrate are photoresist which has been dried at a drying temperature upon formation of the patterns on the metallic substrate, and wherein, in the step (b), the polymer layer is dried at a temperature lower than said drying temperature of said photoresist.

8. The method as set forth in claim 7, wherein the polymer layer is dried at 80-110°

C.

9. The method as set forth in claim 1, wherein the via hole is formed by any one selected from the group consisting of YAG, CO₂ and UV lasers.

10. The method as set forth in claim 1, wherein the via hole is plugged with a metal selected from the group consisting of solder, tin, nickel, copper, chromium, aluminum, gold and alloys thereof.