Printed wiring board for semiconductor plastic package

• US 6,479,760 B2
• Filed: 10/11/2001
• Issued: 11/12/2002
• Est. Priority Date: 02/15/1999
• Status: Expired due to Term

• Current Assignee: Mitsubishi Gas Chemical Company Incorporated (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Gas Chemical Company Incorporated (Mitsubishi Electric Corporation)
• Inventors: Ikeguchi, Nobuyuki, Kimbara, Hidenori, Komatsu, Katsuji
• Primary Examiner(s): Talbott, David L.
• Assistant Examiner(s): PATEL, ISHWARBHAI B
• Application Number:
  US09/973,688
• Publication Number:
  US 20020039644A1
• Time in Patent Office: 397 Days
• Field of Search: 174/260, 174/255, 174/264, 174/266, 174/258, 174/259, 174/262, 174/263, 174/267, 174/254, 174/256, 361/760, 361/748, 361/749, 361/750, 361/773, 361/783, 361/792, 361/793, 361/808, 361/743, 361/746, 361/767, 361/768, 361/772, 257/737, 257/738, 257/778, 257/784, 257/774, 257/698, 257/702, 257/709
• US Class Current: 174/260
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/05647 Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2224/131 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/43 Manufacturing methods
• CPC Class Codes: H01L 2224/45 of an individual wire connector
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48228 the bond pad being disposed in a recess of the surface of the item
• CPC Class Codes: H01L 2224/73204 the bump connector being embedded into the layer connector
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 23/13 characterised by the shape
• CPC Class Codes: H01L 23/49811 Additional leads joined to the metallisation on the insulating substrate, e.g. pins, bumps, wires, flat leads H01L23/49827 takes precedence
• CPC Class Codes: H01L 23/49816 Spherical bumps on the substrate for external connection, e.g. ball grid arrays [BGA]
• CPC Class Codes: H01L 23/49866 characterised by the materials materials of the substrates H01L23/14, of the lead-frames H01L23/49579
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 24/73 Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/0002 : Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01012 : Magnesium [Mg]
• CPC Class Codes: H01L 2924/01014 : Silicon [Si]
• CPC Class Codes: H01L 2924/01015 : Phosphorus [P]
• CPC Class Codes: H01L 2924/01019 : Potassium [K]
• CPC Class Codes: H01L 2924/01023 : Vanadium [V]
• CPC Class Codes: H01L 2924/01028 : Nickel [Ni]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/0103 : Zinc [Zn]
• CPC Class Codes: H01L 2924/01042 : Molybdenum [Mo]
• CPC Class Codes: H01L 2924/01045 : Rhodium [Rh]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/01051 : Antimony [Sb]
• CPC Class Codes: H01L 2924/01056 : Barium [Ba]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/01078 : Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/01083 : Bismuth [Bi]
• CPC Class Codes: H01L 2924/01105 : Rare earth metals
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/04941 : TiN
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/15311 : being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/40252 : CO2 LASER
• CPC Class Codes: H05K 1/0373 : containing additives, e.g. fillers H05K1/036 takes precedence
• CPC Class Codes: H05K 1/112 : directly combined with via connections
• CPC Class Codes: H05K 2201/0209 : Inorganic, non-metallic particles
• CPC Class Codes: H05K 2201/09472 : Recessed pad for surface mounting recess in pad H05K2201/09745; Recessed electrode of component
• CPC Class Codes: H05K 2201/09509 : Blind vias, i.e. vias having one side closed
• CPC Class Codes: H05K 2201/0979 : Redundant conductors or connections, i.e. more than one current path between two points
• CPC Class Codes: H05K 3/0038 : combined with laser drilling through a metal layer
• CPC Class Codes: H05K 3/3436 : having an array of bottom contacts, e.g. pad grid array or ball grid array components
• CPC Class Codes: H05K 3/4629 : laminating inorganic sheets comprising printed circuits, e.g. green ceramic sheets
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 428/24917 : including metal layer
• CPC Class Codes: Y10T 428/31681 : Next to polyester, polyamide or polyimide [e.g., alkyd, glue, or nylon, etc.]

Abstract

Provided is a printed wiring board for a chip size scale package, which overcomes the poor adhesion of solder balls to a base material which poor adhesion is caused by a recent decrease in the size of the solder balls, and in the chip size scale package, the distortion of the printed wiring board is decreased and the distortion of a semiconductor package formed by mounting a semiconductor chip on the printed wiring board by wire bonding or flip chip bonding is decreased. The printed wiring board has, as a substrate for a chip scale package, a double-side copper-clad laminate formed of an insulation layer and having copper foils on both surfaces, wherein the double-side copper-clad laminate has an upper copper foil surface and a lower copper foil surface, the upper copper foil surface has a wire bonding or flip chip bonding terminal and has a copper pad in a position where the copper pad can be electrically connected to said wire bonding or flip chip bonding terminal and can be connected to a blind via hole formed in the lower copper surface, the lower copper foil surface has a solder-balls fixing pad in a position corresponding to said copper pad, the solder-balls-fixing pad has at least 2 blind via holes within itself, and the solder-balls-fixing pad connected to a reverse surface of the copper pad with a conductive material is electrically connected with solder balls which are melted and filled in blind via holes so as to be mounded.

Claims

1. A printed wiring board for a semiconductor package, which printed wiring board is formed by providing a copper-clad laminate formed of copper foils and a base material of a 150 μ

m to 40 μ

m thick glass fabric impregnated with a thermosetting resin composition, one copper foil on one surface of the substrate and one copper foil on the other surface of the substrate, forming a semiconductor chip bonding terminal and a circuit for connecting said bonding terminal in the front surface of the copper-clad laminate, forming a solder ball connecting pad and a circuit for connecting said pad in the reverse surface of the copper-clad laminate, forming a through hole conductive material connecting the circuit in the front surface to the circuit in the reverse surface to form a circuit board, then, stacking prepreg sheets of glass fabric base material/thermosetting resin on the entire front and reverse surfaces, laminating the resultant set under pressure and under heat, and then removing base material formed of the glass fabric and the thermosetting resin composition on at least part of the surface of the bonding terminal and on at least part of the surface of the solder balls connecting pad, to expose a circuit.

2. A printed wiring board according to claim 1, which is a very thin BGA type semiconductor package.

3. The printed wiring board according to claim 1, wherein the glass fabric is at least one woven fabric having a thickness of 50±

10 μ

m, a weight of 35 to 60 g/m² and a gas permeability of 5 to 25 cm³/cm².sec.

4. The printed wiring board according to claim 1, wherein the base material formed of the glass fabric and the thermosetting resin composition on at least part of the surface of the bonding terminal and on at least of the surface of the solder balls connecting pad is removed by a sand blast method, to expose a circuit.

5. The printed wiring board according to claim 1, wherein the thermosetting resin composition is a thermosetting resin composition containing, as an essential component, a polyfunctional cyanate ester and a prepolymer of said cyanate ester.

6. The printed wiring board according to claim 1, wherein the resin composition of the copper-clad laminate contains 10 to 80% by weight of an insulating inorganic filler.

7. The printed wiring board according to claim 6, wherein the insulating inorganic filler is aluminum hydroxide or magnesium hydroxide.