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 μm to 40 μm 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 μm, 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.
Priority Claims (2)
Number |
Date |
Country |
Kind |
11-36365 |
Feb 1999 |
JP |
|
11-89782 |
Mar 1999 |
JP |
|
Parent Case Info
This is a divisional of Ser. No. 09/498,482, filed Feb. 4, 2000.
US Referenced Citations (19)
Foreign Referenced Citations (2)
Number |
Date |
Country |
10-294400 |
Nov 1998 |
JP |
2000-183535 |
Jun 2000 |
JP |