PACKAGING-BEFORE-ETCHING FLIP CHIP 3D SYSTEM-LEVEL METAL CIRCUIT BOARD STRUCTURE AND TECHNIQUE THEREOF

摘要

Provided are a packaging-before-etching flip chip 3D system-level metal circuit board structure and technique thereof. The metal circuit board structure comprises a metal substrate frame; the front face of the metal substrate frame is provided with pins; the front faces of the pins are provided with conductive posts; chips are installed in a flip manner between the pins via underfills; the peripheral areas of the pins, the conductive posts and the chip are encapsulated with molding compound, the top of the molding compound being parallel to the tops of the conductive posts; and the surfaces of the metal substrate frame, the pins and the conductive posts exposing out of the molding compounds are provided with an anti-oxidation layer, thus solving the problem of limited functionality and application of a traditional metal lead frame due to the fact that objects cannot be embedded therein.

主权项

1. A method for manufacturing a packaging-before-etching flip chip 3D system-in-package metal circuit board structure, comprising:
step 1: providing a metal substrate; step 2: pre-plating a surface of the metal substrate with a copper material, wherein the surface of the metal substrate is pre-plated with a layer of copper material; step 3: attaching a photoresist film, wherein a front surface and a back surface of the metal substrate which have been pre-plated with the copper material in step 2 are respectively attached with the photoresist film which can be exposed and developed; step 4: removing a part of the photoresist film on the front surface of the metal substrate, wherein the front surface of the metal substrate, which has been attached with the photoresist film in step 3 is exposed and developed with a pattern using an exposure and development equipment, and the part of the photoresist film in the pattern is removed, so as to expose a region of the front surface of the metal substrate to be plated with a metal wiring layer later; step 5: plating with the metal wiring layer, wherein the region of the front surface of the metal substrate from which the part of the photoresist film has been removed in step 4 is plated with the metal wiring layer, so that a die pad and a lead are formed on the front surface of the metal substrate; step 6: attaching a photoresist film, wherein the front surface of the metal substrate which has been plated with the metal wiring layer in step 5 is attached with the photoresist film which can be exposed and developed; step 7: removing a part of the photoresist film on the front surface of the metal substrate, wherein the front surface of the metal substrate which has been attached with the photoresist film in step 6 is exposed and developed with a pattern using an exposure and development equipment, and the part of the photoresist film in a pattern is removed, so as to expose a region of the front surface of the metal substrate to be plated with a conductive pillar later; step 8: plating with the conductive pillar, wherein the region of the front surface of the metal substrate from which the part of the photoresist film has been removed in step 7 is plated with the conductive pillar; step 9: removing the photoresist film, wherein the photoresist film on the surface of the metal substrate is removed; step 10: bonding die, wherein a chip is flipped on a front surface of the die pad and the lead formed in step 5 by underfills; step 11: molding with an epoxy resin, wherein the molding with the epoxy resin for protecting is performed on the front surface of the metal substrate after the bonding die has been performed; step 12: grinding a surface of the epoxy resin, wherein the surface of the epoxy resin is ground after the molding with the epoxy resin has been performed in step 12; step 13: attaching a photoresist film, wherein the front surface and the back surface of the metal substrate are attached with the photoresist film which can be exposed and developed after the surface of the epoxy resin has been ground in step 12; step 14: removing a part of the photoresist film on the back surface of the metal substrate, wherein the back surface of the metal substrate, which has been attached with the photoresist film in step 13, is exposed and developed with a pattern using an exposure and development equipment, and the part of the photoresist film in the pattern is removed, so as to expose a region of the back surface of the metal substrate to be etched later; step 15: etching, wherein chemical etching is performed in the region of the back surface of the metal substrate from which the part of the photoresist film has been removed in step 14; step 16: removing the photoresist film, wherein the photoresist film on the surface of the metal substrate is removed, the photoresist film is removed by softening with chemicals and cleaning with high pressure water; and step 17: plating with an anti-oxidizing metal layer or coating with an organic solderability preservative, wherein an exposed metal surface of the metal substrate surface from which the photoresist film has been removed in step 17 is plated with the anti-oxidizing metal layer or is coated with the organic solderability preservative.