Conductive systems and devices including wires coupled to anisotropic conductive film, and methods of forming the same
Methods and apparatus for eliminating wire sweep and shorting while avoiding the use of under-bump metallization and high cost attendant to the use of conventional redistribution layers. An anisotropically conductive (z-axis) conductive layer in the form of a film or tape is applied to an active surface of a die and used as a base for conductive redistribution bumps formed on the anisotropically conductive layer, bonded to ends of conductive columns thereof and wire bonded to bond pads of the die. Packages so formed may be connected to substrates either with additional wire bonds extending from the conductive redistribution bumps to terminal pads or by flip-chip bonding using conductive bumps formed on the conductive redistribution bumps to connect to the terminal pads. The acts of the methods may be performed at the wafer level. Semiconductor die assemblies may be formed using the methods.
1. A conductive system of a die, comprising:
a conductive terminal of the die;
a wire coupled to the conductive terminal; and
an anisotropic conductive film including a plurality of laterally-spaced conductive paths that are electrically conductive in a single direction, wherein the anisotropic conductive film is adhered on the die and at least two conductive paths of the plurality of laterally-spaced conductive paths are electrically coupled to the wire.
2. The conductive system of claim 1 , further comprising a first bump on the conductive terminal, the first bump being coupled to a first end of the wire.
3. The conductive system of claim 2 , further comprising a second bump on the anisotropic conductive film, the second bump being coupled to a second end of the wire, wherein the at least two conductive paths of the plurality of laterally-spaced conductive paths of the anisotropic conductive film are coupled to the second bump.
4. The conductive system of claim 3 , wherein the anisotropic conductive film is adhered to an active surface of the die.
5. The conductive system of claim 3 , further comprising a third bump coupled to the second end of the wire.
6. The conductive system of claim 5 , further comprising a second wire coupled to the third bump.
7. The conductive system of claim 1 , wherein the anisotropic conductive film is adhered to an active surface of the die.
8. The conductive system of claim 7 , further comprising an electrically insulative layer disposed between the active surface of the die and the anisotropic conductive film to prohibit current from flowing through the anisotropic conductive film to the conductive terminal.
9. A device comprising:
a substrate comprising at least one integrated circuit having a conductive terminal at an active surface of the substrate;
an anisotropic conductive film including a plurality of laterally-spaced conductive paths that are electrically conductive in a single direction, wherein the anisotropic conductive film is adhered on the active surface of the substrate; and
a wire extending between and electrically coupled to the conductive terminal and to a plurality of conductive paths of the plurality of laterally-spaced conductive paths of the anisotropic conductive film.
10. The device of claim 9 , wherein the substrate comprises a semiconductor die.
11. The device of claim 9 , wherein the substrate comprises a semiconductor wafer.