Magnetic hold-down for foil substrate processing
View Patent ↗A method for forming an electronic circuit disposes a plurality of magnets onto a flux plate to form a magnetic platen. A substrate package is formed using the magnetic platen and, stacked against the magnetic platen, a non-magnetic carrier and a substrate layer, with a bonding material sandwiched between the carrier and the substrate layer, and with the carrier layer disposed nearest the magnetic platen. A fused wafer stack is formed by heating the substrate package to adhere the substrate layer to the carrier. The fused wafer stack is removed from the magnetic platen and the circuit fabricated on the substrate layer.
1. A method for forming an electronic circuit comprising:
disposing a plurality of magnets onto a flux plate to form a magnetic platen;
forming a substrate package comprising the magnetic platen and, stacked against the magnetic platen, a non-magnetic carrier and a substrate layer or the non-magnetic carrier, the substrate layer and a clamping layer of a magnetic material, with a bonding material sandwiched between the carrier and the substrate layer, and with the carrier layer disposed nearest the magnetic platen;
forming a fused wafer stack by heating the substrate package to adhere the substrate layer to the carrier, wherein the magnetic platen provides a magnetic attraction between the substrate layer or the clamping layer and the magnetic platen while the fused wafer stack is formed;
removing the fused wafer stack from the magnetic platen; and
fabricating the circuit on the substrate layer.
2. The method of claim 1 wherein the substrate layer is a magnetic material.
3. The method of claim 1 wherein the substrate layer is a metal foil.
4. The method of claim 1 wherein forming the substrate package further comprises disposing a clamping foil of a magnetic material as the clamping layer against the substrate layer.
5. The method of claim 4 wherein the substrate layer is plastic.
6. The method of claim 1 wherein the non-magnetic carrier is glass.
7. The method of claim 1 further comprising delaminating the substrate layer from the carrier.
8. The method of claim 1 wherein forming the substrate package further comprises sliding the carrier along the magnetic platen while directing a flow of compressed air through one or more ports provided in the flux plate.
9. The method of claim 8 wherein directing the flow of compressed air further comprises providing an air nozzle having a magnetic coupling to the flux plate.
10. The method of claim 1 wherein removing the fused wafer stack from the magnetic platen comprises directing compressed air between the fused wafer stack and the magnetic platen.
11. The method of claim 1 wherein the bonding material is in sheet form.
12. A method for forming an electronic circuit comprising:
forming a magnetic platen by magnetizing a magnetic material;
forming a substrate package comprising the magnetic platen and, stacked against the magnetic platen, a non-magnetic carrier and a substrate layer or the non-magnetic carrier, the substrate layer and a clamping layer of a magnetic material, with a bonding material sandwiched between the carrier and the substrate layer, and with the carrier layer disposed nearest the magnetic platen;
forming a fused wafer stack by heating the substrate package to adhere the substrate layer to the carrier, wherein the magnetic platen provides a magnetic attraction between the substrate layer or the clamping layer and the magnetic platen while the fused wafer stack is formed;
removing the fused wafer stack from the magnetic platen; and
fabricating the circuit on the substrate layer.