Composite film for use in led wafer-level packaging process

A composite film for use in an LED wafer-level packaging process to facilitate adhesion of an LED wafer to a carrier, dicing, and a heating packaging process carried out at 150˜180° C., so as to complete the LED wafer-level packaging process and then cut the LED wafer into single die package, the composite film comprising:

• a substrate comprising a first surface and a second surface;
• a heat-resisting pressure-sensing adhesive being of a thickness less than 30 μm, formed on the first surface of the substrate, and adapted to allow the LED wafer to be adhered to the substrate, wherein the heat-resisting pressure-sensing adhesive has an adhesiveness strength greater than 250 gf/inch before heating and an adhesiveness strength greater than 400 gf/inch after heating;
• and
• a heat-resisting thermally-visbreaking pressure-sensing adhesive formed on the second surface of the substrate and adapted to allow the substrate to be adhered to the carrier, wherein the heat-resisting thermally-visbreaking pressure-sensing adhesive has an adhesiveness strength greater than 200 gf/inch before heating to prevent die dislocation during the packaging process and an adhesiveness strength less than 150 gf/inch after heating, thereby allowing the carrier to be detached from the composite film easily upon completion of the LED wafer-level packaging process.