Polyimide composition for package structure, package structure and method of fabricating the same

A package structure, comprising:

• a semiconductor die;
• an insulating encapsulant encapsulating the semiconductor die;
• a redistribution layer disposed on the semiconductor die and the insulating encapsulant, wherein the redistribution layer comprises a plurality of dielectric layers and a plurality of conductive layers stacked alternately, and at least one of the plurality of dielectric layers is formed by curing a polyimide composition, wherein the polyimide composition comprises:
• a polyimide precursor;
• a cross-linker;
• a photosensitizer;
• a first additive, wherein the first additive comprises a polyether based compound;
• a second additive, wherein the second additive comprises a siloxane based compound;
• and
• a solvent;
• wherein the polyimide composition has more than 98% cyclization of the polyimide precursor when the polyimide composition is cured at a temperature range of 160° C. to 200° C.

A method of fabricating a package structure, comprising:

• bonding at least one semiconductor die on a carrier;
• forming an insulating encapsulant encapsulating the at least one semiconductor die;
• forming a redistribution layer on the insulating encapsulant and on the at least one semiconductor die, wherein the forming of the redistribution layer comprises:
• forming a plurality of dielectric layers and a plurality of conductive layers stacked alternately, and at least one of the plurality of dielectric layers is formed by providing a polyimide composition and curing the polyimide composition at a temperature range of 160° C. to 200° C., wherein the polyimide composition comprises:
• a polyimide precursor;
• a cross-linker;
• a photosensitizer;
• a first additive, wherein the first additive comprises a polyether based compound;
• a second additive, wherein the second additive comprises a siloxane based compound;
• and
• a solvent;
• wherein the polyimide composition has more than 98% cyclization of the polyimide precursor when the polyimide composition is cured.