Package structure and fabricating method thereof

A package structure, comprising:

• a redistribution circuit structure comprising a first surface and a second surface opposite to the first surface;
• a wiring substrate disposed on the first surface of the redistribution circuit structure;
• an insulating encapsulation disposed on the first surface of the redistribution circuit structure and laterally encapsulating the wiring substrate;
• a semiconductor device disposed on the second surface of the redistribution circuit structure, wherein the semiconductor device is electrically connected to the wiring substrate through the redistribution circuit structure;
• and
• a stiffener ring adhered with the second surface of the redistribution circuit structure by an adhesive, wherein the stiffener ring is adhered with an outermost dielectric layer of the redistribution circuit structure by the adhesive, and a thickness of the outermost dielectric layer of the redistribution circuit structure is greater than 7 micrometers.

A method, comprising:

• mounting a wiring substrate over a first surface of a redistribution circuit structure;
• laterally encapsulating the wiring substrate with an insulating encapsulation;
• forming a buffer layer over a second surface of the redistribution circuit structure;
• mounting a semiconductor device over buffer layer, and the semiconductor device being electrically connected to the wiring substrate through the redistribution circuit structure;
• and
• adhering a stiffener ring with the buffer layer by an adhesive.