A substrate that includes a core layer comprising a first surface and a second surface, a plurality of core interconnects located in the core layer, a high-density interconnect portion located in the core layer, a first dielectric layer coupled to the first surface of the core layer, a first plurality of interconnects located in the first dielectric layer, a second dielectric layer coupled to the second surface of the core layer, and a second plurality of interconnects located in the second dielectric layer. The high-density interconnect portion includes a first redistribution dielectric layer and a first plurality of high-density interconnects located in the first redistribution dielectric layer. The high-density interconnect portion may provide high-density interconnects.

Disclosed are semiconductor packages and their fabricating methods. The method includes preparing a semiconductor chip with a pillar pattern on a bottom surface thereof, placing the semiconductor chip side by side with a connection substrate with a conductive pad on a bottom surface thereof, forming a molding layer on the bottom surfaces of the connection substrate and the semiconductor chip to cover the pillar pattern and the conductive pad, forming a first redistribution substrate on top surfaces of the connection substrate, the semiconductor chip, and the molding layer and directly in physical contact with the top surface of the semiconductor chip, and performing a grinding process on a bottom surface of the molding layer to expose the pillar pattern and the conductive pad. An outer sidewall of the connection substrate is vertically aligned with that of the first redistribution substrate.

A substrate that includes a core layer comprising a first surface and a second surface, a plurality of core interconnects located in the core layer, a high-density interconnect portion located in the core layer, a first dielectric layer coupled to the first surface of the core layer, a first plurality of interconnects located in the first dielectric layer, a second dielectric layer coupled to the second surface of the core layer, and a second plurality of interconnects located in the second dielectric layer. The high-density interconnect portion includes a first redistribution dielectric layer and a first plurality of high-density interconnects located in the first redistribution dielectric layer. The high-density interconnect portion may provide high-density interconnects.

A method of forming a semiconductor device is provided. The method includes placing a semiconductor die on a carrier substrate and placing a sacrificial blank on the carrier substrate with a routing structure attached to the sacrificial blank. At least a portion of the semiconductor die, sacrificial blank, and routing structure are encapsulated with an encapsulant. The carrier substrate is separated from a first side of the encapsulated semiconductor die, sacrificial blank, and routing structure to expose a surface of the sacrificial blank. The sacrificial blank is etched to form a cavity in the encapsulant and expose a portion of the routing structure exposed through the cavity.

A system-level packaging method includes providing a packaging substrate having a first functional surface and a second surface with wiring arrangement within the packaging substrate and between the first functional surface and the second surface. The method also includes forming at least two package layers on the first functional surface of the packaging substrate, wherein each package layer is formed by subsequently forming a mounting layer, a sealant layer, and a wiring layer. Further, the method includes forming a top sealant layer and planting connection balls on the second functional surface of the packaging substrate.

A system-level packaging method includes providing a packaging substrate having a first functional surface and a second surface with wiring arrangement within the packaging substrate and between the first functional surface and the second surface. The method also includes forming at least two package layers on the first functional surface of the packaging substrate, wherein each package layer is formed by subsequently forming a mounting layer, a sealant layer, and a wiring layer. Further, the method includes forming a top sealant layer and planting connection balls on the second functional surface of the packaging substrate.

A chip-on-film (COF) package includes a semiconductor chip comprising a plurality of external connection pads for connecting to outside of the semiconductor chip; a conductive portion electrically connected to the plurality of external connection pads; a base film attached to a lower end of the conductive portion and having an upper surface and a lower surface opposite each other; and a protective layer covering the conductive portion on the upper surface of the base film. The protective layer covers sidewalls and a lower surface of the semiconductor chip, and the conductive portion comprises a plurality of conductive lines disposed on the upper surface of the base film, and a plurality of via structures formed integrally with the plurality of conductive lines and electrically connected to the plurality of external connection pads.