Semiconductor device with enclosed cavity and method therefor

A method of manufacturing a semiconductor device, the method comprising:

• placing a semiconductor die on a carrier substrate;
• placing a radio frequency (RF) sub-assembly on the carrier substrate, the RF sub-assembly comprising:
• a sacrificial blank;
• a patterned dielectric material formed on a first side of the sacrificial blank;
• a conductive radiant element formed on the first side of the sacrificial blank, the conductive radiant element formed in a same horizontal plane as the patterned dielectric material;
• and
• a conductive shield formed at least on outer sidewalls of the sacrificial blank;
• encapsulating with an encapsulant at least a portion of the semiconductor die and the RF sub-assembly;
• separating the carrier substrate from a first major side of the encapsulated semiconductor die and RF sub-assembly to expose a second side of the sacrificial blank;
• etching the sacrificial blank to form a cavity in the RF sub-assembly, the conductive radiant element and the conductive shield exposed through the cavity;
• and
• affixing a package lid on the first major side of the encapsulated semiconductor die and RF sub-assembly, the package lid configured to serve as a signal reflector for propagation of an RF signal.

A method of manufacturing a semiconductor device, the method comprising:

• placing a semiconductor die on a carrier substrate;
• placing a radio frequency (RF) sub-assembly on the carrier substrate, the RF sub-assembly comprising:
• a sacrificial blank;
• a patterned dielectric material formed on a first side of the sacrificial blank;
• a conductive radiant element formed on the first side of the sacrificial blank;
• and
• a conductive shield formed at least on outer sidewalls of the sacrificial blank, the patterned dielectric material configured to electrically isolate the conductive radiant element from the conductive shield;
• encapsulating with an encapsulant at least a portion of the semiconductor die and the RF sub-assembly;
• separating the carrier substrate from a first major side of the encapsulated semiconductor die and RF sub-assembly to expose a second side of the sacrificial blank;
• etching the sacrificial blank to form a cavity in the RF sub-assembly, the conductive radiant element and the conductive shield exposed through the cavity;
• and
• affixing a package lid on the first major side of the encapsulated semiconductor die and RF sub-assembly, the package lid enclosing the cavity.