Patent ID: 7501695

Claim:
Large area planar high frequency integrated circuit (HFIC) assembly comprising: a first substrate ( 702 , 703 ) having at least one recess for a chip ( 709 ) having pads and a chip face and at least one planar surface ( 710 , 711 ′) on the side exposing chip pads and the said substrate being conductive at least at this functional side; a second substrate ( 701 ) of conductor-on-insulator having high aspect ratio trenches and conductors ( 705 , 706 , 707 , 708 ) comprising planar surfaces ( 708 , 710 ′), grounding and signal paths for HF- and DC-signals on a functional side arranged to provide connections with chip pads ( 612 ), points of peripheral contacts and area for common ground, when assembled in aligned relation to the said planar surfaces ( 710 , 711 ′, 708 , 710 ′) of each functional side of the first and second substrates, and the said signal paths and grounding each having a conductor facing the functional side of the first substrate, and the said high aspect ratio conductors increasing the air gap ( 616 ) at the chip face; common ground areas ( 710 , 710 ′) between the first and second substrates and these being attached to one substrate and forming shielded cavities ( 615 ) for the signal paths ( 705 , 706 ), and a common ground ( 707 , 708 , 710 , 710 ′, 711 , 711 ′) formed by the first and second substrates encompassing the chip at least adjacent to the HF-signal paths ( 706 ); connections between each pad ( 610 , 612 ) of the chip and the respective signal path ( 603 , 611 ) of the second substrate.