Ceramic antenna module and methods of manufacture thereof
Antenna modules that contain composite meta-material dielectric bodies that have high effective values of real permittivity and reductions in physical lengths of electrically conducting elements.
1. An antenna module, comprising:
a composite dielectric body including at least one ceramic dielectric inclusion composed of at least one material selected from the group consisting of materials having a relative dielectric permittivity ≥10 and materials having a relative dielectric permeability ≠1, the at least one ceramic dielectric inclusion embedded in a dielectric host material selected from the group consisting of amorphous silica, titania, tantalates, pure alumina, admixtures thereof, and an organic media such that the composite dielectric body has an effective permittivity ≥4;
a metallization layer adjacent the composite dielectric body and including a ground plane and at least one contact pad; and
at least one electrically conductive element disposed parallel to the metallization layer and electrically connected with the at least one contact pad, each conductive element disposed relative to the composite dielectric body such that the conductive element is resonant over a band of frequencies and has a length that is ≤50% of the length that would be required to maintain the same resonance without the composite dielectric body,
wherein the composite dielectric body further comprises a base dielectric layer of high-k ceramic material having a relative permittivity ε R ≥10 disposed adjacent the ground plane, the base dielectric layer having a corresponding one or more vias to accommodate the electrical connection between the at least one electrically conductive element and the at least one contact pad, the base dielectric layer is uniformly dimensioned so as to modify the input impedance of the at least one electrically conductive element to substantially match an output impedance of at least one semiconductor die when electrically connected to the at least one contact pad.
2. The module of claim 1 , further comprising:
an interconnect structure providing the electrical connection between the at least
one contact pad and the at least one semiconductor die, the interconnect structure including an oxide ceramic body, at least two conductive contacts, and at least one transmission line embedded in the oxide ceramic body at a uniform distance above the ground plane and providing an electrical pathway between the at least two conductive contacts through the oxide ceramic body; and
wherein the input impedance of the at least one electrically conductive element substantially matches an output impedance of the at least one transmission line.
3. The module of claim 1 , wherein the relative permittivity ε R of the high-k ceramic layer is ≥60.
4. The module of claim 1 , wherein the high-k ceramic layer is composed of at least one high permittivity ceramic selected from the group consisting of titania, tantalum pentoxide, and niobates.
5. The module of claim 1 , wherein the at least one electrically conductive element has an intrinsic impedance that is less than or equal to 50Ω.
6. The module of claim 1 , wherein:
the at least one electrically conductive element is composed of discrete wire; and
the thickness of the high-k ceramic material layer is less than about 25 microns.
7. The module of claim 1 , wherein the high-k ceramic base dielectric layer has a relative permittivity ε R greater than or equal to 100 and a thickness that is between about 0.25 to about 25 microns.
8. The module of claim 1 , wherein the high-k ceramic material layer has a relative permittivity ε R greater than or equal to 400 and a thickness that is between about 0.25 to about 5 microns.
9. An antenna module, comprising:
a composite dielectric body including at least one ceramic dielectric inclusion
composed of at least one material selected from the group consisting of materials having a relative dielectric permittivity ≥10 and materials having a relative dielectric permeability ≠1, the at least one ceramic dielectric inclusion embedded in a dielectric host material selected from the group consisting of amorphous silica, titania, tantalates, pure alumina, admixtures thereof, and an organic media such that the composite dielectric body has an effective permittivity ≥4;
a metallization layer adjacent the composite dielectric body and including a
ground plane and at least one contact pad; and
at least one electrically conductive element disposed parallel to the metallization layer and electrically connected with the at least one contact pad, each conductive element disposed relative to the composite dielectric body such that the conductive element is resonant over a band of frequencies and has a length that is ≤50% of the length that would be required to maintain the same resonance without the composite dielectric body,
wherein the ground plane comprises:
a ground plane dielectric body having a first surface and a second surface;
an electrical ground plane adjacent the first surface of the ground plane dielectric body; and
a periodic array of capacitor pads disposed at the second surface of the ground plane dielectric body and electrically shorted through the ground plane dielectric body, the array having a uniform periodicity and a spacing between the capacitor pads such that a desired phase shift will be induced in a reflected E field component of an electromagnetic wave incident upon the ground plane and having a frequency within a bandgap range of frequencies.
10. The module of claim 9 , wherein the induced phase shift is 0° when the incident electromagnetic wave has a center frequency within the bandgap range and substantially coincident with a peak frequency of the radiation profile of one or more of the at least one electrically conductive elements.
11. The module of claim 9 , wherein:
the at least one electrically conductive element comprises a plurality of antenna elements having distinct operational frequencies within the bandgap range; and
the induced phase shift is ≤±90°.
12. The module of claim 9 , wherein the induced phase shift is ≤±45°.
13. The module of claim 9 , wherein the ground plane dielectric body comprises:
a host material body having a loss tangent that is ≤3×10 −3 ; and
at least one ground plane ceramic dielectric inclusion embedded within the host material body.
14. The module of claim 13 , wherein the at least one ground plane ceramic dielectric inclusion is arranged in a layered configuration.
15. The module of claim 13 , wherein the at least ground plane ceramic dielectric inclusion comprise high-k inclusion having a relative permittivity ≥10, such that the ground plane dielectric body has an effective relative permittivity of at least 4 and a loss tangent less than about 8×10 −3 .
16. The module of claim 9 , wherein the ground plane dielectric body comprises a bulk layer composed of at least one material selected from amorphous silica and pure alumina.
17. The module of claim 16 , wherein the ground plane dielectric body further comprises at least one ground plane ceramic inclusion having a relative permeability ≠1, such that the ground plane dielectric body imparts a bandgap range of frequencies that is greater than the bandgap range of frequencies permissible without said high-μ ground plane ceramic inclusions.