FORMING WAVEGUIDES AND HEAT TRANSFER ELEMENTS IN PRINTED CIRCUIT BOARDS
A method is provided for forming waveguides in a PCB. The method may include forming an opening in a PCB core comprising a plurality of conductive layers interleaved with a plurality of insulating layers, the opening extending from a first side of the PCB core to a second side of the PCB core. The method may also include filling the opening with metal. The method may also include forming a cavity enclosed by sidewalls by removing a first portion of the filled opening, the cavity extending from the first side of the PCB core to the second side of the PCB core. A second portion of the filled opening is a heat transfer element configured to transfer heat from the first side of the PCB core to the second side of the PCB core. The at least one waveguide is embedded within the heat transfer element and configured for transmitting signals from the first side to the second side.
1 . A method for forming waveguides in a PCB, the method comprising:
forming an opening in a PCB core comprising a plurality of conductive layers interleaved with a plurality of insulating layers, the opening extending from a first side of the PCB core to a second side of the PCB core;
filling the opening with metal; and
forming a cavity enclosed by sidewalls by removing a first portion of the filled opening, the cavity extending from the first side of the PCB core to the second side of the PCB core,
wherein a second portion of the filled opening is a heat transfer element configured to transfer heat from the first side of the PCB core to the second side of the PCB core,
wherein the at least one waveguide is embedded within the heat transfer element and configured for transmitting signals from the first side to the second side.
2 . The method of claim 1 , wherein the cavity forms a waveguide configured to transfer signals from a first side to a second side.
3 . The method of claim 1 , wherein the removing of a first portion of the filled opening is done by etching.
4 . The method of claim 1 , wherein the removing of a first portion of the filled opening is done by machining, lasering, etching or any combination thereof.
5 . The method of claim 1 , wherein the sidewalls of the formed cavity are plated.
6 . The method of claim 1 , wherein the sidewalls are substantially perpendicular to the first side and the second side of the PCB core.
7 . The method of claim 1 , further comprising forming lips extending from the sidewalls of the cavity above the top surface of the PCB by pattern plating.
8 . The method of claim 1 , further comprising:
forming outer circuitry of the PCB by etching; and
applying a solder mask to the outer circuitry of the PCB.
9 . The method of claim 1 , wherein the filling the opening with a metal comprises plating the metal into the opening or inserting a metal coin into the opening.
10 . The method of claim 1 , wherein the cavity of the at least one waveguide comprises a cross-section having a rectangular shape configured for linear polarization.
11 . The method of claim 1 , wherein the cavity of the at least one waveguide comprises a cross-section having an oval shape configured for circular polarization.
12 . The method of claim 1 , wherein the metal comprises copper.
13 . The method of claim 1 , wherein the metal comprises a metallic nano-paste.
14 . A PCB comprising:
a PCB core having a first side and a second side opposite to the first side;
a chip mounted on the first side of the PCB core;
a heat transfer element embedded in the PCB core, the heat transfer element comprising a bulk of conductive material and extending from the first side of the PCB core to the second side of the PCB; and
at least one waveguide comprising a cavity enclosed by sidewalls perpendicular to the first side and the second side of the PCB core, the cavity extending from the first side of the PCB core to the second side of the PCB core,
wherein the at least one waveguide is embedded within the heat transfer element and configured for transmitting signals from the first side to the second side or receiving signals from the second side to the first side,
wherein the heat transfer element is configured to transfer heat generated from the chip from the first side of the PCB core to the second side of the PCB core.
15 . The PCB of claim 14 , further comprising lips extending from the sidewalls above a top surface of the PCB from the first side of the PCB core.
16 . The PCB of claim 14 , wherein the cavity of the at least one waveguide comprises a cross-section having a rectangular shape configured for linear polarization.
17 . The PCB of claim 14 , wherein the cavity of the at least one waveguide comprises a cross-section having an oval shape configured for circular polarization.
18 . The PCB of claim 14 , wherein the heat transfer element comprises a metal coin embedded into the PCB core or a plated metal.
19 . The PCB of claim 14 , wherein the PCB comprising a plurality of conductive layers interleaved with a plurality of insulating layers.
20 . The PCB of claim 14 , further comprising outer circuitry on the first side of the PCB core for signal routing.
21 . A PCB comprising:
a PCB core having a first side and a second side opposite to the first side;
a chip mounted on the first side of the PCB core;
a heat transfer element embedded in the PCB core, the heat transfer element comprising a bulk of conductive material and extending from the first side of the PCB core to the second side of the PCB; and
at least one waveguide comprising a cavity enclosed by sidewalls perpendicular to the first side and the second side of the PCB core, the cavity extending from the first side of the PCB core to the second side of the PCB core,
wherein the heat transfer element comprises a first portion connecting to a second portion, the first portion being near the first side of the PCB core, and the second portion being near the second side of the PCB core and extending outward laterally from the sidewalls of the at least one waveguide such that the second portion of the heat transfer element comprises a larger heat transferring area than the first portion of the heat transfer element.
22 . The PCB of claim 21 , wherein the at least one waveguide is embedded within the heat transfer element and configured for transmitting signals from the first side to the second side or receiving signals from the second side to the first side, wherein the heat transfer element is configured to transfer heat generated from the chip from the first side of the PCB core to the second side of the PCB core,