Matching drive device for multi-beam optoelectronic arrays
An apparatus providing a phase-matched interface between a driver device and a multibeam optoelectronic device, such as a VCSEL array device, is disclosed as well as various methods for utilization and manufacturing of the same. The interface device includes an input adapted to interface with the driver device, an output to interface with the multibeam optoelectronic device, and a power splitter to electrically connect the output to the input. The output includes a plurality of output contacts that each interface with one optoelectronic device among the plurality of optoelectronic devices of the multibeam optoelectronic device via one transmission line among a plurality of transmission lines having a common electrical length. In embodiments, the power splitter is a resistor-based power splitter that adjusts an overall impedance of the power splitter at each “tee” junction or intersection to provide an impedance-matched interface.
1. An optoelectronic array device, comprising:
a plurality of optoelectronic devices;
a driver device for the plurality of optoelectronic devices;
an input adapted to interface with the driver device;
an output comprising a plurality of output contacts, each output contact among the plurality of output contacts adapted to interface with one optoelectronic device among the plurality of optoelectronic devices via one transmission line among a plurality of transmission lines having a common electrical length; and
a power splitter formed on a substrate stack electrically connecting the output to the input, wherein the input, the output and the power splitter provide a phase matched interface between the drive device and each of the plurality of optoelectronic devices among the plurality of optoelectronic devices.
2. The apparatus of claim 1 , wherein the substrate stack comprises a ground plane formed on a substrate and electrically isolating the power splitter from the substrate.
3. The apparatus of claim 1 , wherein the substrate stack comprises a first dielectric layer composed of a first dielectric material, the power splitter being formed on the first dielectric layer.
4. The apparatus of claim 3 , wherein the first dielectric material has a dielectric loss tangent of less than 0.01 at 1 gigahertz.
5. The apparatus of claim 3 , wherein each transmission line of the plurality of transmission lines has a width determined based upon a thickness of the first dielectric layer.
6. The apparatus of claim 1 , wherein the substrate stack comprises a conductor layer, the plurality of transmission lines being formed in the conductor layer.
7. The apparatus of claim 1 , wherein two or more output contacts among the plurality of output contacts are connected in parallel to the input.
8. The apparatus of claim 1 , wherein the power splitter further comprises a plurality of resistors, each resistor of the plurality of resistors having a common resistive value.
9. The apparatus of claim 8 , wherein the substrate stack comprises a resistive layer, the plurality of resistors being formed in the resistive layer.
10. The apparatus of claim 9 , wherein the resistive layer is formed on a second dielectric layer above the plurality of transmission lines.
11. The apparatus of claim 8 , wherein a width of each transmission line tapers from a first value to a second value in a region surrounding one resistor of the plurality of resistors based on a resistance value of the one resistor.
12. The apparatus of claim 1 , wherein the power splitter is a Wilkinson power splitter.
13. The apparatus of claim 1 , wherein the substrate stack is formed using thin-film deposition techniques.
14. An optoelectronic array device, comprising:
a plurality of optoelectronic devices formed on a substrate stack; and
an interface device formed on the substrate stack and providing a phase-matched interface between each of the plurality of optoelectronic devices and a driver device, the interface device comprising:
an input adapted to interface with the driver device;
an output comprising a plurality of output contacts, each output contact among the plurality of output contacts adapted to interface with one optoelectronic device among the plurality of optoelectronic devices via one transmission line among a plurality of transmission lines having a common electrical length; and
a power splitter electrically connecting the output to the input.
15. The optoelectronic array device of claim 14 , wherein the substrate stack comprises:
a ground plane formed on a substrate and electrically isolating the power splitter from the substrate;
a first dielectric layer formed on the ground plane, each transmission line of the plurality of transmission lines having a width determined based upon a thickness of the first dielectric layer; and
a conductor layer formed on the first dielectric layer, the plurality of transmission lines being formed in the conductor layer.
16. The optoelectronic array device of claim 15 , wherein the ground plane and the conductor layer forming the transmission lines are separately connected by bonded wires to an electronic package that can be soldered to a printed circuit board or directly to electrical contacts of the driver device.
17. The optoelectronic array device of claim 15 , wherein the ground plane and the conductor layer forming the transmission lines are separately connected by conductive vias in the substrate to conductive contact pads on a lower surface of the substrate that can be soldered to a printed circuit board or directly to electrical contacts of the driver device.
18. The optoelectronic array device of claim 14 , wherein the power splitter further comprises a plurality of resistors, each resistor of the plurality of resistors having a common resistive value.
19. The optoelectronic array device of claim 18 , wherein a width of each transmission line tapers from a first value to a second value in a region surrounding one resistor of the plurality of resistors based on a resistance value of the one resistor.
20. A method of manufacturing an optoelectronic array device, the method comprising:
providing a substrate;
forming a substrate stack on the substrate, the substrate stack collectively comprising an interface device configured to provide a phase matched interface between each of a plurality of optoelectronic devices and a driver device, the interface device comprising:
an input adapted to interface with the driver device;
an output comprising a plurality of output contacts, each output contact among the plurality of output contacts adapted to interface with one optoelectronic device among the plurality of optoelectronic devices via one transmission line among a plurality of transmission lines having a common electrical length; and
a power splitter electrically connecting the output to the input.
21. The method of claim 20 , wherein forming the substrate stack comprises:
forming a ground plane on the substrate, the ground plane electrically isolating the power splitter from the substrate;
forming a first dielectric layer on the ground plane, each transmission line of the plurality of transmission lines having a width determined based upon a thickness of the first dielectric layer; and
forming a conductor layer on the first dielectric layer, the plurality of transmission lines being formed in the conductor layer.
22. The method of claim 21 , wherein the power splitter further comprises a plurality of resistors, and wherein forming the substrate stack further comprises:
forming a second dielectric layer on the conductor layer; and
forming a resistive layer on the second dielectric layer, the plurality of resistors being formed in the resistive layer.