Optical device having dual microstrip transmission lines with a low-k material and a method of manufacture thereof
View Patent ↗The present invention provides an optical device. In one embodiment, the optical device includes an optical waveguide formed in or over a ridge located on a substrate. The optical device also includes a microstrip transmission line comprising a signal electrode and a ground electrode adjacent the ridge and a low-k dielectric material separating the signal and ground electrodes. The present invention also provides a method for making the optical device.
1. An optical device, comprising:
an optical waveguide formed over or in a ridge located on a substrate;
a microstrip transmission line comprising a signal electrode and a ground electrode adjacent said ridge; and
a low-k dielectric material separating said signal and ground electrodes,
wherein a length of said optical device is about 1 cm, when said device includes a capacitance loading of about 4 pF/cm, an operational bandwidth of at least about 40 GHz at −3 dB, and a modulation voltage (V π ) of about 2.5V or less.
2. An optical device, comprising:
an optical waveguide formed over or in a ridge located on a substrate;
a microstrip transmission line comprising a signal electrode and a ground electrode adjacent said ridge; and
a low-k dielectric material separating said signal and ground electrodes,
wherein said microstrip transmission line includes a plurality of electrode contacts located over said optical waveguide and having varying lengths.
3. A method of manufacturing an optical device, comprising:
forming an optical waveguide over or in a ridge located on a substrate;
forming a microstrip transmission line having a ground electrode and signal electrode adjacent said ridge, including locating a low-k material between said ground electrode and said signal electrode; and
manufacturing said optical device with a length of about 1 cm, when said device includes a capacitance loading of about 4 pF/cm, an operational bandwidth of at least about 40 GHz at −3 dB, and a modulation voltage (V π ) of about 2.5V or less.
4. A method of manufacturing an optical device, comprising:
forming an optical waveguide over or in a ridge located on a substrate; and
forming a microstrip transmission line having a ground electrode and signal electrode adjacent said ridge, including locating a low-k material between said ground electrode and said signal electrode, wherein forming said microstrip transmission line includes forming a plurality of signal electrode contacts located over said optical waveguide and having varying lengths.
5. An optical transmitter, comprising:
an optical source configured to generate an optical signal;
an optical modulator coupled to said optical source and configured to modulate said optical signal, said optical modulator including:
an optical waveguide formed over or in a ridge located on a substrate;
a microstrip transmission line comprising a signal electrode and a ground electrode adjacent said ridge; and
a low-k dielectric material separating said signal and ground electrodes; and
an optical fiber coupled to said optical modulator and configured to carry said modulated optical signal,
wherein a length of said optical modulator is about 1 cm, when said optical modulator includes a capacitance loading of about 4 pF/cm, an operational bandwidth of at least about 40 GHz at −3 dB, and a modulation voltage (V π ) of about 2.5V or less.
6. An optical transmitter, comprising:
an optical source configured to generate an optical signal;
an optical modulator coupled to said optical source and configured to modulate said optical signal, said optical modulator including:
an optical waveguide formed over or in a ridge located on a substrate;
a microstrip transmission line comprising a signal electrode and a ground electrode adjacent said ridge; and
a low-k dielectric material separating said signal and ground electrodes; and
an optical fiber coupled to said optical modulator and configured to carry said modulated optical signal,
wherein said microstrip transmission line includes a plurality of electrode contacts located over said optical waveguide and having varying lengths.
7. An optical device, comprising:
an optical waveguide formed over or in a ridge located on a substrate;
a microstrip transmission line adjacent said ridge and having ground and signal electrodes and a low-k material located therebetween; and
a plurality of electrode contacts located over said optical waveguide and having varying lengths.
8. The optical device as recited in claim 7 , wherein said varying lengths are arranged along a length of said optical waveguide in a manner selected from the group consisting of:
linearly;
exponentially; and
sinusoidally.
9. The optical device as recited in claim 7 wherein said signal electrode is formed over said substrate and said ground electrode.
10. The optical device as recited in claim 7 wherein a length of said optical device is about 1 cm, when said device includes a capacitance loading of about 4 pF/cm, an operational bandwidth of at least about 40 GHz at −3 dB, and a modulation voltage (V π ) of about 2.5V or less.
11. The optical device as recited in claim 9 wherein said optical device includes a parallel pair of micro strip transmission lines and optical waveguides.
12. The optical transmitter as recited in claim 11 wherein said optical device is a dual optical waveguide device and said parallel pair of microstrip transmission lines are dual microstrip transmission lines having a pair of parallel optical waveguides located therebetween.
13. The optical device as recited in claim 7 wherein said optical device is a modulator that forms at least a portion of an optical transmitter, further including an optical source optically coupled to said modulator.
14. A method of manufacturing an optical device, comprising:
forming an optical waveguide over or in a ridge located on a substrate; and
forming a microstrip transmission line having a signal electrode and ground electrode adjacent said ridge and including placing a low-k material therebetween; and
forming a plurality of electrode contacts located over said optical waveguide and having varying lengths.
15. The method as recited in claim 14 wherein forming a microstrip transmission line includes forming a signal electrode including a plurality of electrode contacts having varying lengths arranged along a length of said optical waveguide in a manner selected from the group consisting of:
linearly;
exponentially; and
sinusoidally.
16. The method as recited in claim 14 wherein forming a microstrip transmission line includes forming a signal electrode over said substrate and said ground electrode.
17. The method as recited in claim 14 , further including manufacturing said optical device with a length of about 1 cm, when said device includes a capacitance loading of about 4 pF/cm, an operational bandwidth of at least about 40 GHz at −3 dB, and a modulation voltage (V π ) of about 2.5V or less.
18. The method as recited in claim 14 wherein forming a microstrip transmission line includes forming a parallel pair of microstrip transmission lines and optical waveguides.
19. The method as recited in claim 18 wherein forming a parallel pair of microstrip transmission lines and optical waveguides includes forming a dual optical waveguide device wherein said parallel pair of microstrip transmission lines form parallel microstrip transmission lines having a pair of parallel optical waveguides located therebetween.