Passive Millimeter Wave Components on Lithium Niobate Substrates

The purpose of this project is to develop passive microwave components on LiNbO3 substrates. LiNbO3 is a transparent crystal commonly used in optical devices and SAW filters due to its excellent optical properties and piezoelectric effect. At microwave or millimeter wave frequencies, the dielectric constants of LiNbO3 are around 42 in optical axis and 26 in other axes. This is much higher than other common substrates used in microwave or millimeter wave devices. Since the sizes of passive components are proportional to wavelength, we expect the benefit of size reduction if LiNbO3 substrates are used. Antennas, couplers, bandpass filters and diplexers at ka band will be developed on LiNbO3 substrates to verify this concept and integrate with the components from other subproject to form a complete transceiver module. In optical frequency, the strong electro-optic effect of LiNbO3 is utilized to implement light modulators and Mach-Zehnder interferometer switches. Since light is also electromagnetic waves, the same principle of these devices can be applied to microwave and millimeter wave frequencies. We plan to implement ka band phase shifters and switches by the same principle to verify the concept.

Project ID:PB9511-0783
External Project ID:NSC95-2221-E182-080