Integrated Optical Devices in LiNbO 3

Abstract

Integrated optoelectronic devices are key components in fiber optic communication, sensor, and network systems (1,2,3). Integrated optoelectronic waveguide devices have been fabricated in a variety of substrates such as glass, silicon, compound semiconductors, and electro optic crystals. Compound semiconductors have shown promise in the fabrication of laser diodes and detectors and possibly even monolithic integration of optoelectronic components. Materials such as glass and silicon have the potential to yield low cost and low performance multimode coupler and interconnect devices. The electro optic property of LiNb03 makes it attractive for applications in optical switching and modulation in single mode optical fiber communication and sensor systems. Numerous research papers have been written in the last fifteen years outlining the performance of LiNb03 based devices. Typical devices are a)phase modulator, b)amplitude modulator, c)switch. These devices depend on the electro optic effect in which the application of an external field changes the refractive index in the crystal and thereby modulates the phase of the guided beam in the waveguide. There are manufacturing problems to be solved before these devices can become a commercial reality. The manufacturing technology for these devices utilizes microfabrication methods developed for silicon integrated circuits and as a result has the potential to yield low manufacturing costs due to the economy of mass producing these devices in a 3 inch wafer.