As telecom networks increase in complexity there is a need for systems capable of manage numerous optical signals. Many of the channel-manipulation functions can be done more effectively in the optical domain. MEMS devices are especially well suited for this functions since they can offer large number of degrees of freedom in a limited space, thus providing high levels of optical integration.
We have designed, fabricated and tested optical MEMS devices at the core of Optical Cross Connects, WDM spectrum equalizers and Optical Add-Drop multiplexors based on different fabrication technologies such as polySi surface micromachining, single crystal SOI and combination of both. We show specific examples of these devices, discussing design trade-offs, fabrication requirements and optical performance in each case.
Recently, optical MEMS devices have gained considerable attention in the telecommunications industry -- particularly in the optical networking and switching arenas. Since optical MEMS are micro-systems which rely on high precision optics, electronics and mechanics working in close concert, these emerging devices pose some unique packaging challenges yet to be addressed by the general packaging industry. Optical MEMS packages often are required to provide both optical and electrical access, hermeticity, mechanical strength, dimensional stability and long-term reliability. Hermetic optical access necessitates the use of metallized and anti- reflection coated windows, and ever-increasing electrical I/O count has prompted the use of higher density substrate/package technologies. Taking these requirements into consideration, we explore three ceramic packaging technologies, namely High Temperature Co-fired Ceramic (HTCC), Low Temperature Co-fired Ceramic (LTCC) and thin-film ceramic technologies. In this paper, we describe some optical MEMS packages designed using these three technologies and discuss their substrate designs, package materials, ease of integration and assembly.
Micro-optoelectromechanical systems (MOEMS) having valuable performance, size, and cost attributes offer novel solutions to the design of lightwave network elements. We will discuss the new challenges that realizing these benefits presents to the field of photonic packaging.
Local access fiber optic systems and distributed gain fiber amplifier systems require low-cost and highly stable laser diode packages with high coupling efficiencies. These systems may use uncooled packaged lasers from the central office to the subscriber units in discrete or integrated transceiver packages. Low cost and high volume manufacturing technologies must be developed in order to produce these laser packages. A simple alternative to existing technologies is described in this paper. AT&T Bell Laboratories has been developing silicon optical bench (SiOB) technology for use as an integrated packaging platform for lasers, photodetectors and passive optical components. In this paper we describe an integrated optical sub-assembly for use in high volume and low cost laser packaging. The assembly integrates bond sites for a laser, a backface monitor photodetector and a metallized lensed fiber onto a single silicon optical sub-assembly. The approach allows for low cost batch processing, assembly and testing of components using the silicon wafer as a carrier and the use of automated pick and place machines for assembly.