Silicon-Based Microphotonics and Integrated Optoelectronics

Abstract

The need for integrated optical interconnects in electronic systems is derivedfrom the cost and performance of electronic systems. If we examine the cost of all interconnects, it becomes apparent that there is an exponential growth in cost per interconnect with the length of the interconnect. A remarkable feature of interconnect cost is that the exponential relation holds over all length scales—from the shortest interconnects on a chip to the longest interconnects in global telecommunications networks. Longer interconnects are drastically more expensive, and these costs are ultimately related to the labor cost associated with each interconnect. Given this economic pressure, it is not surprising that there is a driving force to condense more functions locally on the same chip, board, or system. In condensing these functions, the number of long interconnects are decreased and the overall cost of the electronic system decreases dramatically. A specific glaring example of this driving force is Si complementary-metal-oxide-semiconductor (CMOS) technology, especially the case of microprocessors. In the Si microprocessor case, the flood gates to interconnect condensation were opened and the miraculous trend of lower cost for exponentially increasing performance was revealed.