This article ETU-LINK will take you to understand some innovative changes in silicon optical technology in the optical transceiver industry. Silicon optical technology, simply say is "optical substitution electricity", by integrating a large number of optical devices into a single silicon optical chip to greatly reduce the size of the optical module, simplify the design and production of optical modules. Silicon optical technology can be combined with integrated circuit technology to finally achieve the integration of optical chips and electrical chips to achieve optical interconnection between chips and chips and even inside chips. Silicon light technology has the outstanding advantages of high connection speed, low power consumption, high rate, compact structure, etc., and can be said to be the key technology to solve the bottlenecks in terms of power consumption, rate and volume faced by the information network.

The traditional optical module adopts a discrete structure, and the optical chip is aligned and coupled with the optical fiber through a series of passive coupling devices to complete the optical path packaging. The entire packaging process requires more materials and labor costs, while the packaging and testing processes are more complex, the packaging process automation rate is low, and the optical module needs to be manually aligned and coupled one by one in the test, and the time cost and labor cost are higher.

Silicon light using the traditional semiconductor industry is very mature silicon wafer processing technology, the use of etching process on the silicon substrate can quickly process large-scale waveguide devices, the use of epitaxial growth and other processing processes, can prepare modulators, receivers and other key devices, and finally achieve a high degree of integration of modulators, receivers and passive optics.

Compared with the traditional discrete devices, the traditional process needs to package the electrical chip, optical chip, lens, alignment component, optical fiber end face and other devices in turn, the silicon light volume is greatly reduced, the material cost, chip cost, packaging cost are expected to be further optimized, at the same time, silicon optical technology can be tested in batches through wafer testing and other methods, and the test efficiency is significantly improved.

At present, chip-level devices that can be matured based on silicon optical process can be processed, mainly including optical waveguides, combined wave-splitter devices, external modulation devices, APD receivers, etc. However, the design and process routes of mainstream manufacturers are still quite different, there are a variety of technical routes, from this point of view, it can also be seen that silicon light technology is still in the early stage of the development of a hundred schools of thought, the most cost-effective and technical stability of the program has not yet stood out, silicon light technology still needs a period of precipitation and development, in order to focus on the final winning mainstream technology, and then to a greater extent to play the scale effect of the CMOS process, cost and yield can continue to optimize. Silicon optical chip technology is relatively mature, but from the chip to the optical module, there are still many technical difficulties in the packaging process, and the package yield and cost still need to be optimized.