Design and analysis of an optical waveguide tap for silicon CMOS circuits

A compact low-loss optical tap technology is critical for the incorporation of optical interconnects into mainstream complementary metal-oxide-semiconductor (CMOS) processes. For this work, an effort has been made to establish an optimal integrated optical tap design in terms of optical loss, bandwidth, economy, and process compatibility with multimetal layer CMOS circuits. A new device, which is based on a variation of the multimode interference effect, has been found to be especially promising. Two-dimensional (2-D) and three-dimensional (3-D) simulation results show low excess optical loss (