Monolithically Integrated MESFET Devices on a High-Speed Silicon Photonics Platform

We present the design and fabrication of complimentary metal-semiconductor field-effect transistors (MESFETs) monolithically integrated on a high-speed silicon photonics platform. The transistors were built in an existing silicon photonics process without any additional process steps or modifications to maintain consistent photonics performance. The MESFETs showed a threshold voltage of -1.4 and 2.0 V for NMES and PMES, respectively. The NMES transconductance was measured to be 46.4 μS/μm, and the cutoff frequency was shown to be 2.2 GHz. Transistors of this design can be simply integrated into silicon photonics platforms for on-chip feedback circuits.