Silicon waveguide-integrated optical power monitor with enhanced sensitivity at 1550nm

We describe the fabrication and operation of an optical power monitor, monolithically integrated with a silicon-on-insulator rib waveguide. The device consists of a p+-v-n+ structure with a detection volume coincident with the single-mode supporting waveguide. Detection of optical signals at wavelengths around 1550nm is significantly enhanced by the introduction of midband-gap generation centers, which provide partial absorption of the infrared light. The most efficient device extracted 19% of optical power from the waveguide and showed a responsivity of 3mA∕W. These devices are fabricated using current standard processing technology and are fully compatible with silicon waveguide technology and integrated operational amplifier circuits.