25 Gbps × four-channel chip-scale optical receiver operating at up to 85 °C with a temperature-compensation function

We successfully developed a 5 x 5 mm(2) chip-scale optical receiver using silicon photonics technology. The optical receiver was integrated with a 28 nm CMOS transimpedance-amplifier chip designed to have a temperature-compensation function to achieve stable operation at high temperatures. Error-free operations were demonstrated for signals of the 25 Gbps pseudorandom binary sequence 2(31) - 1 at 25 degrees C and 85 degrees C using the compensation function. The minimum sensitivities and transimpedance gains were -9.5 dBm and 76.6 dB Omega at 25 degrees C, and -8.9 dBm and 76.7 dB Omega at 85 degrees C, respectively. We also verified the uniform characteristics of the four channels of the receiver with a sensitivity variation of 0.2 dB. These stable operations at a high temperature, and the uniform characteristics of the four channels indicate that our receiver can be used for 100 Gbps (25 Gbps x four-channel) applications at high temperatures. (C) 2019 The Japan Society of Applied Physics