Avalanche photodiodes on silicon photonics

Silicon photonics technology has drawn significant interest due to its potential for compact and high-performance photonic integrated circuits.The Ge-or III-V material-based avalanche photodiodes integrated on silicon photonics provide ideal high sensitivity optical receivers for telecommunication wavelengths.Herein,the last advances of monolithic and hetero-geneous avalanche photodiodes on silicon are reviewed,including different device structures and semiconductor systems.

Mechanisms of enhanced sub-bandgap absorption in high-speed all-silicon avalanche photodiodes

All-silicon (Si) photodiodes have drawn significant interest due to their single and simple material system and perfect compatibility with complementary metal-oxide semiconductor photonics. With the help from a cavity enhancement effect, many of these photodiodes have shown considerably high responsivity at telecommunication wavelengths such as 1310 nm, yet the mechanisms for such high responsivity remain unexplained. In this work,an all-Si microring is studied systematically as a photodiode to unfold the various absorption mechanisms.At-6.4 V, the microring exhibits responsivity up to0.53 A∕W with avalanche gain, a 3 dB bandwidth of25.5 GHz, and open-eye diagrams up to 100 Gb/s. The measured results reveal the hybrid absorption mechanisms inside the device. A comprehensive model is reported to describe its working principle, which can guide future designs and make the all-Si microring photodiode a promising building block in Si photonics.

64 Gb/s low-voltage waveguide SiGe avalanche photodiodes with distributed Bragg reflectors

We demonstrate low-voltage waveguide silicon-germanium avalanche photodiodes(APDs)integrated with distributed Bragg reflectors(DBRs).The internal quantum efficiency is improved from 60%to 90%at 1550 nm assisted with DBRs while still achieving a 25 GHz bandwidth.A low breakdown voltage of 10 V and a gain bandwidth product of near 500 GHz are obtained.APDs with DBRs at a data rate of 64 Gb/s pulse amplitude modulation with four levels(PAM4)show a 30%–40%increase in optical modulation amplitude(OMA)compared to APDs with no DBR.A sensitivity of around-13 d Bm at a data rate of 64 Gb/s PAM4 and a bit error rate of 2.4×10^-4 is realized for APDs with DBRs,which improves the sensitivity by^2 d B compared to APDs with no DBR.

High speed optical modulation in Ge quantum wells using quantum confined stark effect

我们集中于 SiGe 材料免职，为高速度的探查垫的寄生电容的最小化，低电压和高对比的优化比率操作。设备制造为标准 Si 电子学基于过程并且对大量生产合适。我们量监禁和限制量的空效果(QCSE ) 的现在的观察在有在 Si 底层上种的 SiGe 障碍的 Ge 量井(QW ) 的 electroabsorption。尽管 Ge 是一个间接差距半导体，产生效果作为至少作为清楚、强壮在类似的波长在典型 III-V QWstructures 看。我们也表明了一个调节的人，与在大约 10 GHz 的多达 3.5 GHz， 2.5 V 的小开车电压和调整带宽的眼睛图。最后，在极端快的激光刺激下面的搬运人动力学和高速度的光电流反应被调查。