Monolithically Integrated High-Performance Ge-on-Si PIN Photodetectors with Nearly 60 GHz EO Bandwidth, 0.95 A/W Responsivity, <30 nA Dark Current and -36 dB Optical Return Loss Enabled by Ge Shape Optimization

We present optimized Ge shaping techniques that significantly reduce the back reflection of O-band Ge-on-Si photodetectors, achieving an optical return loss of -36dB in conjunction with ~60GHz 3-dB-EO-bandwidth, 0.95A/W responsivity and average dark current <30nA.