Zero-bias high-responsivity high-bandwidth top-illuminated germanium p–i–n photodetectors

• 作 者: 李冲 薛春来 刘智 成步文 李传波 王启明
• 机 构: State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of
• 出 处: Chinese Physics B
• 发表日期: 2014年03期
• 关键词: bandwidth photodetector saturation collection insulator diameters magnitude leak

We report efficient zero-bias high-speed top-illuminated p–i–n photodiodes(PDs) with high responsivity fabricated with germanium(Ge) films grown directly on silicon-on-insulator(SOI) substrates. For a 15 μm-diameter device at room temperature, the dark current density was 44.1 mA/cm2at-1 V. The responsivity at 1.55 μm was 0.30 A/W at 0 V. The saturation of the optical responsivity at 0 V bias revealed that this photodetector allows a complete photo-generated carrier collection without bias. Although the 3-dB bandwidth of the 15-μm-diameter detector was 18.8 GHz at the reverse bias of 0 V, the detector responsivity was improved by one order of magnitude compared with that reported in the literature.Moreover, the dark current of the detector was significantly reduced.

We report efficient zero-bias high-speed top-illuminated p-i-n photodiodes (PDs) with high responsivity fabricated with germanium (Ge) films grown directly on silicon-on- insulator (SOI) substrates. device at room temperature, the dark current density was 44.1 mA / cm2at-1 V. The responsivity at 1.55 μm was 0.30 A / W at 0 V. The saturation of the optical responsivity at 0 V bias that that photodetector allows a complete photo -generated carrier collection without bias. Although the 3-dB bandwidth of the 15-μm-diameter detector was 18.8 GHz at the reverse bias of 0 V, the detector responsivity was improved by one order of magnitude compared with that reported in the literature. Moreover, the dark current of the detector was significantly reduced.