垂直入射鍺光偵測器的臨界耦合分析

Critically coupled Germanium photodetector under vertical illumination

周擎暘(Ching-Yang Chou)

指導教授 ： 那允中

國立清華大學/電機資訊學院/光電工程研究所/碩士(2013年)

摘要

我們設計一個高效率－頻寬乘積(EBP)的PIN鍺光偵測器，並將光纖耦合進環形共振腔的“臨界耦合”現象，運用在元件上，使所有入射光能量被鎖進共振腔中，大幅提高鍺的吸收效率，使得只需數百奈米厚度的鍺，就可以達到90%的量子效率，傳統上PIN鍺光偵測器，則需要數微米，並且因為厚度很薄，載子傳輸時間短，頻寬可以高達50GHz，但缺點是線寬只有 ，為了改善線寬太窄，容易受波長漂移影響而降低量子效率，我們運用了反色散關係鏡子，利用其特殊的反射相位趨勢，補償了因雷射不穩，導致波長偏離造成的相位損失，進一步達到平頂陡邊的高量子效率頻譜。

關鍵字

光偵測器 ； 臨界耦合 ； 共振腔增強PIN光偵測器 ； 反常色散關係鏡子

並列摘要

We design a High efficiency-bandwidth product(EBP) PIN Germanium photodector and use critical coupling theory to analysis our structure . It can lock all incident light in this photodector so significantly enhance Quantum efficiency result in only several hundreds of nanometer thickness but Quantum efficiency can exceed 90%.Because of a very thin depletion region, carrier spend a few transit time , and bandwidth can exceed 50GHz . Some disadvantage like linewidth is too narrow so if light source wavelength shift let Quantum efficiency drop significantly , To overcome this problem , we use anomalous dispersion mirror to compensate cavity total phase and realize flat-top Quantum efficiency.

並列關鍵字

Photodetector ； Resonant-Cavity-Enhanced ； Critical coupled ； anomalous-dispersion

參考文獻

1. Masini, G., et al., High-performance p-i-n Ge on Si photodetectors for the near infrared: from model to demonstration. Electron Devices, IEEE Transactions on, 2001. 48(6): p. 1092-1096.

2. High-performance Ge-on-Si photodetectors, J.L.L.C.K. Jurgen Michel1, Editor. 2010.

3. DeRose, C.T., et al., Ultra compact 45 GHz CMOS compatible Germanium waveguide photodiode with low dark current. Optics Express, 2011. 19(25): p. 24897-24904.

4. Yu, H.-Y., et al., High-Efficiency p-i-n Photodetectors on Selective-Area-Grown Ge for Monolithic Integration. Electron Device Letters, IEEE, 2009. 30(11): p. 1161-1163.

5. Joo, J., et al., High-sensitivity 10 Gbps Ge-on-Si photoreceiver operating at ? ~1.55 ?m. Opt. Express, 2010. 18(16): p. 16474-16479.