게시판 최근논문

[Editors Pick] Current Optics and Photonics Vol. 3 no. 6 (2019 December)

한국광학회 hit 150 date 2021-04-05

Frequency Response Estimation of 1.3 µm Waveguide Integrated Vertical PIN Type Ge-on-Si Photodetector Based on the Analysis of Fringing Field in Intrinsic Region

Dongjun Seo1, Won-Bae Kwon2, Sung Chang Kim2, and Chang-Soo Park1 *

1 School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Korea
2 Honam Research Center, Electronics and Telecommunications Research Institute (ETRI), Gwangju 61012, Korea

 

 

 

Current Optics and Photonics  Vol. 3 No. 6 (2019 December) pp. 510-515
DOI: https://doi.org/10.3807/COPP.2019.3.6.510

 


 


Fig. 1  Photodetector structure diagrams-(a) perspective view; (b) front view; (c) top view.

 

 

Abstract

In this paper, we introduce a 1.3-µm 25-GHz waveguide-integrated vertical PIN type Ge-on-Si photodetector fabricated using a multi-project wafers service based on fringing field analysis in the depletion region. In general, 1.3-µm photodetectors fabricated using a commercial foundry service can achieve limited bandwidths because a significant amount of photo-generated carriers are located within a few microns from the input along the device length, and they are influenced by the fringing field, leading to a longer transit time. To estimate the response time, we calculate the fringing field in that region and the transit time using the drift velocity caused by the field. Finally, we compare the estimated value with the measured one. The photodetector fabricated has a bandwidth of 20.75 GHz at -1 V with an estimation error of <3 GHz and dark current and responsivity of 110 nA and 0.704 A/W, respectively.