MOCVD Growth and Fabrication of High Power MUTC Photodiodes Using InGaAs-InP System

• Main Authors: Singh, Nandan, Ho, Charles Kin Fai, Tina, Guo Xin, Mohan, Manoj Kumar Chandra, Lee, Kenneth Eng Kian, Wang, Hong, Lam, Huy Quoc
• Other Authors: Temasek Laboratories
• Format: Article
• Language: English
• Published: 2016
• Subjects: Antireflection coatings; Device fabrications
• Online Access: https://hdl.handle.net/10356/81535; http://hdl.handle.net/10220/39575
• Institution: Nanyang Technological University

We report charge-compensated modified uni-traveling-carrier photodiodes (MUTC-PDs) with high photocurrent and fast response, grown using liquid group-V precursor, in an AIXTRON MOCVD system. The liquid group-V precursors involve less toxicity with better decomposition characteristics. Device fabrication is completed with standard processing techniques with BCB passivation. DC and RF measurements are carried out using a single mode fiber at 1.55 μm. For a 24-μm-diameter device (with diode ideality factor of 1.34), the dark current is 32.5 nA and the 3-dB bandwidth is ≫20 GHz at a reverse bias of 5 V, which are comparable to the theoretical values. High photocurrent of over 150.0 mA from larger diameter (>60 μm) devices is obtained. The maximum DC responsivity at 1.55 μm wavelength is O.51 A/W without antireflection coating. These photodiodes play a key role in the progress of the future THz communication systems.