Open AccessLow V_π Silicon photonics modulators with highly linear epitaxially grown phase shifters
Author(s) -
Saeed Sharif Azadeh,
Florian Merget,
Sebastián Romero-García,
Alvaro Moscoso-Mártir,
Nils von den Driesch,
Juliana Müller,
S. Mantl,
D. Buca,
Jeremy Witzens
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.023526
Subject(s) - materials science , phase shift module , optoelectronics , diode , optics , phase modulation , silicon photonics , photonics , modulation (music) , silicon , wafer , fabrication , epitaxy , phase (matter) , linearity , insertion loss , phase noise , electronic engineering , physics , nanotechnology , medicine , alternative medicine , engineering , pathology , layer (electronics) , quantum mechanics , acoustics
We report on the design of Silicon Mach-Zehnder carrier depletion modulators relying on epitaxially grown vertical junction diodes. Unprecedented spatial control over doping profiles resulting from combining local ion implantation with epitaxial overgrowth enables highly linear phase shifters with high modulation efficiency and comparatively low insertion losses. A high average phase shifter efficiency of VπL = 0.74 V⋅cm is reached between 0 V and 2 V reverse bias, while maintaining optical losses at 4.2 dB/mm and the intrinsic RC cutoff frequency at 48 GHz (both at 1 V reverse bias). The fabrication process, the sensitivity to fabrication tolerances, the phase shifter performance and examples of lumped element and travelling wave modulators are modeled in detail. Device linearity is shown to be sufficient to support complex modulation formats such as 16-QAM.