Low-Loss Buried-Heterostructure Optical Waveguide Based on Impurity-Free-Vacancy-Diffusion Quantum Well Intermixing

Low-Loss Buried-Heterostructure Optical Waveguide Based on Impurity-Free-Vacancy-Diffusion Quantum Well Intermixing

A new method for fabricating a high-quality buried-heterostructure optical waveguide using quantum well intermixing (QWI) has been demonstrated. By patterning a SiO<sub>2</sub> thin film on top of a multiple quantum well (MQW) heterostructure, rapid thermal annealing (RTA) could induce l...

Full description

Saved in:
Bibliographic Details
Main Authors: Yang-Jeng Chen, Rih-You Chen, Chih-Hsien Chen, Yu-Hung Lin, Cong-Long Chen, Po-Yun Wang, Yen-Hsiang Chang, Yi-Jen Chiu
Format: Article
Language:English
Published: IEEE 2020-01-01
Series:IEEE Photonics Journal
Subjects:
Quantum well intermixing
low loss waveguide
buried waveguide
electroabsorption modulator (EAM).
Online Access:https://ieeexplore.ieee.org/document/9024120/
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A new method for fabricating a high-quality buried-heterostructure optical waveguide using quantum well intermixing (QWI) has been demonstrated. By patterning a SiO<sub>2</sub> thin film on top of a multiple quantum well (MQW) heterostructure, rapid thermal annealing (RTA) could induce laterally local QWI, resulting in a bandgap blueshift and a simultaneous decrease in the refractive index. Both lateral bandgap and index engineering could be attained along the MQW plane, which could be used for a buried-heterostructure optical waveguide. Two SiO<sub>2</sub> strips with 3, 5 and 7&#x00A0;&#x03BC;m windows were fabricated for waveguide on a 1540&#x00A0;nm InGaAsP MQW sample. A 120&#x00A0;nm blueshift under the SiO<sub>2</sub> area was observed, leading to the index contrast of 0.07. Far-field optical diffraction measurements were also performed to yield angles of 13.9&#x00B0;, 12.8&#x00B0; and 10.6&#x00B0;. A narrower window resulted in a narrower optical waveguide width and exhibited a larger diffraction angle, suggesting that QWI defined the buried optical waveguide. In addition, an electroabsorption modulator was also made by buried waveguide. A &#x2212;10&#x00A0;dB low optical insertion loss and a 15 dB high extinction ratio in a 500&#x00A0;&#x03BC;m long waveguide were obtained, indicating that a buried heterostructure could be used for photonic devices and integration applications.
ISSN:1943-0655

Similar Items