In:
Optics Letters, Optica Publishing Group, Vol. 45, No. 15 ( 2020-08-01), p. 4188-
Abstract:
A technology called self-aligned selective undercut dry etching processing has been demonstrated for fabricating a highly efficient hybrid optical spot size converter (SSC) on a Si-on-insulator (SOI) template. The process was based on a bonded wafer between the upper InP-based multiple quantum well heterostructure and the lower SOI substrate. After defining the mask on the upper InP-based ridge waveguide, C F 4 / O 2 dry reactive ion etching was then used for selective undercut etching of the Si material from the surrounding materials, forming a vertical waveguide coupler of the optical SSC. The lower waveguide, whose dimension is even smaller than the upper one, can thus be vertically self-aligned to the top ridge via an independent processing step. A laterally tapered waveguide ranging from 0.3 to 3 µm in width on the upper InP waveguide was fabricated. The phase-matching condition of the vertical coupler leads to a length of 45 µm and extracts 88% conversion efficiency. The selective undercut etching processing in III-V/SOI material provides a vertical self-alignment scheme for realizing compact and submicron scale heterogeneous integration in a Si photonics template.
Type of Medium:
Online Resource
ISSN:
0146-9592
,
1539-4794
Language:
English
Publisher:
Optica Publishing Group
Publication Date:
2020
detail.hit.zdb_id:
243290-0
detail.hit.zdb_id:
1479014-2
