US 12,222,546 B2
Optical waveguide, method for manufacturing optical waveguide, and optical semiconductor device
Tomonari Sato, Tokyo (JP); Takahiko Shindo, Tokyo (JP); and Yuta Ueda, Tokyo (JP)
Assigned to NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo (JP)
Appl. No. 17/915,416
Filed by Nippon Telegraph and Telephone Corporation, Tokyo (JP)
PCT Filed Mar. 31, 2020, PCT No. PCT/JP2020/014859
§ 371(c)(1), (2) Date Sep. 28, 2022,
PCT Pub. No. WO2021/199297, PCT Pub. Date Oct. 7, 2021.
Prior Publication US 2023/0136090 A1, May 4, 2023
Int. Cl. G02B 6/13 (2006.01); G02B 6/12 (2006.01); G02B 6/122 (2006.01)
CPC G02B 6/131 (2013.01) [G02B 6/1225 (2013.01); G02B 2006/12078 (2013.01); G02B 2006/12128 (2013.01); G02B 2006/12173 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A method for manufacturing an optical waveguide comprising a semiconductor quantum well structure, wherein the optical waveguide comprises a first region in which the semiconductor quantum well structure is not disordered, a second region in which the semiconductor quantum well structure is disordered, and a third region provided between the first region and the second region, the method comprising:
forming a selective growth mask defining an opening portion in the third region in a surface of a crystal including the semiconductor quantum well structure, wherein a ratio between a width of the selective growth mask and a width of the opening portion varies continuously in a direction from the first region toward the second region over all of the third region;
selectively growing a semiconductor crystal in the opening portion;
removing the selective growth mask;
forming an annealing mask in the second region, the third region, and a part of the first region including an interface between the first region and the second region;
annealing the crystal including the semiconductor quantum well structure with the annealing mask formed thereon; and
removing the annealing mask.