US 11,886,003 B2
Optical waveguide
Koji Takeda, Tokyo (JP); Shinji Matsuo, Tokyo (JP); and Hidetaka Nishi, Tokyo (JP)
Assigned to Nippon Telegraph and Telephone Corporation, Tokyo (JP)
Appl. No. 17/432,317
Filed by Nippon Telegraph and Telephone Corporation, Tokyo (JP)
PCT Filed Apr. 2, 2020, PCT No. PCT/JP2020/015160
§ 371(c)(1), (2) Date Aug. 19, 2021,
PCT Pub. No. WO2020/213412, PCT Pub. Date Oct. 22, 2020.
Claims priority of application No. 2019-077604 (JP), filed on Apr. 16, 2019.
Prior Publication US 2022/0171129 A1, Jun. 2, 2022
Int. Cl. G02B 6/12 (2006.01); G02B 6/036 (2006.01)
CPC G02B 6/12009 (2013.01) [G02B 6/036 (2013.01); G02B 2006/12061 (2013.01)] 6 Claims
OG exemplary drawing
 
1. An optical waveguide comprising:
a core disposed over a clad layer, wherein the clad layer is disposed over a semiconductor substrate, wherein the core is made of a first semiconductor material, and wherein the core has a rectangular shape in a cross-sectional view;
a spacer layer over the core, wherein the spacer layer comprises an insulator material and directly contacts a top surface of the core, sidewalls of the core, and a top surface of the clad layer; and
a slab layer disposed over and directly contacting the spacer layer, wherein the slab layer is configured to be optically coupled to the core, wherein the slab layer is made of a second semiconductor material, and wherein the first semiconductor material is a compound semiconductor material, and wherein the second semiconductor material is silicon.