US 12,405,422 B2
Cladding structure for semiconductor waveguide
Chan-Hong Chern, Palo Alto, CA (US)
Assigned to Taiwan Semiconductor Manufacturing Company, Ltd., Hsinchu (TW)
Filed by Taiwan Semiconductor Manufacturing Company, Ltd., Hsinchu (TW)
Filed on Aug. 25, 2022, as Appl. No. 17/895,342.
Prior Publication US 2024/0069278 A1, Feb. 29, 2024
Int. Cl. G02B 6/122 (2006.01); G02B 6/12 (2006.01); G02B 6/132 (2006.01); G02B 6/136 (2006.01)
CPC G02B 6/1223 (2013.01) [G02B 6/1228 (2013.01); G02B 6/132 (2013.01); G02B 6/136 (2013.01); G02B 2006/12195 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for forming a semiconductor structure, the method comprising:
depositing a first cladding layer along a first side of a semiconductor waveguide layer and over a device segment, a tapered segment, and a tip of the semiconductor waveguide layer, wherein tapered segment is between the device segment and the tip of the semiconductor waveguide layer;
etching the first cladding layer to remove the first cladding layer from over the device segment, wherein the first cladding layer remains over the tip and the tapered segment after the etching of the first cladding layer;
depositing a first dielectric layer over the first cladding layer and along the first side of the semiconductor waveguide layer;
depositing a second dielectric layer along a second side of the semiconductor waveguide layer, opposite the first side, and over the device segment, the tapered segment, the first cladding layer, and the first dielectric layer; and
depositing a second cladding layer along the second side of the semiconductor waveguide layer, beside the second dielectric layer, and over the first cladding layer, the tip, and the tapered segment,
wherein a difference between a refractive index of the semiconductor waveguide layer and a refractive index of the first cladding layer is less than a difference between the refractive index of the semiconductor waveguide layer and a refractive index of the first dielectric layer.