US 12,007,667 B2
Method for fabrication of ridge waveguides
Lewis Glynn Carpenter, Southampton (GB); Sam Adam Berry, Southampton (GB); Corin Barry Edmund Gawith, Southampton (GB); and Peter George Robin Smith, Southampton (GB)
Assigned to University of Southampton, Southampton (GB)
Appl. No. 17/619,355
Filed by University of Southampton, Southampton (GB)
PCT Filed Jun. 17, 2020, PCT No. PCT/GB2020/051459
§ 371(c)(1), (2) Date Dec. 15, 2021,
PCT Pub. No. WO2020/254799, PCT Pub. Date Dec. 24, 2020.
Claims priority of application No. 1908764 (GB), filed on Jun. 19, 2019.
Prior Publication US 2022/0299840 A1, Sep. 22, 2022
Int. Cl. G02F 1/377 (2006.01); B26D 3/12 (2006.01); C23C 14/02 (2006.01); C23C 14/18 (2006.01); C23C 14/34 (2006.01); C23C 14/58 (2006.01); G02F 1/35 (2006.01); G02F 1/355 (2006.01)
CPC G02F 1/3775 (2013.01) [B26D 3/12 (2013.01); C23C 14/021 (2013.01); C23C 14/185 (2013.01); C23C 14/34 (2013.01); C23C 14/5806 (2013.01); G02F 1/3525 (2013.01); G02F 1/3551 (2013.01); G02F 1/3558 (2013.01); G02F 2202/20 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method for fabricating an optical waveguide, the method comprising:
providing a sample of lithium niobate doped with magnesium oxide and having at least one grating of periodic domain inversion defined therein;
applying a layer of metallic zinc to a surface of the sample over the at least one grating using sputter deposition;
heating the sample in an atmosphere of pure oxygen to cause the zinc to indiffuse into the lithium niobate to form a waveguiding layer of increased refractive index under the surface of the sample; and
using a dicing blade to cut two substantially parallel channels along a length direction of the at least one grating, to define a ridge waveguide between the two channels.