Stress Induced Effects for Advanced Polarization Control in Silicon Photonics Components

Figure 6

(a) Optical image of a fabricated AWG. (b) Polarization-dependent wavelength shift Δλ as a function of the cladding thickness 𝑡_c, for AWGs fabricated using wet (waveguide top width 𝑊₁ = 1.1 𝜇m and bottom width 𝑊₂ = 3.8 𝜇m) and dry (𝑊₁ = 1.85 𝜇m and 𝑊₂ = 2.0𝜇m) etching to a depth of 𝐷 =1.47 𝜇m. The cladding stress is 𝜎_film = −320 MPa. Measured spectra for an SOI AWG. (c) Measured spectrum for an SOI AWG without the oxide upper cladding. (d) Compensated using a 0.6 𝜇m thick SiO₂ claddings with 𝜎_film = −320 MPa. TM (solid) and TE (dashed).