Optical response of channel waveguides in silicate glass created via ion implantation with optical barriers of varying thickness

Channel waveguides have been fabricated through ion implantation combined with photolithography in three types of silicate glass of diverse composition. The range of the implanted ions was different. Channel waveguide was formed by single- and multi-energy C + -ion implantation with different ion fluences, resulting in 1 × 10 16 cm −2 . The multi-energy implantation processes were performed at energies ranging from 0.8 to 1.6 MeV to establish a 1-µm wide barrier for the optical signal, positioned approximately 2 µm below the sample surface. For a precise methodology, Rutherford backscattering spectroscopy (RBS) was initially employed to ascertain the composition of the photoresist mask and, in conjunction with X-ray fluorescence (XRF) analysis, to determine the composition of the glass prior to ion implantation. Subsequently, the dimensions of the photoresist mask, glass compositions, and the derived glass-density values were utilised for SRIM simulations of the projected range of the C + ion. This led to the creation of channel waveguides and, alternatively, the standard planar waveguides. The range depth of the implanted ions (2.6 μm) and the waveguide-formation depth calculated (3.0 μm) using m-line spectroscopy were in good agreement. In the silicate glass with the highest Si content, the deepest range of carbon ions was SRIM-simulated, and optical modes (TE 0 and TE 1 ) were demonstrated at the wavelength of 473 nm. The increase in the refractive index corresponded to the value of 0.0168 for 473 nm. The effect of glass composition on the waveguide’s fabrication was discussed. In addition, there was an evident difference between multi- and single-energy implantation processes. When an optical signal with the wavelength of 473 nm was introduced into the sample, only one mode was propagated for the single-energy implantation of C + ions, whereas two modes were observed for the multi-energy implantation. The possibility of using multi-energy ion implantation for the controlled preparation of optical waveguides in glass has been demonstrated.