Hi Iván Enrique García Balderas

If it's only to get sure the presence of your dopant, UV-VIS spectroscopy may help you, you can get the band gap of your SiO before and after doping, additionally Raman spectroscopy could give you information about the disorder on the crystal lattice produced by the dopant.

Regards.

Dear Ivan,

Raman spectroscopy, Photoluminescence and Fourier transform infrared (FTIR) are good options to characterize your material. See for example:

Article Characterization of fluorine-doped silicon dioxide film by R...

Article Intense Blue–White Luminescence from Carbon-Doped Silicon-Ri...

https://iopscience.iop.org/article/10.1088/0256-307X/17/12/020/meta

Kind regards,

Julian

You can use UV-visible, XRD, and EDX for the information about the doping of a material

If you doped anything in the host material then u will get a feasible change in optical properties of host material. Therefore, you can performed any optical characterization to observed this diversity.

Iván Enrique García Balderas Depending on the level of doping something as simple as refractive index determination could work.

Iván Enrique García Balderas SEM or TEM- EDX will be helpful. Other than optical ICP-AES/ OES will be helpful.

Ultimately what type and amount of material you are doping are important before choosing any method.