Systems and approaches for silicon germanium thickness and composition determination using combined XPS and XRF technologies are described. In an example, a method for characterizing a silicon germanium film includes generating an X-ray beam. A sample is positioned in a pathway of said X-ray beam. An X-ray photoelectron spectroscopy (XPS) signal generated by bombarding said sample with said X-ray beam is collected. An X-ray fluorescence (XRF) signal generated by bombarding said sample with said X-ray beam is also collected. Thickness or composition, or both, of the silicon germanium film is determined from the XRF signal or the XPS signal, or both.