X-Ray Characterization of Low-Thermal-Conductivity Thin-Film Materials

X-ray diffraction and imaging techniques at the Advanced Photon Source (APS) have been used to characterize PbSe/MoSe 2 and PbSe/WSe 2 thin films and multilayers. Diffraction measurements with area detectors were made to demonstrate the nanoscale coherence size of the layers both in-plane and perpendicular to the surface. Higher-resolution diffraction measurements that exploit the tunability of synchrotron radiation for anomalous scattering contrast have been used to accurately determine layer spacings in these multilayers. We also discuss opportunities in other new and emerging x-ray techniques, such as time-resolved studies during growth or processing, and present x-ray imaging capabilities that can be used to investigate thermoelectric thin-film materials.