Thermal stability of RuO2, BaxSr1-xTiO3/RuO2, and BaxSr1-xTiO3/Pt/Ti/SiO2 on Si(100)

Abstract

The thermal stability of RuO2/Si(100) films in air was studied using ex situ synchrotron x-ray scattering. The (110) textured RuO2 film showed good thermal stability due to the low surface and strain energies. However, the RuO2 films of high strain and surface energies were transformed to three-dimensional islands during annealing up to 800 degrees C. We also studied, during the post annealing process, the interface roughness of BaxSr1-xTiO3 (BST)/RuO2/Si(100) and BST/Pt/Ti/SiO2/Si(100) structures comparatively, using in situ synchrotron x-ray scattering. The interfaces of the BST/PuO2/Si were thermally stable up to 500 degrees C, and the deterioration of the interfaces above 500 degrees C was attributed to the crystallization of amorphous BST film. Meanwhile, the interfaces of the BST/Pt/Ti/SiO2/Si were significantly degraded even at the low temperature of 350 degrees C, mainly due to the formation of the Pt-Ti alloy and the Ti oxidation.