Zirconium diboride (ZrB2) is an important ceramic due to its extremely high melting temperature of 3245 degrees C and metallic electrical conductivity, properties that make it an ideal candidate thin film electrode material for high temperature electronics. In this report, thin films of varying B:Zr ratio ranging from 3-0.67 have been grown by e-beam evaporation from elemental sources. X-ray absorption spectra at the Zr K-edge were measured before and after annealing in ultra-high vacuum for 9 h at 1000 degrees C. Films with compositions near ZrB2 stoichiometry show X-ray absorption fine structure that can be well modeled by crystalline ZrB2 with a small portion of a coexisting tetragonal zirconia (t-ZrO2) phase. Films far from stoichiometry show substantial disorder beyond the nearest-neighbor distances, and after vacuum annealing exhibit high levels of oxidation. Contributions to the X-ray absorption fine structure from a pure Zr phase are very small compared to ZrB2 and t-ZrO2 phases. The fact that nearly stoichiometric (3 < B:Zr < 1.6) as-deposited amorphous films form the same crystalline ZrB2 nanostructure after annealing is particularly encouraging for high temperature thin film electronics applications, because it would allow the production of highly stable electrodes with e-beam evaporation without the need of any high temperature heating during film growth. (C) 2015 Elsevier B.V. All rights reserved.