Composition and bonding structure of boron nitride B1−xNx thin films grown by ion-beam assisted evaporation

► Boron nitrde B1−xNx (0 < x < 0.6) thin films grown by ion-beam assisted deposition. ► Atom-ion ratio, sticking coefficient, deposition rate in connection with composition. ► Bonding structure investigated by X-ray absorption and infrared spectroscopies. ► N-rich BN with graphitic-like structure and embedded N2 molecules. ► B-rich B13N2 phase consists of B12 icosahedral units linked by N-B-N linear chains.