Chemical vapor deposition of tantalum nitride with tert-butylimino tris(diethylamino) tantalum and atomic hydrogen

X-ray photoelectron spectroscopy (XPS) has been used to study the reaction of tert-butylimino tris(diethylamino) tantalum (TBTDET) with atomic hydrogen on SiO2 and organosilicate glass (OSG) substrates. The results on both substrates indicate that, at 300 K, TBTDET partially dissociates, forming Ta-O bonds with some precursor still attached. Subsequent bombardment with atomic hydrogen at 500 K results in stoichiometric TaN formation, with a Ta(4f7/2) feature at binding energy 23.2 eV and N(1s) at 396.6 eV, leading to a TaN phase bonded to the substrate by Ta-O interactions. Subsequent depositions of the precursor on the reacted layer on SiO2 and OSG followed by atomic hydrogen bombardment result in increased TaN formation. These results indicate that TBTDET and atomic hydrogen may form the basis for a low-temperature atomic layer deposition (ALD) process for the formation of ultraconformal TaNx or Ru/TaNx barriers.