Guanidinato-based precursors for MOCVD of metal nitrides (M x N: M = Ta,W)

• Published in: Surface & coatings technology Vol. 201; no. 22; pp. 9125 - 9130
• Main Authors: Rische, Daniel, Parala, Harish, Baunemann, Arne, Thiede, Tobias, Fischer, Roland
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Lausanne Elsevier B.V 25.09.2007; Elsevier
• Subjects: Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Gate electrodes; Guanidinato ligands; Materials science; Metal nitrides; Methods of deposition of films and coatings; film growth and epitaxy; MOCVD; Physics; Metal nitrides; Guanidinato ligands; MOCVD; Gate electrodes; CVD; Electrodes; Nitrides; Surface treatments
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2007.04.072

Refractory metal nitrides such as TaN and W x N are interesting candidates as novel gate electrodes in CMOS technology. MOCVD and, in particular, ALD are desirable deposition processes and the development of new complexes and the precursor chemistry plays a vital role. We are interested in fine-tuning the properties of key precursors by ligand variation and introducing the chelating all-nitrogen coordinating groups such as guanidinato and β-diketiminato ligands. Guanidinato ligand-based complexes of groups V and VI, especially Ta, and W are interesting precursors for MOCVD and ALD of respective metal nitride thin film growth. As a representative example, evaluation of Ta- and W-based guanidinato complexes as MOCVD precursors and thermal analysis of the new complexes by TG–DTA analysis will be presented. The MOCVD of TaN, W x N thin film growth using our novel mixed ligand precursors and the film characterization by XRD, SEM, cross-sectional SEM, SNMS and conductivity measurements (four-point probe analysis) is discussed in detail. Ta-guanidinato complexes were also used as a single source precursor for MOCVD of TaN. Nearly stoichiometric cubic TaN films with very less carbon content were obtained with good conductivity values.