Atomic Layer Deposition of TiN Films by Alternate Supply of Tetrakis(ethylmethylamino)-Titanium and Ammonia

• Published in: Japanese Journal of Applied Physics Vol. 37; no. 9R; p. 4999
• Main Authors: Min, Jae-Sik, Son, Young-Woong, Kang, Won-Gu, Chun, Soung-Soon, Kang, Sang-Won
• Format: Journal Article
• Language: English
• Published: 01.09.1998
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/JJAP.37.4999

Atomic layer deposition (ALD) of amorphous TiN films on SiO 2 between 170°C and 210°C has been investigated by alternate supply of reactant sources, Ti[N(C 2 H 5 CH 3 ) 2 ] 4 [tetrakis(ethylmethylamino)titanium:TEMAT] and NH 3 . Reactant sources were injected into the reactor in the following order:TEMAT vapor pulse, Ar gas pulse, NH 3 gas pulse and Ar gas pulse. Film thickness per cycle was saturated at around 1.6 monolayers (ML) per cycle with sufficient pulse times of reactant sources at 200°C. The results suggest that film thickness per cycle could exceed 1 ML/cycle in ALD, and are explained by the rechemisorption mechanism of the reactant sources. An ideal linear relationship between number of cycles and film thickness is confirmed. As a result of surface limited reactions of ALD, step coverage was excellent. Particles caused by the gas phase reactions between TEMAT and NH 3 were almost absent because TEMAT was segregated from NH 3 by the Ar pulse. In spite of relatively low substrate temperature, carbon impurity was incorporated below 4 at.%.