Characterization of multilayered Ti/TiN films grown by chemical vapor deposition

Abstract

The resistivity of multilayered Ti/TiN films grown by chemical vapor deposition can be reduced from 240 mu Omega cm (standard sample) to 120 mu Omega cm with NH3 plasma post-treatment for 300 s. Increasing the number of multilayered Ti/TiN mu ms of reduced thickness and a plasma post-treatment technique contributed to reducing the resistivity of TiN films effectively. Smooth multilayered Ti/TiN films were observed by XTEM image. The content of chlorine in the multilayered Ti/TiN film was 1.6 at.%. Therefore, corrosion in the subsequent Al film should be minimized. SIMS depth profiles of the multilayered Ti/TiN sample showed that Ti atom distribution is fairly uniform. The result is in agreement with the observation of XTEM and the measurement of AES depth profiles. The resistivity of multlayered Ti/TiN films can be further reduced to 75 mu Omega cm with an in situ NH3 plasma post-treatment (500 W) for 300 s followed by RTA at 900 degrees C for 60 s. Therefore, low resistivity (<100 mu Omega cm) and low Cl concentration (<2 at.%) CVD TiN films can be achieved by a combination of forming a multilayered Ti/TiN structure, and using NH3 plasma post-treatment and RTA. (C) 1998 Elsevier Science S.A. All rights reserved.