A Study on the Characteristics of TiN Thin Film Deposited by Atomic Layer Chemical Vapor Depositon Method

Abstract

A TiN film which exhibits a NaCl structure is now used as a diffusion barrier in ULSI device because it shows a very low resistivity, good adhesion characteristics and thermal stability. In this study, we deposited TiN film on Si substrate by using atomic layer chemical vapor deposition system. The TiN film deposited by this method is expected to have excellent physical and electrical properties. In this system, the TiCl4 and NH3 gases as Ti source and an reactant were supplied, separately and Ar purge gas was added between each source and reactant supply to suppress the direct reaction between source and reactant. The process parameters to grow TiN were process temperature, number of cycle to supply the reactant and source gases, source supplying time, and purging time. After growing this TiN film, the physical and electrical properties were measured by XRD, AFM, SEM, AES, TEM, RBS and a four point probe. The crystallinity and the surface and interface were analyzed by XRD, SEM and TEM. The root mean square toughness of TiN surface was measured by AFM and its value was about 15Å. The chemical analysis was done by AES and the Cl content in TiN film was below the detection limit of Auger Electron Spectroscopy shich was below 1%. We will compare these TiN film data with other deposition method, such as PECVD and MOCVD and will discuss the TiN film growing method based on the thermodynamic consideration and atomic size computer modeling