Summary: | 碩士 === 國立成功大學 === 電機工程學系碩士在職專班 === 102 === In this study, the application and investigation of metal organic chemical vapor deposition (MOCVD) TiN films as the diffusion barrier layer of sub W-plug process was explored. MOCVD technique is favorable for the formation of TiN glue layers mainly due to its good step coverage. However, the method of the MOCVD technique has a big disadvantage, huge amount of carbon (C) and oxygen (O) incorporating into the TiN films from TDMAT causes dramatically high in film resistivity. Therefore, the thesis is mainly divided into two parts. Part I is the investigation of the reduction of the resistivity of TiN films. After depositing the TiN films, the different ratio frequency (RF) power is used to treat the TiN films. During treatment process, we can get the TiN films with lower resistance and thermal stability test. The microstructures of the TiN films were analyzed by TEM and SIMS. The results show that the resistivity of the TiN films is obviously lower after the treatment with high power plasma.
Part II is the investigation of galvanic corrosion between W metals and TiNx barriers deposited with various N2 flow rates in W chemical-mechanical-polishing slurry. Electrochemical impedance spectroscopy (EIS), potential dynamic curves, and potential difference measurements were used to characterize the mechanism of galvanic corrosion between the W and the TiNx films deposited with various N2 flow rates. The equivalent circuit, including the charge-transfer resistance and the titanium-oxide resistance associated with tantalum-oxide capacitance, was built to characterize the mechanism of the galvanic corrosion between the W and the TiNx metals. The results show that the N content of the TiNx films influences not only the physical properties of the TiNx films, but also the chemical activity in the WCMP slurries.
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