A thickness model for the stack in the titanium salicide process module

Autor: P.P. Apte, Jiunn-Yann Tsai
Rok vydání: 1995
Předmět:
Zdroj: Thin Solid Films. 270:589-595
ISSN: 0040-6090
Popis: A reliable TiSi 2 TiN stack thickness model is an essential component for modeling the titanium salicide process, and such a model is not well-developed in current process simulators and in the literature. To determine this model, a design of experiments was set up to examine five process variables, namely, as-deposited Ti thickness, reaction temperature, reaction time, As + implanted dose, and the reaction ambient pressure. Weight and sheet resistance measurements were used to evaluate the thickness and efficiency of reaction (%Ti converted to suicide). A good first-order linear model was obtained, with a residual standard deviation (variation of model from data) of ~30 A. The model establishes quantitatively, that the TiSi 2 thickness is proportional to the as-deposited Ti thickness and reaction temperature, inversely proportional to the implanted As + dose, and weakly proportional to the reaction time. Since TiN and TiSi 2 are competing reactions, TiN exhibits inverse functional relationships with the variables, as compared with TiSi 2 . The efficiency of the reaction also has been quantified by the model. The ambient pressure has been found to have no impact on either the TiSi 2 TiN stack thickness, or the reaction efficiency. The model has been validated by cross-sectional transmission electron microscopy, which agrees with the model prediction within experimental error.
Databáze: OpenAIRE