The Ti/c-Si solid state reaction : II. Additional measurements by means of RBS, XPS and AES

In a previous paper [Appl. Surface Sci. 40 (1990) 333], we have reported the results of a spectroscopic ellipsometric study of the c-Si/Ti solid state reaction. For this purpose we have grown and heated thin (≈10nm) Ti films on a clean c-Si substrate. The investigation revealed that already at moderate temperatures a metastable silicide (≈350°C), probably a monosilicide, and disilicide (≈450°C) are formed. These two metastable transition states, denoted by state I and II respectively, and the final disilicide (state III, ≈700°C) are additionally studied by means of a number of quantitative techniques, such as RBS, XPS and AES. The results reveal a Si-enriched monosilicide state I, Si: Ti = 1.2 and a stoichiometric but Si segregated disilicide state II; surface composition approximately TiSi₃. The finally obtained disilicide (III) has recrystallized into probably large, flat islands embedded in a c-Si matrix.