Preferential growth of C54 TiSi 2 by metal vapor vacuum arc ion source implantation and post-annealing

Abstract

Both 〈100〉 and 〈111〉 oriented Si wafers (n-type) were implanted with 45-keV Ti ions to a dose of 4×10 17 ions/cm 2. X-Ray diffraction (XRD) patterns show that there are different initial silicides, such as: C54 TiSi 2, C49 TiSi 2 and Ti 5Si 3. It is interesting that the initial phases are beam current and substrate dependent. When annealing was performed at higher temperature, both the C49 TiSi 2 and Ti 5Si 3 transform into C54 TiSi 2. Moreover, C54 TiSi 2 was grown with various preferential orientations on different substrates in annealing processes. Rutherford backscattering spectrometry (RBS) results show that the Ti atomic profile has little change through annealing. In addition, sheet resistance measurements also reflect that the synthesized disilicide is excellent in electrical conductivity. This suggests that the method has potential for realizing electrical contact in very large-scale integrated (VLSI) circuits.