Characteristics of ALD HfSiO/sub x/ using new Si precursors for gate dielectric applications

We have successfully developed a process for ALD HfSiO/sub x/ that can provide excellent compositional control by using new Si precursors, Si/sub 2/Cl/sub 6/ (HCDS) and SiH[(CH/sub 3/)/sub 2/]/sub 3/ (tDMAS). In addition, comparisons of electrical properties of HfSiO/sub x/ using two Si precursors have been performed. CMOSFET with HfSiO/sub x/ using HCDS results in better reliability characteristics than tDMAS. Superior electron and hole mobility (100% and 90% of universal curve at 0.8MV/cm) are also achieved with HCDS. Consequently, HCDS has the potential to be used as a Si precursor for ALD HfSiO/sub x/.