The effect of temperature on the epitaxial quality of bilayers of iridium silicide and SiGe deposited on Si(100) in ultrahigh vacuum

Abstract

Ir-silicide/SiGe layers were co-deposited on a p-Si(100) substrate at high temperatures. Reflection high energy electron diffraction, transmission electron microscope, and grazing angle incidence X-ray diffraction have been used in characterizing the co-deposited layers. Heteroepitaxial Ir-silicide/SiGe layers on top of p-Si(100) have been achieved at a substrate temperature of 450°C. The Ir-silicide layer was determined to be Ir 3Si 4 with four types of epitaxial modes. The three principal axes ( a = 18.551 A ̊ , b = 3.840 A ̊ , and c = 5.713 A ̊ ) were found to be strained, slightly different from those in the bulk Ir 3Si 4 ( a = 18.870 A ̊ , b = 3.679 A ̊ , and c = 5.774 A ̊ ). The Ir-silicide/SiGe layers co-deposited at 550 and 525°C showed dual phases and polycrystalline structures. corresponding to three-dimensional island growth.