A semiconductor device includes a semiconductor substrate, a first epitaxial feature having a first semiconductor material over the semiconductor substrate, and a second epitaxial feature having a second semiconductor material over the semiconductor substrate. The second semiconductor material being different from the first semiconductor material. The semiconductor device further includes a first silicide layer on the first epitaxial feature, a second silicide layer on the second epitaxial feature, a metal layer on the first silicide layer, a first contact feature over the metal layer, and a second contact feature over the second silicide layer. A first number of layers between the first contact feature and the first epitaxial feature is greater than a second number of layers between the second contact feature and the second epitaxial feature.