A method for minimizing particle generation during deposition of a graded Si.sub.1-xGe.sub.x layer on a semiconductor material includes providing a substrate in an atmosphere including a Si precursor and a Ge precursor, wherein the Ge precursor has a decomposition temperature greater than germane, and depositing the graded Si.sub.1-xGe.sub.x layer having a final Ge content of greater than about 0.15 and a particle density of less than about 0.3 particles/cm.sup.2 on the substrate.