GaP heteroepitaxy on Si(001): Correlation of Si-surface structure, GaP growth conditions, and Si-III/V interface structure J. Appl. Phys. 111, 083534 (2012); 10.1063/1.4706573Thickness inhomogeneities and growth mechanisms of GaP heteroepitaxy by organometallic chemical vapor deposition J.The authors report real-time spectroscopic-polarimetric determinations of the initial phase of GaP heteroepitaxy by organometallic chemical vapor deposition on nanoscopically roughened ͑NR͒ ͑001͒Si substrates, where polarimetry measurements are also used to quantify roughness. The authors compare the results with analogous data for GaP homoepitaxy and the initial phase of GaP heteroepitaxy on ͑001͒GaAs. The large density of nucleation sites on NRSi significantly improves film continuity relative to nonroughened vicinal ͑001͒Si substrates, but conditions that are typically used to grow GaP on ͑001͒III-V surfaces generate metallic Ga, indicating that NRSi is more efficient at decomposing trimethylgallium than either GaP or GaAs.