X-ray diffraction (XRD), transmission electron microscopy (TEM), and transmission electron diffraction (TED) were used to measure the texture of undoped poly-Si1-xGex thin films with x = 0, 0.018, 0.13, and 0.31. The films were grown by chemical vapor deposition onto oxidized Si wafers covered with a thin poly-Si seed layer, which was deposited using SiH4 to assist nucleation. SiH2Cl2 was used to deposit the poly-Si reference sample, and SiH2Cl2 mixed with GeH4 was used for Si1-2Gex. To span a wide range of Ge content, the deposition temperature was lowered hom 800 degreesC (x=0) to 600 degreesC (x=0.31) as the Ge fraction increased. All films, independent of Ge content (0 less than or equal tox less than or equal to0.31), showed similar XRD spectra. The spectra exhibited a strong {110} fiber texture, with the intensity for differently oriented grains decreasing in the sequence {110}, {311}, and {111} for all films, even though grains in the seed layer appeared to be randomly oriented. Wedge-shaped specimens analyzed by TED showed that (110) texture was already present at the bottom (film/seed-layer interface) of all the films investigated and increased toward the top (film/air interface). Cross-section TEM images showed that all films exhibited a columnar structure and contained numerous V-shaped grains. Plan-view TEM showed the presence of numerous microtwins in all films. The results suggest that, under our experimental conditions, similar mechanisms dominate the development of texture in Si1-xGex and in poly-Si.