An alignment layer for an LCD includes a thin layer of silicon oxide SiOx. The silicon oxide layer horizontally aligns liquid crystals thereon when the value of x is in the range from about 1.0 to about 1.5, but vertically aligns the liquid crystals when the value of x is in a range from about 1.5 to about 2.0. The alignment layer is readily formed on a large area of the substrate through chemical vapor deposition or evaporation deposition. Because the alignment layer is thermally and physically stable, the operational characteristics of the liquid crystal display employing this alignment layer are improved. In addition, the alignment layer has a thickness of about 500 to about 3000 angstroms thereby improving light transmittance of the LCD having the alignment layer.