We have investigated vicinal Si(1 1 0) surfaces with various off-angles using atomic force microscopy and transmission electron microscopy. The vicinal surfaces were tilted from the exact Si(1 1 0) surfaces by 2-8 degrees toward the [1 (1) over bar 0] direction. Peculiar surface structures were observed with a strong dependence on the off-angles, including triangular pyramid-like structures on 2 degrees off surfaces, line structures on 4 degrees and 8 degrees off surfaces and nanometer-height mountain structures on 6 degrees off surfaces. The structures on 2 degrees and 4 degrees off surfaces were based on the stair-like structure composed of Si(1 1 0) terraces and monolayer steps. On the other hand, 6 degrees and 8 degrees off surfaces could be understood in terms of Si(1 1 0) terraces and bunched steps. (C) 2012 Elsevier B. V. All rights reserved.