Effect of H2O chemisorption on passivation of Ge(100) surface studied by scanning tunneling microscopy

►H2O chemisorption at high coverage was obtained on Ge(100) with a saturation H2O dose at 300 K. ►Surface states due to dangling bonds were removed on H2O sites by ―OH and ―H termination. ►Annealing a H2O dosed Ge surface decreased coverage of H2O due to desorption of H2 and H2O. ►H2O chemisorption at room temperature can be an ideal passivation of Ge(100) surface.