Reconstructions and phase transition of clean Ge(110)

The structure of the clean Ge(110) surface is characterized between room temperature and the Ge melting temperature using scanning tunneling microscopy (STM) and low energy electron diffraction (LEED) and microscopy (LEEM). Rapid cooling from high temperature (~ 800 °C) to room temperature yielded a surface composed of the c(8 × 10) reconstruction, {17 15 1} facets, and a previously unreported (8 × 2) reconstruction. Heating from room temperature to above 430 °C extinguishes some, but not all, high-order LEED spots, indicating the presence of ordering up to at least 650 °C. LEED observations of the phase transition between the c(8 × 10) and a disordered phase differ from earlier work but are consistent with previously published STM data.