We successfully confirmed unique atomic structures in a trench around an InAs quantum dot (QD) at 300 degrees C. The trench structure was consisted by various atomic steps which included 4 x structures (InAs (4 x 2) and/or GaAs (4 x 6)) at an upper terrace edge next to a step. As distant from the upper terrace edge, frequency of 4 x structures decreased and gradually converged to 2 x structures (InAs (2 x 4), InAs (2 x 3), and GaAs (2 x 4)). (c) 2013 Elsevier B.V. All rights reserved.