Abstract
We report on the discovery of Si(100)-(2 × 1)→(2 × n)→c(4 × 4) structural phase transitions. Annealing the Si(100)-(2 × 1) surface between 590 and 700°C for some hours causes dimer vacancies to increase and nucleate into chains, ultimately forming the (2 × n) structure. After further annealing, c(4 × 4) areas appear, grow, and finally cover the entire surface. Experimental results raise the possibility not only that c(4 × 4) is a stable low-temperature structure of Si(100). but that (2 × 1) is a high-temperature phase stabilized at room temperature owing to its kinetic limitations. © 1998 Elsevier Science B.V.