Germanium-silicon alloys can be prepared on crystalline silicon (111) substrates and have been observed to have 5×5 surface reconstructions. We present tunneling images of this surface which show that is has strong similarities to the Si(111)7×7 reconstruction. A model related to that proposed by Takayanagi, Ytaniahiro, and Kobayashi accounts for the general features of the observed reconstruction. In addition the surface is observed to have periodic vertical modulations which indicate an ordered Ge-Si surface alloy.
- Received 31 July 1985
- Published in the issue dated 15 December 1985
© 1985 The American Physical Society