STM studies of C60 on a Si(1 1 1):B surface phase

In this study, the growth of fullerene C60 on Si(1 1 1) surfaces was investigated. Due to the high density of dangling bonds on the Si(1 1 1)–7×7 surface and the resulting low-surface mobility of C60, neither the growth of monocrystalline layers of C60 nor a reconstruction of C60 is possible on this surface. Furthermore, during the growth of fullerenes stress is induced, which results in the formation of islands. The first layer of fullerenes passivates the 7×7 reconstructed surface and enables closely packed reconstructions to be formed on these fullerene islands. However, the islands are observed to be instable during thermal treatment and overgrowth. The passivation of the Si surface and the so-increased surface mobility of fullerenes is found to be the sole reason for a reconstruction of fullerenes. Therefore, the passivation of Si(1 1 1) by a boron surface phase was utilized to induce a closely packed reconstruction of fullerenes already in the first monolayer. This possibility of growing monocrystalline layers of fullerenes opens new possibilities for semiconductor devices.