Graphene Devices
Graphene, in its 2D state, was discovered a few years ago. There are different approaches to obtaining graphene - epitaxial growth and peeling off layers from highly oriented pyrolitic graphite (HOPG). The latter is less suited for large-scale manufacturing although interesting physical phenomena can be readily studied using such samples. In my research, I rely on epitaxially grown graphene. Efforts are underway to fabricate conventional transistor structures using graphene. The image below shows a side-gated transistor with a sub-30nm channel.
Graphene exhibits ballistic transport, and high current density; this makes it attractive for post-CMOS circuits. However, singl-layer graphene does not exhibit a bandgap; this can be overcome by quantum confinement, application of an external field, or by doping. Manufacturing graphene sheets reliably, and integrating billions of graphene devices into a single chip are challenges that need to be overcome before graphene can replace Silicon.