Identifying and characterizing epitaxial graphene domains on partially graphitized SiC(0001) surfaces using scanning probe microscopy

Scanning tunneling microscopy (STM), atomic force microscopy (AFM), lateral force microscopy (LFM), and conductive AFM (cAFM) are employed to characterize epitaxial graphene on SiC(0001). Of particular interest are substrates that possess single-layer and bilayer graphene domains, which form during thermal decomposition of silicon from SiC(0001). Since these samples are often partially graphitized, characterization techniques are needed that can distinguish domains of epitaxial graphene from the adjacent (6 root 3x6 root 3)R30 degrees reconstructed SiC(0001) surface. The relative merits of STM, AFM, LFM, and cAFM for this purpose are outlined, thus providing nanometer-scale strategies for identifying and characterizing epitaxial graphene.