LAYER-BY-LAYER GROWTH OF BI2SR2CAN-1CUNOX FILMS WITH N-GREATER-THAN-OR-EQUAL-TO-3 BY MOLECULAR-BEAM EPITAXY

Thin films of Bi2Sr2Can-1CunOx were grown using a layer-by-layer molecular beam epitaxy technique. The results demonstrate that nearly single-phase highly metastable films with n=4 to 11 can be synthesized both on SrTiO3 and MgO substrates and their physical properties studied. X-ray diffraction data of the films with n=8, 9, 10 and 11 are presented. The observed Laue oscillations indicate that the films exhibit high crystal quality and nearly perfect surfaces and interfaces. Resistivity measurements show semimetal-semiconductor transitions to occur at temperatures below 100 K, a result of insufficient doping by holes in the CuO2 planes as n increases.