Abstract
With the discovery of T c values over 100 K, continuously biased hole-doped semiconductive C+y 60 has joined the family of high-temperature superconductors (HTSCs) previously dominated by the ceramic cuprates. The phase diagrams of these two quite different materials are remarkably similar, despite the absence from undoped C+y 60 of magnetic order. This supports percolative models of HTSCs based on strong electron-phonon interactions. These models explain observed fine structure in the C+y 60 phase diagrams, and furthermore suggest novel paths to still higher T c values.