The fraction of close-in super Earths (r < 0.2 AU) for a range of stellar masses (x-axis) and disc sizes (colours). In all cases, no super-Earths are formed around stars with a mass of 0.1 M_⊙. When only considering discs heated by irradiation (left), the fraction of super-Earths increases with increasing stellar mass regardless of disc size. In the viscously heated case (right), the fraction of super-Earths reaches a maximum at 0.5 M_⊙ and then declines slightly for large discs (90 AU or larger). For smaller discs (30 and 60 AU), the super-Earth fraction peaks at 1 M_⊙, while for larger discs it peaks at 0.5 M_⊙.