  We have grown (InyGa1-y)1-xMnxAs ferromagnetic semiconductor layers with Mn
composition x up to 0.13 on InP substrates by molecular beam epitaxy. Near the
lattice-matched composition, i.e., y ~ 0.53, the Curie temperature increases
linearly with the ferromagnetically effective Mn composition x_eff, following
the empirical equation T_C=1300x_eff. We obtained Curie temperatures above 100
K when x is relatively high (x>0.1; x_eff>0.08) and the hole concentration is
in the order of 10^19 cm^-3.
