  It is known that by introducing the Yukawa coupling between the fermion and
the background scalar field, a bulk spin-half fermion can be localized on
general Randall-Sundrum braneworlds generated by a kinklike background scalar.
However, this localization mechanism does not work anymore for Randall-Sundrum
braneworlds generated by a scalar whose configuration is an even function of
the extra dimension. In this paper, we present a new localization mechanism for
spin-half fermions for such a class of braneworld models, in which extra
dimension has the topology $S^1/Z_2$. By two examples, it is shown that the new
localization mechanism produces interesting results. In the first model with
the brane generated by two scalars, the zero mode of the left-handed fermion is
localized on the brane and there is a mass gap between the fermion zero mode
and excited KK modes. In the second model with the brane generated by a dilaton
scalar, the zero mode of the left- or right-chiral fermion can be localized on
the brane and there is no mass gap.
