  We find that the triplet Andreev reflection amplitude at the interface
between a half-metal and an s-wave superconductor in the presence of a domain
wall is significantly enhanced if the half metal is a thin film, rather than an
extended magnet. The enhancement is by a factor $l_{\rm d}/d$, where $l_{\rm
d}$ is the width of the domain wall and $d$ the film thickness. We conclude
that in a lateral geometry, domain walls can be an effective source of the
triplet proximity effect.
