  When the charged Higgs boson is too heavy to be produced in pairs, the
predominant production mechanism at Linear Colliders is via the single charged
Higgs boson production processes, such as $e^-e^+ \to b \bar c H^+, \tau \bar
\nu H^+$ and $\gamma\gamma \to b \bar c H^+, \tau \bar \nu H^+$. We show that
the yield of a heavy charged Higgs boson at a $\gamma\gamma$ collider is
typically one or two orders of magnitude larger than that at an $e^-e^+$
collider. Furthermore, a polarized $\gamma\gamma$ collider can determine the
chirality of the Yukawa couplings of fermions with charged Higgs boson via
single charged Higgs boson production, and thus discriminate models of new
physics.
