  In this paper, we study the semi-classical behavior of distorted plane waves,
on manifolds that are Euclidean near infinity or hyperbolic near infinity, and
of non-positive curvature. Assuming that there is a strip without resonances
below the real axis, we show that distorted plane waves are bounded in
$L^2_{loc}$ independently of $h$, that they admit a unique semiclassical
measure, and we prove bounds on their $L^p_{loc}$ norms.
