We use experiments to study the dynamics of the healing of a blister, a localized
bump in a thin elastic layer that is adhered to a soft substrate everywhere except at the bump.
We create a blister by gently placing a glass cover slip on a PDMS substrate. The pressure jump
across the elastic layer drives fluid flow through micro-channels that form at the interface between
the layer and the substrate; these channels coalesce at discrete locations as the blister heals and
eventually disappear at a lower critical radius. The spacing of the channel follows a simple scaling
law that can be theoretically justified, and the kinetics of healing is rate limited by fluid flow, but
with a non-trivial dependence on the substrate thickness that likely arises due to channelization.
Our study is relevant to a variety of soft adhesion scenarios.