  We report an extensive experimental study of a detachment front dynamics
instability, appearing at microscopic scales during the peeling of adhesive
tapes. The amplitude of this instability scales with its period as
$A_{\text{mss}} \propto T_{\text{mss}}^{1/3}$, with a pre-factor evolving
slightly with the peel angle $\theta$, and increasing systematically with the
bending modulus $B$ of the tape backing. Establishing a local energy budget of
the detachment process during one period of this micro-instability, our
theoretical model shows that the elastic bending energy stored in the portion
of tape to be peeled is converted into kinetic energy, providing a quantitative
description of the experimental scaling law.
