  Primordial black holes (PBH) have been shown to arise from high peaks in the
matter power spectra of multi-field models of inflation. Here we show, with a
simple toy model, that it is also possible to generate a peak in the curvature
power spectrum of single-field inflation. We assume that the effective dynamics
of the inflaton field presents a near-inflection point which slows down the
field right before the end of inflation and gives rise to a prominent spike in
the fluctuation power spectrum at scales much smaller than those probed by
Cosmic Microwave Background (CMB) and Large Scale Structure (LSS) observations.
This peak will give rise, upon reentry during the radiation era, to PBH via
gravitational collapse. The mass and abundance of these PBH is such that they
could constitute the totality of the Dark Matter today. We satisfy all CMB and
LSS constraints and predict a very broad range of PBH masses. Some of these PBH
are light enough that they will evaporate before structure formation, leaving
behind a large curvature fluctuation on small scales. This broad mass
distribution of PBH as Dark Matter will be tested in the future by AdvLIGO and
LISA interferometers.
