  We have constructed all-sky y-maps of the thermal Sunyaev-Zeldovich (tSZ)
effect by applying specifically tailored component separation algorithms to the
30 to 857 GHz frequency channel maps from the Planck satellite survey. These
reconstructed y-maps are delivered as part of the Planck 2015 release. The
y-maps are characterised in terms of noise properties and residual foreground
contamination, mainly thermal dust emission at large angular scales and CIB and
extragalactic point sources at small angular scales. Specific masks are defined
to minimize foreground residuals and systematics. Using these masks we compute
the y-map angular power spectrum and higher order statistics. From these we
conclude that the y-map is dominated by tSZ signal in the multipole range,
20-600. We compare the measured tSZ power spectrum and higher order statistics
to various physically motivated models and discuss the implications of our
results in terms of cluster physics and cosmology.
