Recent deep surveys have resolved great part of the 2-10 keV X-ray background (XRB), showing that it is produced by a mixture of obscured and unobscured Active Galatic Nuclei. The XRB represents the echo of massive black holes through the history of the Universe and, consequently, 0.4<z<1 is the redshift domain in which a major fraction of the black hole mass observed in the local universe is expected to be accreted. On the other hand, the tight relationship between the mass of the local black hole and the mass of the spheroidal component must be the result of the connection between the formation and the evolution of the galaxies with the formation and the growth of the central supermassive black hole. In order to gain insight into this process, in the framework of the Great Observatory Origins Deep Survey (GOODS) we have investigated the properties of the Active Nuclei and their host galaxies. I will present the results of a morphological, photometric and spectroscopic analysis. Based on a bidimensional deconvolution of the ACS-HST images in four bands, performed assuming a three-component model (nucleus+bulge+disk), and using the well-known correlation between central masses and bulge luminosities and a library of QSO template spectra, we obtained an estimation of the distribution of the black hole mass and the Eddington ratio at 0.4<z<1.0. We find that this sample is made up of already formed objects, showing a renewal of low-level activity.