  In this contribution we describe the second run of RSD (Resistive AC-Coupled
Silicon Detectors) designed at INFN Torino and produced by Fondazione Bruno
Kessler (FBK), Trento. RSD are n-in-p detectors intended for 4D particle
tracking based on the LGAD technology that get rid of any segmentation implant
in order to achieve the 100% fill-factor. They are characterized by three
key-elements, (i) a continuous gain implant, (ii) a resistive n-cathode and
(iii) a dielectric coupling layer deposited on top, guaranteeing a good spatial
reconstruction of the hit position while benefiting from the good timing
properties of LGADs. We will start from the very promising results of our RSD1
batch in terms of tracking performances and then we will move to the
description of the design of the RSD2 run. In particular, the principles
driving the sensor design and the specific AC-electrode layout adopted to
optimize the signal confinement will be addressed.
