SiW ECAL for future $e^{+}{e}^{-}$ collider

Calorimeters with silicon detectors have many unique features and are proposed for several world-leading experiments. We discuss the tests of the first three 18x18 cm${}^2$ layers segmented into 1024 pixels of the technological prototype of the silicon-tungsten electromagnetic calorimeter for a future $e^{+}{e}^{-}$ collider. The tests have beem performed in November 2015 at CERN SPS beam line.