Development of a Highly Granular Silicon-Tungsten ECAL for the ILD

The excellent jet energy resolution required for precise physics measurements at ILC is achievable using a Particle Flow Method and highly granular calorimeters. As it was shown by CALICE international R&D collaboration, the silicon-tungsten imaging electromagnetic calorimeter provides the best granularity, stability and resolution of jet energy measurement. After proving the calorimeter concept with physical prototypes in 2005-2011, an emphasis is now moved to building a technological prototype satisfying challenging requirements. All chosen technologies should be reliable and scalable for a mass production of a future detector. We report on the current status of R&D, in particular, on beam and charge injection tests of the technological prototype and on the tests of ECAL mechanical structure. We also report on our plans to build a realistic prototype detector and test it together with an existing carbon fiber-tungsten mechanical structure. A similar silicon-tungsten calorimeter technology has been recently proposed for the Phase 2 upgrade of CMS end-cap calorimeter and future high energy circular collider projects.