Simulation results are presented for design of high-density imager in the form of 3-phase BCCD with three layers of polysilicon gates. To assure a high charge transfer efficiency we have considered a process with a dual gate dielectric having 350Å Si0₂ layer covered with 650Å Si₃N₄ layer. 1-D process and device simulations were done using SUPREM III and PISCES IIB was used for 2-D device simulations.