The full-frame CCD image sensor is most suitable for digital still cameras. However, its disadvantages include low light sensitivity due to light absorption in the driving electrodes, a high dark current generated at the depleted Si-SiO
2 interface of the CCD register, and a small charge-handling capability due to the surface pinning mode of operation used to reduce dark current. In this paper, we propose a new CCD register that solves these problems. The cell of the register is an inverted version of the conventional photo-diode with overflow drains. Therefore, the register is suitable for back illumination. The overflow drains, which are isolated from each other with an SiO
2 layer, are used as driving electrodes. We analyze the performance of the register by using a three-dimensional numerical simulator and discuss its applicability to full-frame CCD image sensors. The leakage current between electrodes and between electrodes and channels was reduced to a negligible level by adjusting the barrier height. Also, the dark current generated at the Si-SiO
2 interface successfully flowed into the electrodes and decreased drastically. The transfer inefficiency for 6 × 10
4 signal electrons, which is determined by the anti-blooming function of the cell, was as low as 10
-11 within a 8 ns transfer time for pushing a pulse with a 4 ns fall time. The new CCD register, which is driven by four-phase drive pulses, handled a charge amount that was several times larger than that of a two-phase CCD using surface pinning mode. We also discuss the relation between the register's design and its performance.
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