BCMD-An improved photosite structure for high-density image sensors

摘要: The author describes a new improved photosite structure and its use in image sensor that has been developed for applications requiring high-density pixel integration. employs buried-channel MOS transistor with specially designed storage well located under the channel silicon bulk. photogenerated carriers accumulate this modulate threshold. resulting bulk charge modulated device (BCMD) high-sensitivity low-noise high-blooming overload capability, no detectable smear, lag. BMCD photocell integrated into an image-sensing array 8-mm diagonal, 499 lines, 687 pixels each line. individual cells are shaped closely packed hexagons offset by half width between neighbouring lines. together dual-time readout capability gives superior resolution color-sensing applications. high light sensitivity throughout entire visible spectrum is achieved using very thin polysilicon gate. peripheral circuits needed addressing sensing functions on-chip CMOS technology require only TTL driving pulses. further basic steps of fabrication process results testing evaluation completed units. >