RED/GREEN PIXEL WITH SIMULATION EXPOSURE AND IMPROVED MIT

摘要

PPROBLEM TO BE SOLVED: To provide a method for separating red and green input signals, without using a color filter, and attaining an improved modulation transfer function and resolution. PSOLUTION: A single pixel includes a deep N well 18 formed in a P-type epitaxial substrate 10. A plurality of P wells 20 used as sensor nodes are formed in the deep N well. A depth 32 of the deep N well is almost equal to a depth of hole-electron pair generated in silicon by a red light. A depth 30 of the P wells is almost equal to the depth of the hole-electron pair generated in silicon by a green light. A red/green signal is decided in respective P wells, by insulating the P wells from the deep N well and by deciding electric potentials between respective P wells and the deep N well, after a charge accumulation cycle. A green signal is decided by suppressing a red signal during a charge accumulation period. A red signal is decided by subtracting the green signal from the red/green signal. PCOPYRIGHT: (C)2005,JPO&NCIPI