| 摘要 |
PURPOSE: A unit pixel of a CMOS(Complimentary Metal-Oxide-Silicon) image sensor having an improved reset transistor is provided to change a structure of a reset transistor to improve operations of resetting a PD(Photo Diode) and an FD(Floating Diffusion) region, thereby enhancing dark current characteristics and optical sensitivity and reducing distortion of image data. CONSTITUTION: A PD(20) receives light to generate photogenerated charges. A transfer transistor(21) of which a drain terminal is connected to the PD(20) and a source terminal is connected to a FD region(22) transfers the photogenerated charges of the PD(20) to the FD region(22). The FD region(22) receives the photogenerated charges from the PD(20) and is connected to a gate terminal of a drive transistor(25). A first reset transistor(23) connected between the PD(20) and a power voltage terminal resets the PD(20). A second reset transistor(24) connected between the FD region(22) and the power voltage terminal resets the FD region(22). The drive transistor(25) of which the gate terminal is connected to the FD region(22) is connected between the power voltage terminal and a select transistor(26). The select transistor(26) connected between the drive transistor(25) and a load resistance(27) performs addressing for switching. The load resistance(27) of which one end is connected to the select transistor(26) is provided. |
