Pixelplus Co., Ltd.

Dae Sung Min

Jung Soon Shin

Seo Kyu Lee

There is provided an image sensor having micro lenses of which pitches decrease by different ratios according to left side and right side ratios, which are arranged in different ratios according to upper side and right side ratios, and of which pitches in the edge area are equal to a pixel pitch to arrange the micro lenses in a predetermined interval, thereby capable of preventing ambient sensitivity from deteriorating and suppressing crosstalk. There is also provided an image sensor having micro lenses arranged in different ratios according to left side, right side, upper side and lower side ratios, which has photodiodes arranged in a predetermined interval and micro lenses for overlapping upper portions of the photodiodes to focus light thereon, wherein the micro lenses, in a first area (which is an area from the center area of the photodiodes to before the edge area), are arranged in predetermined shift ratios according to a distance to +X and &#x2212;X directions or/and +Y and &#x2212;Y directions and, in a second area (the edge area), are arranged in a shift ratio equal to a shift ratio of the last pixel of the first area. Accordingly, the smaller pixel size become, the less the photodiodes take their area. Besides, the lower the heights of the micro lenses are, the more the angle of light incident on the photodiodes increases. As a result, it is possible to reduce crosstalk and increase an ambient light.

Image sensor having micro lenses arranged in different ratios according to left side and right side ratios

A CMOS active pixel of increased sensitivity includes a floating diffusion layer, a photo-diode, a reset circuit and an output circuit The floating diffusion layer is of a first dopant type and receives a signal charge. The photo-diode generates the signal charge depending on an energy inputted thereto and transfers the signal charge to the floating diffusion layer. The photo-diode has first and second lower diode dopant layers of the first dopant type and an upper diode dopant layer of a second dopant type. The polarity of the second dopant type is opposite to that of the first dopant type. The first and second lower diode dopant layers are formed to contact a lower portion of the upper diode dopant layer. The upper diode dopant layer and the first lower diode dopant layer are formed to contact the floating diffusion layer. The second lower diode dopant layer is formed to contact the first lower diode dopant layer. The reset circuit controls a voltage level of the floating diffusion layer to a reset voltage level in response to a control signal. A doping concentration of the first lower diode dopant layer is less than that of the floating diffusion layer. A doping concentration of the second lower diode dopant layer is less than that of the first lower diode dopant layer.

Growing community of inventors

Gyeonggi-do, South Korea

Dae Sung Min