| 摘要 |
A separation type unit pixel of an image sensor, which can handle light that incidents onto a photodiode at various angles, and provides a zoom function in a mini camera module by securing an incident angle margin, and a manufacturing method thereof are provided. The separation type unit pixel having a 3D structure for an image sensor, composed of a plurality of transistors, includes: a first wafer which includes a photodiode, a transfer transistor, a node of a floating diffusion area functioning as static electricity for converting electric charge into a voltage, and a pad connecting the floating diffusion area and the transfer transistor to an external circuit, respectively; a second wafer which includes the rest of the circuit elements constituting a pixel (i.e., a reset transistor, a source-follower transistor, and a blocking switch transistor), a read-out circuit, a vertical/horizontal decoder, a correlated double sampling (CDS) circuit which involves in a sensor operation and an image quality, an analog circuit, an analog-digital converter (ADC), a digital circuit, and a pad connecting each pixel; and a connecting means which connects the pad of the first wafer and the pad of the second wafer. Accordingly, by forming an area for a photodiode and an area for a pixel almost the same, an image sensor can be manufactured to have a good sensitivity, without having to use a micro lens. In addition, by disposing the photodiode at the top layer, an incident angle margin of incident light can be secured, which has to be basically provided by the sensor for its auto focusing function or zoom function. |
