Abstract:
The present invention relates to a photodiode of an image sensor using a three-dimensional multi-layer substrate, and more particularly, to a method of implementing a buried type photodiode and a structure thereof, and a trench contact method for connecting a photodiode in a multi-layer substrate and a transistor for signal detection.
Abstract:
The present invention relates to semiconductor process technology. That is, the present invention relates to the fabrication of a three-dimensional semiconductor structure and a semiconductor device and an optical image sensor having the device as an active pixel. According to the present invention, a buffer oxide film, a nitride film, and an ONO dielectric layer are formed on a handle wafer. A semiconductor layer and an oxide film are formed on a donor wafer. The donor wafer is turned over through a layer transfer process and is then bonded to a top surface of the handle wafer. Silicon of the donor wafer is then removed. In the same manner, blue, green, and red diode layers, and a transistor layer are sequentially formed. A metal layer is formed on the transistor layer. Inter-elements contact and pixel separation processes are performed and a support layer is bonded. The whole device is turned over and the nitride film is etched using an etch-stop layer, thus removing the handle wafer. After the elements are separated, packaging is performed to complete the device. Therefore, a back illuminated image sensor of a multi-layer structure can be provided.
Abstract:
The present invention relates to a semiconductor device, and more particularly, a semiconductor device having a multi-level photodiode structure to maximize quantum efficiency for each wavelength. The semiconductor device includes a plurality of photodiode layers formed in a multi-level structure, an all-reflection layer formed under the photodiode layers, and a transistor layer formed under the all-reflection layer. Internal filter stacks respectively corresponding to wavelengths can be formed on the photodiode layers. Otherwise, external color filters such as anti-reflection coating layers or IR filters, which respectively correspond to wavelengths, can be added to the semiconductor device.