Solid state imaging device and manufacturing method thereof

Abstract

The invention provides a solid state imaging device capable of accurately reading electric charge accumulated in a photodiode and a manufacturing method thereof. The solid state imaging device provided by an embodiment comprises a semiconductor substrate, a photodiode which is disposed in the semiconductor substrate and is provided with a first conductive type semiconductor layer, a shielding layer which is disposed on the above photodiode and contains a second conductive type semiconductor layer in the upper portion or the whole of the shielding layer; and a transmission transistor which is disposed on the semiconductor substrate and transmits the electric charge accumulated in the photodiode to a floating diffusion layer. The top surface of the shielding layer is higher than that of the semiconductor substrate.

Description

[0001] This application enjoys the priority of Japanese Patent Application No. 2011-253710 filed on November 21, 2011, and the entire content of the Japanese Patent Application is cited in this application. technical field [0002] Embodiments of the present invention relate to a solid-state imaging device and a method of manufacturing the same. Background technique [0003] In recent years, the demand for imaging parts of mobile phones has increased rapidly. In addition, there is a strong demand for higher image quality and higher performance of CMOS sensors, especially pixel miniaturization in order to meet the demand for larger pixels (pixels). Along with this demand for higher image quality, it is required to further reduce dark noise generated in pixels and / or defective pixels recognized as white spots on the screen called white spots. This is due to the occurrence of dark current and / or leakage current due to an interface level formed at the interface of the silicon s...

AI Technical Summary

Problems solved by technology

Thus, an increase in threshold voltage and / or a decrease in on-current are caused, resulting in deterioration of transistor characteristics as

As a result, even if the transfer transistor is turned on, the charge accumulated in the charge accumulation diffusion layer of the photodiode is difficult to transfer to the floating diffusion layer, so the performance as a photosensor deteriorates.

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