IMAGE SENSOR AND METHOD OF FORMING IMAGE SENSOR

The invention relates to an image sensor having an image sensing element surrounded by a BDTI structure and a related forming method. In some embodiments, a first image sensing element and a second image sensing element are arranged adjacent to each other within an image sensing die. A pixel dielectric stack is disposed along a backside of the image sensing die overlying the image sensing element. The pixel dielectric stack includes a first high-k dielectric layer and a second high-k dielectric layer. The BDTI structure is disposed between the first image sensing element and the second image sensing element and extends from a backside of the image sensor die to a location within the image sensor die. The BDTI structure includes a trench fill layer surrounded by an isolation dielectric stack. The pixel dielectric stack has a composition different from a composition of the isolation dielectric stack. 本发明涉及具有由BDTI结构围绕的图像感测元件的图像传感器以及相关的形成方法。在一些实施例中，第一图像感测元件和第二图像感测元件在图像感测管芯内彼此相邻布置。像素介电堆叠件沿图像感测管芯的位于图像感测元件上面的背面设置。像素