Image sensor device and forming method thereof

Embodiments of the invention provide an image sensor device and a method of forming the same. The method includes forming a mask layer on a back side of a substrate, the substrate including a pixel region having a photodetector, a transistor on or in a front side of the substrate; forming a mask opening in the mask layer by exposing the mask layer to the patterned light, the mask opening including: a mask pixel region of the mask pixel region; and a mask protrusion region extending from the mask pixel region to the mask intersection region; etching the substrate through the mask opening, forming a substrate opening in the substrate; an isolation structure is formed in the substrate opening. 本申请的实施例提供了图像传感器器件及其形成方法。方法包括：在衬底的背侧上形成掩模层，该衬底包括具有光电探测器的像素区域，晶体管位于衬底的前侧之上或之中；通过将掩蔽层暴露于图案化的光而在掩蔽层中形成掩蔽开口，掩模开口包括：掩蔽像素区域的掩蔽像素区域；以及从掩模像素区域向掩模交叉区域延伸的掩模突起区域；通过掩模开口蚀刻衬底，在衬底中形成衬底开口；在衬底开口中形成隔离结构。