Image sensor and forming method thereof

Embodiments of the present disclosure describe a method for forming a mirror microstructure on a radiation sensing region of an image sensor device. The method includes forming an opening in a front side surface of a substrate; forming a conformal injection layer on the surface of the bottom and the side wall of the opening; growing a first epitaxial layer on the surface of the bottom and the side wall of the opening; a second epitaxial layer is deposited on the first epitaxial layer to fill the opening, wherein the second epitaxial layer forms a radiation sensing region. The method further includes depositing a stack on the exposed surface of the second epitaxial layer, wherein the stack includes alternating pairs of high index material layers and low index material layers. The embodiment of the invention provides an image sensor and a forming method thereof. 本公开的实施例描述了一种用于在图像传感器装置的辐射感测区域上形成镜子微结构的方法。该方法包括在衬底的前侧表面内形成开口；在开口的底部和侧壁表面上形成共形的注入层；在开口的底部和侧壁表面上生长第一外延层；在第一外延层上沉积第二外延层以填充开口，其中第二外延层形成辐射感测区域。该方法还包括在第二外延层的暴