Image sensor devices, design methods thereof, and manufacturing methods thereof are disclosed. In some embodiments, a design method for an image sensor device includes providing an initial design for an image sensor device. The initial design includes a pixel array region and a through-via region disposed proximate the pixel array region. The initial design has a first length between the pixel array region and the through-via region. The initial design has a second length that is a width of the through-via region. The design method includes analyzing a ratio of the second length and the first length, and modifying the initial design to achieve an optimal ratio of the second length and the first length.