Image Sensor Stacked Capacitor Charge Storage

The capacitor is divided into multiple separate capacitor structures (first capacitor structure, second capacitor structure, third capacitor structure) instead of using a single capacitor. Each capacitor structure has its own electrodes and dielectric layer, allowing distributed charge storage across multiple components. This segmentation increases total charge storage capacity while maintaining manageable complexity through modular design

The patent transitions from a planar capacitor layout to a three-dimensional stacked configuration. Capacitor structures are arranged vertically with different height levels, where the first capacitor structure has a first height, the second capacitor structure has a second height, and the third capacitor structure has a third height. This vertical stacking in the third dimension increases storage capacity without expanding the lateral footprint, effectively resolving the contradiction between storage capacity and device complexity

The patent utilizes vertical stacking in the third dimension to increase capacitor volume and charge storage capacity. By arranging capacitor structures at different heights and stacking them vertically, the design achieves larger total capacitor volume without proportionally increasing the lateral pixel area occupation. This allows sufficient charge storage capacity while preserving more photoelectric conversion area in the horizontal plane

The capacitor structures are nested vertically within the pixel structure, with the first capacitor structure positioned at a first height level, the second capacitor structure at a second height level, and the third capacitor structure at a third height level. This nested vertical arrangement allows multiple capacitor volumes to occupy overlapping lateral spaces at different vertical levels, maximizing charge storage capacity within the constrained pixel area