A device structure according to the present disclosure includes a passivation layer, a first conductor plate layer disposed on the passivation layer, a second conductor plate layer disposed over the first conductor layer, a third conductor plate layer disposed over the second conductor layer, and a fourth conductor plate layer disposed over the third conductor layer. The second conductor plate layer encloses the first conductor plate layer and the fourth conductor plate layer encloses the third conductor plate layer. The device structure, when used in a back-end-of-line passive device, reduces leakage and breakdown due to corner discharge effect.