A method includes forming a first conductive feature, depositing a passivation layer on a sidewall and a top surface of the first conductive feature, etching the passivation layer to reveal the first conductive feature, and recessing a first top surface of the passivation layer to form a step. The step comprises a second top surface of the passivation layer. The method further includes forming a planarization layer on the passivation layer, and forming a second conductive feature extending into the passivation layer to contact the first conductive feature.