A manufacturing method of an electronic device includes applying a direct voltage having a first polarity to a capacitor that has an insulating layer including nitrogen and silicon as a capacitor dielectric layer, testing the capacitor to which the direct voltage having the first polarity is applied and determining a nondefective capacitor and a defective capacitor, and applying a direct voltage having a second polarity to the nondefective capacitor. The second polarity is opposite to the first polarity.