Semiconductor device may include a landing pad and a lower electrode that is on and is connected to the landing pad and includes an outer portion and an inner portion inside the outer portion. The outer portion includes first and second regions. The semiconductor devices may also include a dielectric film on the first region of the outer portion on the lower electrode and an upper electrode on the dielectric film. The first region of the outer portion of the lower electrode may include a silicon (Si) dopant, the dielectric film does not extend along the second region of the outer portion. A concentration of the silicon dopant in the first region of the outer portion is different from a concentration of the silicon dopant in the second region of the outer portion and is higher than a concentration of the silicon dopant in the inner portion.