Abstract: Embodiments of methods of filling features with molybdenum (Mo) include depositing a first layer of Mo in a feature including an opening and an interior and non-conformally treating the first layer such that regions near the opening preferentially treated over regions in the interior. In some embodiments, a second Mo layer is deposited on the treated first layer. Embodiments of methods of filling features with Mo include controlling Mo precursor flux to transition between conformal and non-conformal fill.