High tensile stress in a deposited layer such as silicon nitride, may be achieved utilizing one or more techniques, employed alone or in combination. High tensile stress may be achieved by forming a silicon-containing layer on a surface by exposing the surface to a silicon-containing precursor gas in the absence of a plasma, forming silicon nitride by exposing said silicon-containing layer to a nitrogen-containing plasma, and then repeating these steps to increase a thickness of the silicon nitride created thereby. High tensile stress may also be achieved by exposing a surface to a silicon-containing precursor gas in a first nitrogen-containing plasma, treating the material with a second nitrogen-containing plasma, and then repeating these steps to increase a thickness of the silicon nitride formed thereby. In another embodiment, tensile film stress is enhanced by deposition with porogens that are liberated upon subsequent exposure to UV radiation or plasma treatment.