Methods of preparing a carbon doped oxide (CDO) layers having a low dielectric constant are provided. The methods involve, for instance, providing a substrate to a deposition chamber and exposing it to one or multiple carbon-doped oxide precursors having molecules with at least one carbon-carbon triple bond, or carbon-carbon double bond, or a combination of these groups and depositing the carbon doped oxide dielectric layer under conditions in which the resulting dielectric layer has a dielectric constant of not greater than about 2.7. Methods of preparing a low stress porous low-k dielectric material on a substrate are provided. The methods involve the use of a structure former precursor and/or porogen precursor with one or more organic functional groups. In some cases, the structure former precursor has carbon-carbon double or triple bonds. In other cases, one or both of the structure former precursor and porogen precursor has one or more bulky organic groups. In other cases, the structure former precursor has carbon-carbon double or triple bonds and one or both of the structure former precursor and porogen precursor has one or more bulky organic groups. Once the precursor film is formed, the porogen is removed, leaving a porous low-k dielectric matrix with high mechanical strength. Different types of structure former precursors and porogen precursors are described. The resulting low stress low-k porous film may be used as a low-k dielectric film in integrated circuit manufacturing applications.