This paper reviews the technique of photochemical‐assisted vapor deposition (photo‐CVD), and its applications in silicon IC processing. The photo‐CVD process deposits SiO2 films (PHOTOX™) at temperatures as low as 50°C. The deposition process, the resulting film properties, and the use of PHOTOX SiO2 for lateral isolation among transistors and vertical isolation between two‐level interconnects are discussed. A novel process employing PHOTOX deposition in conjunction with a photoresist liftoff can be used to achieve totally isoplanar isolation. Photo‐CVD can also be extended to produce other dielectrics such as silicon nitride and aluminum oxide.