The present invention is a novel termination of silicon dioxide films for use in a single wafer cleaning tool. According to the present invention a silicon dioxide film is formed on a silicon substrate and the film is then terminated with ammonium oxide (—O—NH4). In an embodiment of the present invention the film is terminated by dispensing a mixture containing ammonium oxide onto the film. The present invention also provides a method of forming a gate insulator as well as a gate insulator device.