The incorporation and distribution of nitrogen in ammonia nitrided thermal polyoxide (NPOX) dielectric films and their degradation durability to reduced pressure, dichlorosilane (SiH2Cl2)-HCl-H-2 ambient during epitaxial lateral overgrowth (ELO) indicated that the surface nitrogen concentration had no effect. However, a bulk nitrogen concentration as low as 8 at. % significantly reduced the formation of ELO ambient induced pinholes in 250 Angstrom polyoxide films. After 40 min of ELO ambient stress the electrical yield was raised from 0%, for the control polyoxide dielectric capacitors, to 84% for NPOX dielectric capacitors. Analyses of the failed devices suggest that active pinhole generation still exists, however, the bulk nitrogen concentration dramatically reduces the frequency and rate at which these dielectric defects are produced.