Abstract: tract: To meet the high stability requirement of impurity concentration for boron phosphorus silicate glass (BPSG) dielectric film standard samples used in the calibration of semiconductor integrated circuit doping element measurement equipment, a process scheme is proposed to deposit different thickness protective layers on the upper surface of the BPSG layer and then anneal. The influence of protective layer thickness on the stability, accuracy of value assignment and measurement model of the standard samples is systematically studied, and the problem of unstable boron and phosphorus impurity concentrations is solved. XPS analysis indicates that annealing led to the diffusion and precipitation of boron and phosphorus elements into the protective layer, and the thickness of the protective layer should be greater than 50 Å. ICP/MS analysis shows that the thickness of the protective layer is not related to the stability of impurity concentration of the standard samples, but is linearly correlated with the measurement results. Based on this, a method for accurately determining the impurity concentration of boron and phosphorus elements in the BPSG dielectric film of the standard samples based on linear compensation is proposed. Further combined with the FT-IR measurement results, the influence of protective layer thickness on measurement accuracy is investigated, and the optimal thickness of the protective layer for the standard samples is determined to be 100 Å. This study provides a feasible solution for the development and value assignment of high-stability BPSG standard samples.