Precise measurement of ultrathin film thickness via a neutron capture reaction

Abstract

Accurate measurement of ultrathin film thickness is of significant importance in both scientific research and industrial applications. In this study, a neutron capture reaction was successfully employed to measure the thickness of ultrathin Cu films (∼nm) as well as applied to determine the thickness of materials in the semiconductor industry, specifically Si₃N₄ films. The method was demonstrated to be non-destructive and applicable to several different films. Finally, a methodology is proposed to guide the experimental design for thickness measurement. This suggests that the nondestructive method provides a novel approach for measuring thin film thicknesses ranging from the nanoscale to the microscale.