An improved semiconductor thin film thickness measurement method based on full-spectrum fitting technology

With the advancement of semiconductor technology, thin films play an irreplaceable role in communications and integrated circuits as their thickness and optical parameters critically impact the performance of integrated circuits, displays, optoelectronic devices, and solar cells. Currently, full-spectrum fitting is commonly used to determine semiconductor thin film thickness. Based on this technique, this paper proposes an improved method for measuring semiconductor thin film thickness using full-spectrum fitting. The method introduces a scaling factor in the reflection spectrum fitting to enhance the reflectance curve fitting accuracy. In addition, it combines the simulated annealing algorithm with the quasi-Newton method to determine film thickness from the reflection spectrum. Experimental results show that compared with existing full-spectrum fitting algorithms, this method improves computational efficiency by 50%, expands the initial value range by 39%, and reduces error by ∼20%. This approach has significant practical value for studying and measuring the optical properties and thickness of semiconductor thin films.