亚50 nm台阶高度标准物质的可控制备及定值研究

The nano-step height reference materials can deliver accurate and traceable nanometer height characteristic parameters. To investigate the fabrication technique of high-quality sub-50 nm step height reference materials in China, a method based on atomic layer deposition combined with wet etching is proposed. The sub-50 nm step height reference materials with a minimum height of only 5 nm are fabricated through process optimization, which achieves the precise control of the step height in the order of the sub-nanometer. The calibration results are traceable to the national meter-defined wavelength reference, and the extended uncertainty is less than 2.0 nm. Meanwhile, the reference materials has excellent uniformity and stability, and the consistency level of different measurement instruments is quite high. The results show that the nano-step height reference materials can be used for transmission of sub-50 nm height values and comparative measurement between multiple instruments. The prospect of their industrialized production will also provide a perfect metrology guarantee for the semiconductor industry.