Long term stability of silicon roughness standards

• Published in: Precision engineering 2017-04, Vol.48, p.352-356
• Main Authors: Baršić, Gorana, Katić, Marko, Šimunović, Vedran
• Format: Article
• Language: English
• Subjects: Long term stability; Silicon roughness standards
• ISSN: 0141-6359; 1873-2372
• DOI: 10.1016/j.precisioneng.2016.12.010

•Stability of metrological characteristics on roughness standards after 29 years of use has been analysed.•Analysis was based on roughness parameters from calibration certificates provided by several NMIs for two Croatian primary roughness standards.•Results of the Birge ratio test showed a good statistical consistency within the declared levels of measurement uncertainties.•Estimated standard deviations for measured roughness parameters indicate that uniformity of surfaces hasn’t been altered. In 1986 the roughness reference standards made of silicon were produced at the Laboratory for Precise Measurements of Length (LFSB), which is now a part of Croatian Metrology Institute (HMI) designated as HMI/FSB-LPMD. At that time, roughness standards were commonly made either from steel or glass. After 3 decades of use it was decided to conduct a research of metrological features on two silicon roughness standards which were continuously used as primary standards for roughness in Croatia. The analysis is based on measurement results of roughness parameters (Ra, Rz and RSm) from calibration certificates provided by several national metrology institutes. Statistical consistency is checked with Birge ratio test, and En values are calculated in order to check if significant change of roughness parameters over the years can be determined.