From March 25 to March 31, the AQSIQ organized a project acceptance meeting at China Institute of Metrology (hereinafter referred to as "China Institute of Metrology"), respectively, on the subject of the National Science and Technology Support Program "Research on Metrological Standards and Reference Materials for Micro / Under the 9 sub-topics for acceptance. On the 25th, undertaken by the Chinese Academy of Metrology, the subject of "Research on key technologies in the establishment and traceability of micrograms quality and micro / nano-force standards" collaborated by Tianjin University was evaluated by experts and passed the acceptance test.
At the task acceptance meeting, panelists from 11 units including Beijing Great Wall Metrology and Measurement Technology Institute, China Information and Communication Research Institute, Tsinghua University and Nankai University listened to the task force report and reviewed the acceptance materials. After questioning and discussing, It is considered that the subject has successfully developed the mass measurement standard and automatic measurement system of 500μg, 200μg, 100μg and 50μg, and the standard device of micro-nano force in the range of force value (10-8 ~ 10-4) N, Nali value of the standard measurement capabilities blank, the construction of micrograms and micro-nano-force traceability system.
For international trade, quality measurement plays a decisive role; while the need to explore the micro-world in fields such as new materials, micro / nano processing, and biomedicine challenges the accuracy and limits of quality and force measurement. According to the project leader, deputy director of China Academy of Metrology Hu Gang introduced in the field of biomedicine, preparation of high performance liquid chromatography solution, the quality of some of the standards used in milligrams or even micrograms of grams, and for the standard weighing trace The balance needs the microgram quality standard to guarantee its measurement accuracy and reliability. In the field of microelectronics, the constitutive relations between MEMS devices and packaging materials, thermal expansion coefficient, Young's modulus and other mechanical and physical properties also urgently require accurate traceability of micro / nano force values.
In order to reproduce and transmit the micrograms of micronaire and micro-nano-force, and establish the measurement capability that can be traced back to SI units, the China Metrology Institute and Tianjin University jointly carried out a study on metrology standards of micrograms and micronaids. The research group lasted four years and successfully developed two sets of microgram quality standards, one set of microgrammetric quality measurement systems and two sets of micro and nano-force standard equipment. The overall technical indicators and performance have reached the international advanced level, Quality, electrical and length benchmarking traceability.
Among them, the established microgrammetric metrological standard (first) has an extended measurement uncertainty of more than 0.094μg (k = 2) at the 50μg mass point. This is equivalent to a thousandth of a second of a drop of water (0.05g) reproducibility, with an expansion uncertainty of no more than one-fifth of this drop of water. The micro-Nano standard device with mass method has a resolution of 1nN and a relative standard uncertainty of 0.4% in the range of (1 ~ 10) μN. "It is both sensitive and accurate," Hu Gang explained. "This places a high demand on the measurement method and must analyze and reduce the effects of deformation and environmental factors on the measurement results." He said the group adopted Adopting self-designed flexible hinge mechanism and differential measurement system scheme not only ensures the high sensitivity of the system but also improves the measurement accuracy.
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