Interface Constraint Effect and Stress Relaxation in Nano-Sandwiched Thin Film

Micro-particles and nano-wires, small outgrowths were found to appear on upper film surface when metal thin film is confined between two Si3N4 layers deposited by magnetron sputtering and is annealed at an appropriate temperature. The stress evolution during this process is monitored by multi-beam optic stress sensor, and is qualitatively interpreted in terms of elastic and plastic deformation, as well as bulk diffusion. Additionally, the interface constraint effect among different layers is explored. Stress relaxation of nano-sandwiched thin films behaves in different stress modes. As a comparative study, Si3N4/Zn/Si3N4 sandwiches were prepared and studied by the same method. Experimental results show that the pertinent geometry is strongly dependent on material types and stress states of the substrates. Finally, an appropriate mode was suggested to interpret this phenomenon.

Research and Development of the Artemis 14C AMS Facility: Status Report

The Artemis accelerator mass spectrometry (AMS) facility is dedicated to high-precision radiocarbon measurements. It routinely measures over 4500 samples a year for French laboratories. This paper is a status report, showing the measurements of standard, blank, and FIRI intercomparison samples. Since 2008, research and development programs have been established by the Artemis team. During the collaborations with other research laboratories, intercomparisons on archaeological samples were performed and are listed here to show the quality of the Artemis measurements. Three areas of specific research and development are investigated: technical development, beam optic simulations, and specific archaeological studies. The technical developments of the facility are based on the setup of a new bench for water sample preparation and routine microsample preparation and measurement. Beam optic simulations are carried out to control the quality of the measurement related to the tuning of the facility. International collaborations are always in progress. In 2012, the programs include improving the accuracy of reigns for the dynastic Egypt period and the 14C dating of ancient iron.