| AVS 64th International Symposium & Exhibition | |
| Vacuum Technology Division | Monday Sessions |
| Session VT-MoA |
| Session: | Material Outgassing, Adsorption/Desorption and XHV |
| Presenter: | JongYeon Lim, Korea Research Institute of Standards and Science, Republic of Korea |
| Authors: | J.Y. Lim, Korea Research Institute of Standards and Science, Republic of Korea K.D. Kim, Infinity Vacuum Technology, Republic of Korea H.S. Oh, Infinity Vacuum Technology, Republic of Korea C.H. Lim, Infinity Vacuum Technology, Republic of Korea Y.D. Joh, Infinity Vacuum Technology, Republic of Korea |
| Correspondent: | Click to Email |
The TDS system, designed for measuring outgassing rate of a diameter of 10 mm sample, with two pumping paths; one is ordinary throughput path with an orifice, the other a UHV path, has been newly developed to measure any molecules on samples with a sophisticated DAQ system.
Two paths are directly connected to the main chamber equipped with devices including a rod-guided halogen heater allowing the sample temperature up to 1200 oC .
The throughput path utilizes the UHV equipment to measure the outgassing rate quantitatively and qualitatively. In the case of quantitative hydrogen measurement, the throughput path does not have enough pumping speed since a small orifice diameter has the conductance limitation.
The experimentally acquired system calibration factor for the throughput method is 16.0, which is defined as the ratio of background outgassing rates with the gate valve closed and open using the throughput method.
In order to verify the measurement reliability a NIST Standard Reference Materials (SRM) was introduced to the TDS system. Most of hydrogen was desorbed during the course of heating process up to 800 oC for 90 minutes. The area under the H2 peak is proportional to the nominal value of 126.8 wt ppm (uncertainty of 2 %). The hydrogen calibration factor of 4.38686E23 was realized. The system claims the hydrogen measurement resolution of 1.3E-6 wt ppm.
In this presentation we briefly introduce the accurate UHV outgassing measurement system for both qualitative and quantitative analyses, which has an 18 % uncertainty of total outgassing rate with Inficon BPG400 HV gauges and a unique self-calibration function.
Acknowledgements: Results are partially attributed to two national projects sponsored by the Korean Ministry of Trade, Industry & Energy, and the KRISS main project (Contract Nos. 10048806, and 170111649).