Temperature-Dependent<i>in Situ</i>Studies of Volatile Molecule Trapping in Low-Temperature-Activated Zr Alloy-Based Getters
Bibliographic record
Abstract
The activation process and the gettering mechanisms of Zr–Co-rare earth metal alloy getters were investigated. The evolution of the surface composition prior to and upon exposure to volatile molecules (O 2, N 2, CO 2 ) was monitored in situ using X-ray photoelectron spectroscopy under annealing conditions compatible with low processing temperature regimes. The thermally activated process of surface oxygen diffusion into the bulk was elucidated and found to involve an activation energy of 0.21 ± 0.02 eV in the 200–350 °C temperature range. This activation process was also found to reversibly transform ZrO 2 into Zr(OH) 2 through the interaction with thermally desorbed hydrogen. Carbidic species form upon annealing at 250 °C via the interaction with an adventitious carbon layer on the surface, which results in the decrease in the number of surface sites available for subsequent gettering. In situ studies of the material reactivity with high purity O 2, N 2, and CO 2 were also investigated. O 2 was found to saturate the surface after single exposure, while CO 2 dissociates into CO and O –, where O – is incorporated deeper in the material and CO forms an ad-layer on the surface of the getter. N 2 was found to weakly interact with the partially activated surface and to form ZrN only upon annealing the sample to 350 °C indicating the poor reactivity of the material with N 2 at room temperature. The results display the importance of ridding systems of residual gases, especially N 2, by properly degassing the system prior to sealing to minimize and/or eliminate trapped gases within devices during operation.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".