Powder selection for hydrothermally processed sol–gel composite barium strontium titanate capacitors
Bibliographic record
Abstract
Ba0.7Sr0.3TiO3 (BST) capacitors for high frequency circuits have been fabricated at 175 °C on epoxy‐based copper‐clad printed circuit boards, having a glass transition temperature of ∼200 °C by hydrothermal processing of dried BST acetate‐based sol–gel powder slurries. The film thickness was 2–10 μm. BST powders were prepared respectively as ceramic derived powders processed from oxide mixtures fired to 1100 °C, sol–gel derived powders fired to 750 and 1100 °C, and a low temperature solution process dried at 500 °C. The performance of the capacitor was determined by both the dielectric properties of the powder and the interaction between the crystallizing gel and the powder surface. High relative permittivity is obtained for sol–gel derived powders fired to 750 °C, while high voltage tunability is a characteristic of the ceramic derived powders. Low temperature powders are ineffective. The difference is attributed to the nature of the crystalline interface formed between the surface of the powder particles and the hydrothermally crystallized BST formed from the dried gel within the composite. The optimum molar concentration of the hydrothermal solution was 0.1 M with a Ba content larger than that of the powder. Capacitor composites having a relative permittivity of up to 300 at 20 MHz were demonstrated.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
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 source (direct Gemma or distilled Codex), 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".