1/f noise in an amorphous selenium photo-detect
Bibliographic record
Abstract
In direct-conversion, flat-panel, X-ray image detectors, stabilized amorphous selenium (a-Se) is used as the photoconductive layer because of its reasonably high X-ray absorption, low dark current, and good electronic transport properties. The signal-to-noise ratio of these detectors depends in part on the conductance noise in the selenium layer with the lower noise level providing better image quality. Modeling the performance of these detectors is hampered because noise studies of a-Se have not been reported in the literature perhaps because a-Se is a highly resistive material making such measurements difficult. We report here the first results for the low-frequency conductance noise in layers of a-Se under conditions similar to those found in the detectors. The noise power spectrum fits a 1/f power law with a in the range 0.77 to 1.5. Interpretation of the noise spectra is complicated due to the sample's highly nonlinear I-V relation. However, the noise spectrum depends critically on the type of metal evaporated on the a-Se surface for electrical contacts which indicates that the noise is controlled by the metal-semiconductor interface. Three types of metal electrodes have been measured-platinum, gold, and aluminum
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.000 | 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 | 0.000 | 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".