Investigating the causes of the lower stability of solution-coated versus vacuum-deposited small-molecule organic light emitting devices (Conference Presentation)
Bibliographic record
Abstract
Although the promise of realizing lower cost fabrication by means of solution-based processing techniques, such as spin coating, web coating or inkjet printing, has been one key driver behind the interest in OLEDs for the last two decades, the lower stability of devices made by these techniques has been a long standing issue. With recent advances in developing solution-processable small molecule materials, it is now possible to make OLEDs of the same small molecule materials by either solution coating or vacuum deposition. Despite this, there continues to be an intriguing stability gap. In this work, we investigate this phenomenon with the purpose of identifying its root causes. Electroluminescence, delayed electroluminescence and photoluminescence measurements are used to study and compare between the aging behavior in OLEDs made by spin-coating versus vacuum-deposition. Hole-only devices are also utilized, and employed to study the effects of charges and excitons, separately and combined. The results reveal that the faster degradation of solution-processed devices relative to their vacuum-deposited counterparts under electrical stress is due to a faster molecular aggregation process. Excitons and interactions between them and polarons appear to play a leading role in inducing this phenomenon. Results from these investigations will be presented and discussed.
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 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 | 0.000 |
| 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 | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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 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".