Anisotropic and low damage III-V/Ge heterostructure etching for multijunction solar cell fabrication with passivated sidewalls
Bibliographic record
Abstract
This article presents a complete plasma etching process to etch high aspect ratio patterns on III-V/Ge solar cell heterostructure with low damage for the fabrication of multijunction solar cells with a through cell via contact architecture. A SiCl4/H2 chemistry was studied with different hydrogen dilutions within the plasma (0%, up to 67%) and with different cathode temperatures (20∘C, up to 200∘C). This chemistry choice creates a SiClx-based inhibiting layer on the sidewalls that promotes anisotropic etching through the epitaxial heterostructure. The study suggests that a high hydrogen flow and a low temperature reduce the chemical reactions that create sidewall erosion. A high hydrogen flow appears to provide a hydrogen passivation of the non-radiative defects on the III-V heterostructure sidewall during the etching process. III-V/Ge triple junction solar cells with standard grid line and busbar front and back contacts have been fabricated and via-holes were plasma-etched through the active layers in order to investigate the impact of hydrogen passivation on the photovoltaic performance. The results demonstrate that the hydrogen passivation enables an open-circuit voltage increase that persists even after 5 months. This plasma process can also be used for the mesa etching step on multijunction solar cells with standard contacts. Thus, it could provide an appealing pathway to increase the conversion efficiency of state-of-the-art multijunction solar cells with standard contacts. To complete the etching process, a liner is used to protect the sidewall properties and a time-multiplexed Ge etching process is proposed to finalize the patterning and even open a pathway towards III-V/Ge plasma dicing.
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 | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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".