Boron activation in silicon thin films grown by PECVD under epitaxial and microcrystalline conditions
Boron doping level and boron activation in silicon thin films grown by PECVD under epitaxial (p+ epi‑Si) and microcrystalline (p+ µc-Si) conditions have been investigated as functions of the substrate material and annealing in the range of 200°C – 300°C. Hall effect measurements show that in the as-...
| Main Authors: | , , , |
|---|---|
| 格式: | 文件 |
| 语言: | English |
| 出版: |
Elsevier
2023-12-01
|
| 丛编: | Applied Surface Science Advances |
| 主题: | |
| 在线阅读: | http://www.sciencedirect.com/science/article/pii/S2666523923001423 |
| _version_ | 1827582699145003008 |
|---|---|
| author | Antonio J. Olivares A. Zamchiy V.S. Nguyen P. Roca i Cabarrocas |
| author_facet | Antonio J. Olivares A. Zamchiy V.S. Nguyen P. Roca i Cabarrocas |
| author_sort | Antonio J. Olivares |
| collection | DOAJ |
| description | Boron doping level and boron activation in silicon thin films grown by PECVD under epitaxial (p+ epi‑Si) and microcrystalline (p+ µc-Si) conditions have been investigated as functions of the substrate material and annealing in the range of 200°C – 300°C. Hall effect measurements show that in the as-deposited state, the conductivity is mainly governed by the carrier concentration, while the hole mobility is controlled by the crystalline quality. SIMS measurements reveal that dark conductivity is not directly proportional to the boron doping level, nor to the presence of B-H complexes, suggesting that carbon contamination and the formation of B-O complexes could play an important role in the electrical properties of the material. Annealing in air resulted in an increase in the dark conductivity for all samples. However, the increase was much higher (up to two orders of magnitude) for the samples deposited on silicon-on-insulator (SOI) substrates which have better crystalline quality and displayed the highest increase in hole carrier concentration, related to boron activation. Thus, the substrate material influences both the crystalline quality and the boron incorporation in the p-type material. At high boron incorporation, the mobility limitations are likely to be due to carrier concentration rather than to the crystalline quality, indicating that p+ µc-Si conditions allow a conductivity advantage over p+ epi‑Si conditions due to a higher doping level, which makes them suitable as hole-selective contacts in solar cells. |
| first_indexed | 2024-03-08T22:55:21Z |
| format | Article |
| id | doaj.art-49d44b94dc994bca917227ac909642af |
| institution | Directory Open Access Journal |
| issn | 2666-5239 |
| language | English |
| last_indexed | 2024-03-08T22:55:21Z |
| publishDate | 2023-12-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Applied Surface Science Advances |
| spelling | doaj.art-49d44b94dc994bca917227ac909642af2023-12-16T06:09:32ZengElsevierApplied Surface Science Advances2666-52392023-12-0118100508Boron activation in silicon thin films grown by PECVD under epitaxial and microcrystalline conditionsAntonio J. Olivares0A. Zamchiy1V.S. Nguyen2P. Roca i Cabarrocas3LPICM, CNRS, École Polytechnique, Institut Polytechnique de Paris, Palaiseau 91128, FranceLPICM, CNRS, École Polytechnique, Institut Polytechnique de Paris, Palaiseau 91128, France; Kutateladze Institute of Thermophysics SB RAS, Novosibirsk 630090, RussiaInstitut Photovoltaïque d'Ile-de-France (IPVF), 18 Boulevard Thomas Gobert, Palaiseau 91120, FranceLPICM, CNRS, École Polytechnique, Institut Polytechnique de Paris, Palaiseau 91128, France; Institut Photovoltaïque d'Ile-de-France (IPVF), 18 Boulevard Thomas Gobert, Palaiseau 91120, France; Corresponding author.Boron doping level and boron activation in silicon thin films grown by PECVD under epitaxial (p+ epi‑Si) and microcrystalline (p+ µc-Si) conditions have been investigated as functions of the substrate material and annealing in the range of 200°C – 300°C. Hall effect measurements show that in the as-deposited state, the conductivity is mainly governed by the carrier concentration, while the hole mobility is controlled by the crystalline quality. SIMS measurements reveal that dark conductivity is not directly proportional to the boron doping level, nor to the presence of B-H complexes, suggesting that carbon contamination and the formation of B-O complexes could play an important role in the electrical properties of the material. Annealing in air resulted in an increase in the dark conductivity for all samples. However, the increase was much higher (up to two orders of magnitude) for the samples deposited on silicon-on-insulator (SOI) substrates which have better crystalline quality and displayed the highest increase in hole carrier concentration, related to boron activation. Thus, the substrate material influences both the crystalline quality and the boron incorporation in the p-type material. At high boron incorporation, the mobility limitations are likely to be due to carrier concentration rather than to the crystalline quality, indicating that p+ µc-Si conditions allow a conductivity advantage over p+ epi‑Si conditions due to a higher doping level, which makes them suitable as hole-selective contacts in solar cells.http://www.sciencedirect.com/science/article/pii/S2666523923001423Doping levelThin filmsMicrocrystalline siliconEpitaxial silicon |
| spellingShingle | Antonio J. Olivares A. Zamchiy V.S. Nguyen P. Roca i Cabarrocas Boron activation in silicon thin films grown by PECVD under epitaxial and microcrystalline conditions Applied Surface Science Advances Doping level Thin films Microcrystalline silicon Epitaxial silicon |
| title | Boron activation in silicon thin films grown by PECVD under epitaxial and microcrystalline conditions |
| title_full | Boron activation in silicon thin films grown by PECVD under epitaxial and microcrystalline conditions |
| title_fullStr | Boron activation in silicon thin films grown by PECVD under epitaxial and microcrystalline conditions |
| title_full_unstemmed | Boron activation in silicon thin films grown by PECVD under epitaxial and microcrystalline conditions |
| title_short | Boron activation in silicon thin films grown by PECVD under epitaxial and microcrystalline conditions |
| title_sort | boron activation in silicon thin films grown by pecvd under epitaxial and microcrystalline conditions |
| topic | Doping level Thin films Microcrystalline silicon Epitaxial silicon |
| url | http://www.sciencedirect.com/science/article/pii/S2666523923001423 |
| work_keys_str_mv | AT antoniojolivares boronactivationinsiliconthinfilmsgrownbypecvdunderepitaxialandmicrocrystallineconditions AT azamchiy boronactivationinsiliconthinfilmsgrownbypecvdunderepitaxialandmicrocrystallineconditions AT vsnguyen boronactivationinsiliconthinfilmsgrownbypecvdunderepitaxialandmicrocrystallineconditions AT procaicabarrocas boronactivationinsiliconthinfilmsgrownbypecvdunderepitaxialandmicrocrystallineconditions |