Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8032627 | Thin Solid Films | 2018 | 8 Pages |
Abstract
Plasma-enhanced atomic layer deposited (PEALD) aluminum oxide (Al2O3) thin film were investigated with respect to their application in silicon solar cells where not only excellent surface passivation but also excellent electrical insulation properties are required. In this study, the insulation properties of about 10â¯nm to almost 250â¯nm Al2O3 thin films, deposited at temperatures in the range of 100â¯Â°C to 350â¯Â°C and annealed in the range of 250â¯Â°C to 450â¯Â°C, were correlated to various thin film properties, most notably the thin film defect density, i. e. pinhole density, and the thin film stress. Al2O3 thin films provide sufficient electrical insulation after a post-deposition annealing step at 450â¯Â°C when deposited at 250â¯Â°C with thickness of at least 80â¯nm which can be attributed to a low defect density and low stress in the thin films, allowing a low leakage current density and a high breakdown voltage that was independent of the type of metals used for the electrode. Al2O3 thin films deposited and annealed at these temperatures enabled a very good surface passivation of silicon. These results indicate that Al2O3 thin films realized by PEALD are a promising candidate for silicon solar cells that rely on passivating as well as insulating thin films.
Related Topics
Physical Sciences and Engineering
Materials Science
Nanotechnology
Authors
Christian Reichel, Markus Reusch, Stefan Kotula, Filip Granek, Armin Richter, Martin Hermle, Stefan W. Glunz,