Method for inferring the mechanical strain of GaN-on-Si epitaxial layers using optical profilometry and finite element analysis
| Autor: | David J. Wallis, M. Toon, Martin D. Dawson, Benoit Guilhabert, Simon M. Fairclough, Bogdan F. Spiridon, Ian Watson, Michael J. Strain, Saptarsi Ghosh, A. Hinz, Rachel A. Oliver |
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| Přispěvatelé: | Fairclough, Simon [0000-0003-3781-8212], Wallis, David [0000-0002-0475-7583], Oliver, Rachel [0000-0003-0029-3993], Apollo - University of Cambridge Repository |
| Rok vydání: | 2021 |
| Předmět: |
Materials science
Fabrication business.industry Multiphysics 02 engineering and technology Nitride 021001 nanoscience & nanotechnology 01 natural sciences 4016 Materials Engineering Electronic Optical and Magnetic Materials law.invention 010309 optics QC350 Stack (abstract data type) law Transfer printing 0103 physical sciences Ultimate tensile strength Optoelectronics Wafer Photolithography 0210 nano-technology business 40 Engineering |
| ISSN: | 2159-3930 |
| DOI: | 10.17863/cam.68242 |
| Popis: | GaN-on-Si has become a useful fabrication route for many GaN devices and applications, but the mechanical stress incorporated throughout the material stack can impact the viability of this approach. The transfer printing of GaN membrane devices, a promising emerging technology, is most effective with flat membranes, but in practice many GaN structures released from their Si substrate are highly bowed due to the strain in the epitaxial nitride stack. Our approach uses the optical profiles of epitaxial wafers and membranes as inputs for inferring the mechanical strain state of the material by multi-variable numerical model fitting using COMSOL Multiphysics. This versatile, adaptable and scalable method was tested on samples from two GaN-on-Si wafers, revealing the relationship between built-in strain and material bow in principal-component fashion, returning 3–4×10−4 strain estimates for the AlGaN (compressive) and GaN (tensile) layers, and suggesting the occurrence of plastic deformation during transfer printing. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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