Elastic modulus and coefficient of thermal expansion of piezoelectric Al1−xScxN (up to x = 0.41) thin films
Aluminum scandium nitride (Al1−xScxN with x = 0–0.41) thin films were deposited by reactive pulsed-DC magnetron sputtering on Si(001) and Al2O3(0001) substrates. X-ray diffraction indicated high degree of c-axis orientation in all the films, and based on pole figure measurements, epitaxial relations...
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| Format: | Article |
| Language: | English |
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AIP Publishing LLC
2018-07-01
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| Series: | APL Materials |
| Online Access: | http://dx.doi.org/10.1063/1.5040190 |
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| author | Yuan Lu Markus Reusch Nicolas Kurz Anli Ding Tim Christoph Mario Prescher Lutz Kirste Oliver Ambacher Agnė Žukauskaitė |
| author_facet | Yuan Lu Markus Reusch Nicolas Kurz Anli Ding Tim Christoph Mario Prescher Lutz Kirste Oliver Ambacher Agnė Žukauskaitė |
| author_sort | Yuan Lu |
| collection | DOAJ |
| description | Aluminum scandium nitride (Al1−xScxN with x = 0–0.41) thin films were deposited by reactive pulsed-DC magnetron sputtering on Si(001) and Al2O3(0001) substrates. X-ray diffraction indicated high degree of c-axis orientation in all the films, and based on pole figure measurements, epitaxial relationship could be defined as [101¯0]AlScN//[112¯0]sapphire and (0001)AlScN//(0001)sapphire in films deposited on Al2O3. Piezoelectric coefficient increased up to d33 = 31.6 pC/N in Al0.59Sc0.41N, which is 550% higher than for AlN. The biaxial elastic modulus and the in-plane coefficient of thermal expansion (CTE) as a function of Sc concentration were determined by thermal cycling method: biaxial elastic modulus decreased from 535 GPa in pure AlN to 269 GPa in Al0.59Sc0.41N and CTE was 4.65 × 10−6 K−1 for AlN and 4.29 × 10−6 K−1 for Al0.59Sc0.41N. Additionally, we observed an increase in CTE from 4.18 × 10−6 K−1 at 65 °C to up to 6.38 × 10−6 K−1 at 375 °C for Al0.68Sc0.32N. The experimentally determined CTE and elastic modulus allow a more precise design of Al1−xScxN-based frequency filters which are used in mobile communications and are important parameters for the prediction of device performance at elevated temperatures. |
| first_indexed | 2024-12-23T11:58:58Z |
| format | Article |
| id | doaj.art-4c12139754fe40408cc48e8ca08c652c |
| institution | Directory Open Access Journal |
| issn | 2166-532X |
| language | English |
| last_indexed | 2024-12-23T11:58:58Z |
| publishDate | 2018-07-01 |
| publisher | AIP Publishing LLC |
| record_format | Article |
| series | APL Materials |
| spelling | doaj.art-4c12139754fe40408cc48e8ca08c652c2022-12-21T17:48:01ZengAIP Publishing LLCAPL Materials2166-532X2018-07-0167076105076105-610.1063/1.5040190009807APMElastic modulus and coefficient of thermal expansion of piezoelectric Al1−xScxN (up to x = 0.41) thin filmsYuan Lu0Markus Reusch1Nicolas Kurz2Anli Ding3Tim Christoph4Mario Prescher5Lutz Kirste6Oliver Ambacher7Agnė Žukauskaitė8Fraunhofer Institute for Applied Solid State Physics IAF, Tullastraße 72, 79108 Freiburg, GermanyFraunhofer Institute for Applied Solid State Physics IAF, Tullastraße 72, 79108 Freiburg, GermanyLaboratory for Compound Semiconductor Microsystems, IMTEK—Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee 103, 79110 Freiburg, GermanyFraunhofer Institute for Applied Solid State Physics IAF, Tullastraße 72, 79108 Freiburg, GermanyFraunhofer Institute for Applied Solid State Physics IAF, Tullastraße 72, 79108 Freiburg, GermanyFraunhofer Institute for Applied Solid State Physics IAF, Tullastraße 72, 79108 Freiburg, GermanyFraunhofer Institute for Applied Solid State Physics IAF, Tullastraße 72, 79108 Freiburg, GermanyFraunhofer Institute for Applied Solid State Physics IAF, Tullastraße 72, 79108 Freiburg, GermanyFraunhofer Institute for Applied Solid State Physics IAF, Tullastraße 72, 79108 Freiburg, GermanyAluminum scandium nitride (Al1−xScxN with x = 0–0.41) thin films were deposited by reactive pulsed-DC magnetron sputtering on Si(001) and Al2O3(0001) substrates. X-ray diffraction indicated high degree of c-axis orientation in all the films, and based on pole figure measurements, epitaxial relationship could be defined as [101¯0]AlScN//[112¯0]sapphire and (0001)AlScN//(0001)sapphire in films deposited on Al2O3. Piezoelectric coefficient increased up to d33 = 31.6 pC/N in Al0.59Sc0.41N, which is 550% higher than for AlN. The biaxial elastic modulus and the in-plane coefficient of thermal expansion (CTE) as a function of Sc concentration were determined by thermal cycling method: biaxial elastic modulus decreased from 535 GPa in pure AlN to 269 GPa in Al0.59Sc0.41N and CTE was 4.65 × 10−6 K−1 for AlN and 4.29 × 10−6 K−1 for Al0.59Sc0.41N. Additionally, we observed an increase in CTE from 4.18 × 10−6 K−1 at 65 °C to up to 6.38 × 10−6 K−1 at 375 °C for Al0.68Sc0.32N. The experimentally determined CTE and elastic modulus allow a more precise design of Al1−xScxN-based frequency filters which are used in mobile communications and are important parameters for the prediction of device performance at elevated temperatures.http://dx.doi.org/10.1063/1.5040190 |
| spellingShingle | Yuan Lu Markus Reusch Nicolas Kurz Anli Ding Tim Christoph Mario Prescher Lutz Kirste Oliver Ambacher Agnė Žukauskaitė Elastic modulus and coefficient of thermal expansion of piezoelectric Al1−xScxN (up to x = 0.41) thin films APL Materials |
| title | Elastic modulus and coefficient of thermal expansion of piezoelectric Al1−xScxN (up to x = 0.41) thin films |
| title_full | Elastic modulus and coefficient of thermal expansion of piezoelectric Al1−xScxN (up to x = 0.41) thin films |
| title_fullStr | Elastic modulus and coefficient of thermal expansion of piezoelectric Al1−xScxN (up to x = 0.41) thin films |
| title_full_unstemmed | Elastic modulus and coefficient of thermal expansion of piezoelectric Al1−xScxN (up to x = 0.41) thin films |
| title_short | Elastic modulus and coefficient of thermal expansion of piezoelectric Al1−xScxN (up to x = 0.41) thin films |
| title_sort | elastic modulus and coefficient of thermal expansion of piezoelectric al1 xscxn up to x 0 41 thin films |
| url | http://dx.doi.org/10.1063/1.5040190 |
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