Reactive sputter deposition of piezoelectric Sc0.12Al0.88N for contour mode resonators
Abstract
Substitution of Al by Sc has been predicted and demonstrated to improve the piezoelectric response in AlN for commercial market applications in radio frequency filter technologies. Although cosputtering with multiple targets have achieved Sc incorporation in excess of 40%, industrial processes requiring stable single target sputtering are currently limited. A major concern with sputter deposition of ScAl is the control over the presence of non-c-axis oriented crystal growth, referred to as inclusions here, while simultaneously controlling film stress for suspended microelectromechanical systems (MEMS) structures. In this paper, we describe 12.5% ScAl single target reactive sputter deposition process and establishes a direct relationship between the inclusion occurrences and compressive film stress allowing for the suppression of the c-axis instability on silicon (100) and Ti/TiN/AlCu seeding layers. An initial high film stress, for suppressing inclusions, is then balanced with a lower film stress deposition to control total film stress to prevent Euler buckling of suspended MEMS devices. Contour mode resonators fabricated using these films demonstrate effective coupling coefficients up to 2.7% with figures of merit of 42. Finally, this work provides a method to establish inclusion free films in ScAlN piezoelectric films for good quality factor devices.
- Authors:
-
- Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). MESA Fabrication Facility
- Publication Date:
- Research Org.:
- Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
- Sponsoring Org.:
- USDOE National Nuclear Security Administration (NNSA)
- OSTI Identifier:
- 1441480
- Alternate Identifier(s):
- OSTI ID: 1436907
- Report Number(s):
- SAND-2018-3433J
Journal ID: ISSN 2166-2746; 662554
- Grant/Contract Number:
- AC04-94AL85000; NA0003525
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Journal of Vacuum Science and Technology B
- Additional Journal Information:
- Journal Volume: 36; Journal Issue: 3; Journal ID: ISSN 2166-2746
- Publisher:
- American Vacuum Society/AIP
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE
Citation Formats
Henry, Michael David, Young, Travis Ryan, Douglas, Erica Ann, and Griffin, Benjamin. Reactive sputter deposition of piezoelectric Sc0.12Al0.88N for contour mode resonators. United States: N. p., 2018.
Web. doi:10.1116/1.5023918.
Henry, Michael David, Young, Travis Ryan, Douglas, Erica Ann, & Griffin, Benjamin. Reactive sputter deposition of piezoelectric Sc0.12Al0.88N for contour mode resonators. United States. https://doi.org/10.1116/1.5023918
Henry, Michael David, Young, Travis Ryan, Douglas, Erica Ann, and Griffin, Benjamin. Fri .
"Reactive sputter deposition of piezoelectric Sc0.12Al0.88N for contour mode resonators". United States. https://doi.org/10.1116/1.5023918. https://www.osti.gov/servlets/purl/1441480.
@article{osti_1441480,
title = {Reactive sputter deposition of piezoelectric Sc0.12Al0.88N for contour mode resonators},
author = {Henry, Michael David and Young, Travis Ryan and Douglas, Erica Ann and Griffin, Benjamin},
abstractNote = {Substitution of Al by Sc has been predicted and demonstrated to improve the piezoelectric response in AlN for commercial market applications in radio frequency filter technologies. Although cosputtering with multiple targets have achieved Sc incorporation in excess of 40%, industrial processes requiring stable single target sputtering are currently limited. A major concern with sputter deposition of ScAl is the control over the presence of non-c-axis oriented crystal growth, referred to as inclusions here, while simultaneously controlling film stress for suspended microelectromechanical systems (MEMS) structures. In this paper, we describe 12.5% ScAl single target reactive sputter deposition process and establishes a direct relationship between the inclusion occurrences and compressive film stress allowing for the suppression of the c-axis instability on silicon (100) and Ti/TiN/AlCu seeding layers. An initial high film stress, for suppressing inclusions, is then balanced with a lower film stress deposition to control total film stress to prevent Euler buckling of suspended MEMS devices. Contour mode resonators fabricated using these films demonstrate effective coupling coefficients up to 2.7% with figures of merit of 42. Finally, this work provides a method to establish inclusion free films in ScAlN piezoelectric films for good quality factor devices.},
doi = {10.1116/1.5023918},
journal = {Journal of Vacuum Science and Technology B},
number = 3,
volume = 36,
place = {United States},
year = {Fri May 11 00:00:00 EDT 2018},
month = {Fri May 11 00:00:00 EDT 2018}
}
Web of Science
Works referencing / citing this record:
Metal‐Organic Chemical Vapor Deposition of Aluminum Scandium Nitride
journal, November 2019
- Leone, Stefano; Ligl, Jana; Manz, Christian
- physica status solidi (RRL) – Rapid Research Letters, Vol. 14, Issue 1