Within the seek for lead-free, Si-microfabrication-compatible piezoelectric supplies, skinny movies of scandium-doped aluminum nitride (Al,Sc)N are of nice curiosity to be used in actuators, vitality harvesting, and micro-electromechanical-systems (MEMS).*
Whereas the piezoelectric response of AlN will increase upon doping with Sc, difficulties are encountered throughout movie preparation as a result of, as bulk solids with utterly completely different buildings and enormous variations in cation radii, ScN (rock salt, cubic) and AlN (wurtzite, hexagonal) are immiscible. *
Consequently, (Al,Sc)N is inherently thermodynamically unstable and susceptible to part segregation. Movie preparation is additional sophisticated by the technological requirement for polar [001] or [00 1̲] out-of-plane texture, which is achieved utilizing a seeding layer.*
Within the article “C-Axis Textured, 2–3 μm Thick Al0.75Sc0.25N Movies Grown on Chemically Fashioned TiN/Ti Seeding Layers for MEMS Functions” Asaf Cohen, Hagai Cohen, Sidney R. Cohen, Sergey Khodorov, Yishay Feldman, Anna Kossoy, Ifat Kaplan-Ashiri, Anatoly Frenkel, Ellen Wachtel, Igor Lubomirsky and David Ehre suggest a protocol for efficiently depositing [001] textured, 2–3 µm thick movies of Al0.75Sc0.25N.*
The process depends on the truth that sputtered Ti is [001]-textured α-phase (hcp). Diffusion of nitrogen ions into the α-Ti movie throughout reactive sputtering of Al0.75,Sc0.25N seemingly varieties a [111]-oriented TiN intermediate layer. The lattice mismatch of this very skinny movie with Al0.75Sc0.25N is ~3.7%, offering glorious circumstances for epitaxial development. In distinction to earlier reviews, the Al0.75Sc0.25N movies ready within the present examine are Al-terminated. Low development stress (<100 MPa) permits movies as much as 3 µm thick to be deposited with out lack of orientation or lower in piezoelectric coefficient. *
A bonus of the proposed method is that it’s suitable with a wide range of substrates generally used for actuators or MEMS, as demonstrated right here for each Si wafers and D263 borosilicate glass. Moreover, thicker movies can probably result in elevated piezoelectric stress/pressure by supporting software of upper voltage, however with out enhance within the magnitude of the electrical area. *
SEM, AFM, EDS, XRD and XPS methods have been used for the movie characterization. For the nanoscale topography maps with atomic power microscopy (AFM) NanoWorld Pyrex-Nitride sequence PNP-TRS silicon nitride AFM probes have been utilized in peak-force tapping1® mode. *
*Asaf Cohen, Hagai Cohen, Sidney R. Cohen, Sergey Khodorov, Yishay Feldman, Anna Kossoy, Ifat Kaplan-Ashiri, Anatoly Frenkel, Ellen Wachtel, Igor Lubomirsky and David Ehre
C-Axis Textured, 2–3 μm Thick Al0.75Sc0.25N Movies Grown on Chemically Fashioned TiN/Ti Seeding Layers for MEMS Functions
Sensors 2022, 22, 7041
DOI: https://doi.org/10.3390/s22187041
The article “C-Axis Textured, 2–3 μm Thick Al0.75Sc0.25N Movies Grown on Chemically Fashioned TiN/Ti Seeding Layers for MEMS Functions” by Asaf Cohen, Hagai Cohen, Sidney R. Cohen, Sergey Khodorov, Yishay Feldman, Anna Kossoy, Ifat Kaplan-Ashiri, Anatoly Frenkel, Ellen Wachtel, Igor Lubomirsky and David Ehre is licensed beneath a Artistic Commons Attribution 4.0 Worldwide License, which allows use, sharing, adaptation, distribution and replica in any medium or format, so long as you give acceptable credit score to the unique writer(s) and the supply, present a hyperlink to the Artistic Commons license, and point out if modifications have been made. The pictures or different third-party materials on this article are included within the article’s Artistic Commons license, except indicated in any other case in a credit score line to the fabric. If materials will not be included within the article’s Artistic Commons license and your meant use will not be permitted by statutory regulation or exceeds the permitted use, you will have to acquire permission immediately from the copyright holder. To view a duplicate of this license, go to https://creativecommons.org/licenses/by/4.0/.
1Peak Pressure Tapping® is a registered trademark of Bruker Company.