TY - JOUR
T1 - Thin films of the α -quartz SixGe1-xO2 solid solution
AU - Zhou, Silang
AU - Antoja-Lleonart, Jordi
AU - Ocelík, Václav
AU - Noheda, Beatriz
N1 - Funding Information:
The authors are grateful to Hanna Postma and Rian Lenting for their contribution in the synthesis and analysis of the PLD targets; Kim van Adrichem for the high temperature XRD measurements; Ir.Jacob Baas for the technical support and to Adrian Carretero-Genevrier, Kit de Hond, Gertjan Koster and Guus Rijnders for useful discussions. This work is part of the research programme TOP-PUNT grant with project number 718.016002, which is financed by the Dutch Research Council (NWO).
Publisher Copyright:
© 2022, The Author(s).
PY - 2022/12
Y1 - 2022/12
N2 - SiO2 with the α-quartz structure is one of the most popular piezoelectrics. It is widely used in crystal oscillators, bulk acoustic wave (BAW) devices, surface acoustic wave (SAW) devices, and so on. GeO2 can also be crystallized into the α-quartz structure and it has better piezoelectric properties, with higher piezoelectric coefficient and electromechanical coupling coefficients, than SiO2. Experiments on bulk crystals and theoretical studies have shown that these properties can be tuned by varying the Si/Ge ratio in the SixGe1-xO2 solid solution. However, to the best of our knowledge, thin films of SixGe1-xO2 quartz have never been reported. Here we present the successful crystallization of SixGe1-xO2 thin films in the α-quartz phase on quartz substrates (SiO2) with x up to 0.75. Generally, the films grow semi-epitaxially, with the same orientation as the substrates. Interestingly, the Si0.75Ge0.25O2 composition grows fully strained by the quartz substrates and this leads to the formation of circular quartz domains with an ordered Dauphiné twin structure. These studies represent a first step towards the optimization of piezoelectric quartz thin films for high frequency (> 5 GHz) applications.
AB - SiO2 with the α-quartz structure is one of the most popular piezoelectrics. It is widely used in crystal oscillators, bulk acoustic wave (BAW) devices, surface acoustic wave (SAW) devices, and so on. GeO2 can also be crystallized into the α-quartz structure and it has better piezoelectric properties, with higher piezoelectric coefficient and electromechanical coupling coefficients, than SiO2. Experiments on bulk crystals and theoretical studies have shown that these properties can be tuned by varying the Si/Ge ratio in the SixGe1-xO2 solid solution. However, to the best of our knowledge, thin films of SixGe1-xO2 quartz have never been reported. Here we present the successful crystallization of SixGe1-xO2 thin films in the α-quartz phase on quartz substrates (SiO2) with x up to 0.75. Generally, the films grow semi-epitaxially, with the same orientation as the substrates. Interestingly, the Si0.75Ge0.25O2 composition grows fully strained by the quartz substrates and this leads to the formation of circular quartz domains with an ordered Dauphiné twin structure. These studies represent a first step towards the optimization of piezoelectric quartz thin films for high frequency (> 5 GHz) applications.
UR - http://www.scopus.com/inward/record.url?scp=85124264408&partnerID=8YFLogxK
U2 - 10.1038/s41598-022-05595-z
DO - 10.1038/s41598-022-05595-z
M3 - Article
C2 - 35132092
AN - SCOPUS:85124264408
SN - 2045-2322
VL - 12
JO - Scientific Reports
JF - Scientific Reports
IS - 1
M1 - 2010
ER -