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This work presents a study of piezoelectric zinc oxide (ZnO) thin films deposited by a novel post‐reactive sputtering method. The process utilizes a rotating drum with DC magnetron sputtering deposition onto substrates with subsequent DC plasma‐assisted oxidation of the deposited metal to metal oxide. The paper analyzes the influence of plasmaassisted magnetron sputtering (PA‐MS) deposition parameters (O2 plasma source power, O2 flow, and Ar flow) on the morphological, structural, optical, and piezoelectric properties of ZnO thin films. Design of experiments has been utilized to evaluate the role of these parameters on the growth rate (rg) and the properties of resulting films. Results indicate a predominant influence of the plasma power on the rg over other parameters. Among the eight tested samples, three of them show high crystal quality with high intensity (0001) diffraction peak, characteristic of the wurtzite crystalline structure of ZnO, and one of them exhibits piezoelectric coefficient values of ≈11pC N−1. That sample corresponding to a ZnO film deposited at the lowest rg of 0.075 nm s−1, confirmed the key role of the deposition parameters on the piezoelectric response of films, and demonstrated PA‐MS as a promising technique to produce high‐quality piezoelectric thin films. [ABSTRACT FROM AUTHOR]

Motion artifacts can be a significant noise source in biomagnetic measurements when magnetic sensors are not separated from the signal source. In ambient environments, motion artifacts can be up to ten times stronger than the desired signals, varying with environmental conditions. This study evaluates the variability of these artifacts and the effectiveness of a gradiometer in reducing them in such settings. To achieve these objectives, we first measured the single channel output in varying magnetic field conditions to observe the effect of homogeneous and gradient background fields. Our analysis revealed that the variability in motion artifact within an ambient environment is primarily influenced by the gradient magnetic field rather than the homogeneous one. Subsequently, we configured a gradiometer in parallel and vertical alignment with the direction of vibration (X-axis). Our findings indicated that in a gradient background magnetic field ranging from 1 nT/mm to 10 nT/mm, the single-channel sensor output exhibited a change of 164.97 pT per mm unit increase, while the gradiometer output showed a change of only 0.75 pT/mm within the same range. Upon repositioning the gradiometer vertically (Y direction), perpendicular to the direction of vibration, the singlechannel output slope increased to 196.85 pT, whereas the gradiometer output only increased by 1.06 pT/mm for the same range. Our findings highlight the influence of ambient environments on motion artifacts and demonstrate the potential of gradiometers to mitigate these effects. In the future, we plan to record biomagnetic signals both inside and outside the shielded room to compare the efficacy of different gradiometer designs under varying environmental conditions. [ABSTRACT FROM AUTHOR]

Motion artifacts can be a significant noise source in biomagnetic measurements when magnetic sensors are not separated from the signal source. In ambient environments, motion artifacts can be up to ten times stronger than the desired signals, varying with environmental conditions. This study evaluates the variability of these artifacts and the effectiveness of a gradiometer in reducing them in such settings. To achieve these objectives, we first measured the single channel output in varying magnetic field conditions to observe the effect of homogeneous and gradient background fields. Our analysis revealed that the variability in motion artifact within an ambient environment is primarily influenced by the gradient magnetic field rather than the homogeneous one. Subsequently, we configured a gradiometer in parallel and vertical alignment with the direction of vibration (X-axis). Our findings indicated that in a gradient background magnetic field ranging from 1 nT/mm to 10 nT/mm, the single-channel sensor output exhibited a change of 164.97 pT per mm unit increase, while the gradiometer output showed a change of only 0.75 pT/mm within the same range. Upon repositioning the gradiometer vertically (Y direction), perpendicular to the direction of vibration, the single-channel output slope increased to 196.85 pT, whereas the gradiometer output only increased by 1.06 pT/mm for the same range. Our findings highlight the influence of ambient environments on motion artifacts and demonstrate the potential of gradiometers to mitigate these effects. In the future, we plan to record biomagnetic signals both inside and outside the shielded room to compare the efficacy of different gradiometer designs under varying environmental conditions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Ghahremani Arekhloo, Wang, Parvizi, Tanwear, Zuo, McKinlay, Garcia Nuñez, Nazarpour and Heidari.)