TY - JOUR

T1 - Effect of substrate temperature on the mechanical stresses in aluminum nitride films prepared by pulsed DC magnetron sputtering

AU - Шаяпов, Владимир Равильевич

AU - Богословцева, Алена Леонидовна

AU - Чепкасов, Сергей Юрьевич

AU - Капишников, Александр Владимирович

AU - Milekhin, Ilya

AU - Миронова, Мария Ивановна

AU - Гейдт, Павел Викторович

N1 - The work was supported by the Ministry of Science and Higher Education of the Russian Federation (project No. FSUS-2024-0020).

PY - 2025/12/17

Y1 - 2025/12/17

N2 - The purpose of the present work is the investigation of mechanical stress variation in the AlN films deposited by pulsed DC magnetron sputtering under changing of substrate temperature and magnetron power. It has been revealed for the first time that the deposition of AlN films with low mechanical stresses is possible under low values of substrate temperature and magnetron power. A remarkable decrease in mechanical stresses in films from −2.5 GPa to values less than ±300 MPa was found in the case of increasing the film deposition temperature from 60 °C to 300 °C. Comparison of the data obtained by the optical method of measuring the substrate curvature and the XRD method showed that the stress values according to the x-ray diffraction results for films grown at low temperatures (60 °C–100 °C) are significantly higher than those measured by the optical method. This difference can be explained by an increased content of defects for low-temperature films that are shown by results of FTIR spectroscopy, where the absorbance intensity of the E1(TO) mode peak increases with temperature. At the same time, with an increase in the deposition temperature to 275 °C–300 °C, the differences between the XRD and optical data vanish, and the mechanical stresses become small enough and satisfactory for the fabrication of multilayer film bulk acoustic wave resonators.

AB - The purpose of the present work is the investigation of mechanical stress variation in the AlN films deposited by pulsed DC magnetron sputtering under changing of substrate temperature and magnetron power. It has been revealed for the first time that the deposition of AlN films with low mechanical stresses is possible under low values of substrate temperature and magnetron power. A remarkable decrease in mechanical stresses in films from −2.5 GPa to values less than ±300 MPa was found in the case of increasing the film deposition temperature from 60 °C to 300 °C. Comparison of the data obtained by the optical method of measuring the substrate curvature and the XRD method showed that the stress values according to the x-ray diffraction results for films grown at low temperatures (60 °C–100 °C) are significantly higher than those measured by the optical method. This difference can be explained by an increased content of defects for low-temperature films that are shown by results of FTIR spectroscopy, where the absorbance intensity of the E1(TO) mode peak increases with temperature. At the same time, with an increase in the deposition temperature to 275 °C–300 °C, the differences between the XRD and optical data vanish, and the mechanical stresses become small enough and satisfactory for the fabrication of multilayer film bulk acoustic wave resonators.

KW - thin films

KW - mechanical stresses

KW - AlN

KW - magnetron sputtering

M3 - Article

VL - 100

JO - Physica Scripta

JF - Physica Scripta

SN - 0031-8949

IS - 12

M1 - 125935

ER -