This article examines industrial-scale physical vapor deposition (PVD) manufacturing of shape memory alloy thin films for miniaturized applications. Thin-film shape memory alloys (SMAs) provide multifunctionality by simultaneously serving as substrate, actuator, interconnect, and electrode within single microscale elements. Industrialscale PVD manufacturing enables reproducible fabrication, positioning thin-film SMAs as a platform technology for next-generation adaptive systems in electronics, aerospace, and robotics

Curtis, Sabrina. “Scalable Manufacturing of Thin-Film Shape Memory Alloys for Electronics, Aerospace Systems, and Robotics.” AM&P Technical Articles 183.7 (2025): 42-44.

Auxetic structures provide an interesting approach to solving engineering problems due to their negative Poisson’s ratio, which allows for elongation perpendicular to applied stresses, opposite to a conventional structure’s necking behavior. Thus, they can function well in applications requiring compacting the device into a small volume during the deployment (e.g., implants inserted with catheters) or stretchability with area coverage (e.g., stretchable electronics). Fabricating them with shape memory alloys (SMAs) expands the possibilities. The high strains experienced by auxetic structures may become reversible compared to ordinary metals due to superelastic or shape memory effect.

Dengiz, D., Goldbeck, H., Curtis, S. M., Bumke, L., Jetter, J., & Quandt, E. (2023). Shape memory alloy thin film auxetic structures. Advanced Materials Technologies, 8(12), 2201991

This paper presents a novel approach to smart actuation by integrating
structured superelastic shape memory alloy (SMA) thin-films as electrodes in dielectric elastomer actuators (DEAs), advancing the field of smart material actuation. Traditional DEAs utilize electrodes with embedded conductive particles, such as carbon black, in polydimethylsiloxane (PDMS), which often have low conductivity. By employing TiNiCuCo thin-film electrodes, this study significantly
enhances conductivity. Additionally, the auxetic structure and superelastic properties of these films are leveraged to achieve polymer-compliant low stiffness, large deformation, and necking prevention.

Zemlin, B., Kunze, J., Cozette, B., Curtis, S., Seelecke, S., Quant, E., & Motzki, P. (2025, May). Hybrid smart actuator combining electroactive polymers with superelastic TiNiCuCo. In Electroactive Polymer Actuators, Sensors, and Devices (EAPAD) 2025 (Vol. 13431, pp. 113-118). SPIE

The martensitic phase transformation in Ti₄₀.₄Ni₄₈Hf₁₁.₆ shape memory
alloys is leveraged for bi-directional actuation with TiNiHf/SiO₂/Si composites. The shape memory properties of magnetron sputtered
Ti₄₀.₄Ni₄₈Hf₁₁.₆ films annealed at 635°C – 5 min are influenced by film thickness and the underlying substrate.

Curtis, S.M., Sielenkämper, M., Arivanandhan, G., Dengiz, D., Li, Z.,
Jetter, J., Hanke, L., Bumke, L., Quandt, E., Wulfinghoff, S., and Kohl, M., 2022. TiNiHf/SiO₂/Si shape memory film composites for bidirectional micro actuation. International Journal of Smart and Nano Materials, 13(2), pp.293-314.

Biomagnetic field sensors based on AlN FeCoSiB magnetoelectric (ME) composites desire a resonant frequency that can be precisely tuned to match the biomagnetic signal of interest.

Curtis, S.M., Wolff, N., Dengiz, D., Lewitz, H., Jetter, J., Bumke, L., Hayes, P., Yarar, E., Thormählen, L., Kienle, L. and Meyners, D., 2020. Integration of AlN piezoelectric thin films on ultralow fatigue TiNiCu shape memory alloys. Journal of Materials Research, 35(10), pp.1298-1306.

Patterned planar silicon (Si) semiconductor structures able to conform around 3D surfaces are promising candidates for wearable devices from solar cells to displays. Despite the known anisotropic material properties of crystalline semiconductors, prior evaluations have assumed isotropic stretchable mechanical behavior.

Curtis, S.M., Tompkins, R.P., Nichols, B.M., Graziano, M.B., Kierzewski, I., Smith, G., Leite, M.S. and Lazarus, N., 2019. Structural anisotropy in stretchable silicon. Advanced Electronic Materials, 5(7), p.1900003.