Preparation of high-quality self-supporting aluminum films using a poly(α-methylstyrene) sacrificial layer

Aluminum (Al) is one of the most promising candidate materials for fabricating Z-pinch inertial confinement fusion loads. However, the achievement of the micrometer-thick self-supporting Al film with excellent structural uniformity and stability remains a significant challenge. In this work, self-supporting Al films with a thickness of 2 μm were obtained via the magnetron sputtering deposition of Al on degradable poly(α-methylstyrene) substrates. By tuning the deposition parameters and annealing processes, the mechanical and electrical properties of the films were further optimized. Lower working pressure favors grain refinement in the Al films, with the most compact structure and optimal mechanical strength achieved at a pressure of 0.4 Pa. After annealing at 400 °C, the films exhibit a significant enhancement in electrical conductivity, showing only a 15% variation in conductivity when bent to a diameter of 4 mm. Furthermore, the films demonstrate excellent structural stability during 50 cyclic bending tests with a bending diameter of 8 mm. These results provide a new approach for realizing highly stable Z-pinch inertial confinement fusion load films and high-performance self-supporting Al films.