Interconnect layers face the dual challenges of electro migration failure and increasing resistivity, as integrated circuit feature sizes enter the nanometer scale. This study focuses on the application research of aluminum and aluminum-based alloys in electronic materials under low power conditions. Al, AlSi, and AlSiCu thin films were prepared using magnetron sputtering technology under various sputtering power conditions. A systematic investigation was made on the influence of power parameters on the regulation of film surface morphology, electrical properties, and crystal structure. Results indicate that the films deposited at lower sputtering power exhibit densely packed, smooth grains with a small root mean square roughness. As the power increases (15–100 W), the surface roughness Ra value rises from 0.8 nm to 1.8 nm. All three materials exhibit a common trend in electrical properties: an increase in carrier concentration and a decrease in mobility. Al films prepared at low power (20 W) demonstrate optimal conductivity, with a resistivity as low as 3.58 μΩ·cm. When the power reaches 100 W, the film performance tends to stabilize, with resistivity maintained around 10.3 μΩ·cm and mobility decreasing by approximately 43%. The effect of alloying elements on the surface and structure of the films was discussed based on the electronic structure.