Conformally Overlaid Ferromagnetic Shadow Masks for Etching and Deposition Processes

The pattern fabrication using a shadow mask does not involve the use of solutions, which is beneficial for scenarios incompatible with wet processes. However, when the shadow mask is partially fixed from its edges, the conformal overlay of the mask may be not ensured, which can give rise to blurred patterns. This study proposes a conformally overlaid ferromagnetic shadow mask (FSM) to the substrate with the help of magnetic force. We identify the strength of the magnetic field that is appropriate for minimizing the inherent gap between the shadow mask and the substrate. Reactive ion etching and electron-beam evaporation processes using a conformally overlaid nickel-cobalt FSM result in processed patterns that exhibit a precise congruence with the mask opening. The development lays the groundwork for more accurate and reliable pattern fabrication without photolithography. [2023-0137]