Direct laser writing lithography of photo-insensitive durable GST thin films with near 100% yield

Modern technologies have been heavily reliant on semiconductor chips driving their innovation.These nanoscalefeatured devices have created the need for precise lithographic tools that enable the microscopic patterning of such features.With a large drive to keep the cost of lithography tools low while maintaining high resolution, recent works have explored alternate solutions to existing commercial tools.Therefore, this study investigates a low-cost photothermal lithography technique that utilizes a phase-change material to allow for high-resolution 200 nm features to be patterned.The technique we present in this work does not only provide a sidewall roughness of < 10 nm but also uses light-insensitive materials, allowing for delicate features to be patterned under nonrestrictive environments.We present the theoretical limits of our laser writing system and demonstrate the experimentally achieved features, describing in detail how we overcome some of the diffraction and thermal limits in order to achieve ultimate resolution and sidewall roughness.This was achieved with near 100% yield as every patterned feature survived all stages of the sample processing with minimal defects.