Cryogenic etching device based on the conductive cooling method using liquid nitrogen bath

We developed a cryogenic etching device capable of precise temperature control utilizing liquid nitrogen conductive cooling. This device achieves electrode temperatures as low as -170 °C and enables real-time electrode temperature control, providing a reliable alternative to existing cryogenic etching techniques. To demonstrate the performance of our device, we conducted etching experiments on trench-patterned SiO2 thin films, successfully achieving anisotropic etching under cryogenic conditions. Compared with conventional methods such as flowing liquid nitrogen and chillers, our apparatus has a simple electrode structure, eliminates the risk of coolant leakage, and enables real-time temperature control. With these advantages, it is expected that our device based on the liquid nitrogen conductive cooling can be widely used in cryogenic etching research.