A micromachined Joule-Thomson cryocooler has been designed as a cryostage for ice lithography, which allows high-pressure nitrogen throttling to liquefy and fast cool samples with low vibration. The sample can be cooled down to 99.5 K in 30 min and then heated up to room temperature in 10 min. Compared with previous cooling systems based on liquid nitrogen, the Joule-Thomson cryostage has resulted in a significant 90% reduction in cooling time and a decrease in operating temperature by 30 K. Besides, the nitrogen mass-flow rate beneath the sample remains <20 mg/s to minimize vibration. The measured peak-to-peak amplitude at the minimum temperature is about 5.6 nm. As the first cooler integration within an ice lithography system, this Joule-Thomson cryostage not only enables the exploration of a wider range of ice resists, but also can be applied in kinds of microscopes for helping characterize materials at cryogenic temperatures.

中文翻译：

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用于冰光刻的微机械焦耳-汤姆逊制冷机

微机械焦耳-汤姆逊低温冷却器被设计为冰光刻的低温台，它允许高压氮气节流以低振动液化和快速冷却样品。样品可在 30 分钟内冷却至 99.5 K，然后在 10 分钟内加热至室温。与之前基于液氮的冷却系统相比，Joule-Thomson 低温台的冷却时间显着缩短了 90%，工作温度降低了 30 K。此外，样品下方的氮气质量流量保持在 <20 mg/s 以最大限度地减少振动。在最低温度下测得的峰峰值幅度约为5.6 nm。作为冰光刻系统中第一个集成的冷却器，这款焦耳-汤姆逊低温台不仅能够探索更广泛的冰抗蚀剂，而且还可以应用于各种显微镜，以帮助在低温下表征材料。