High-precision vacuum sensing is an essential element in various industrial fields such as semiconductor processing and vacuum based packaging. Accordingly, the advancement in vacuum sensing technology that enables both miniaturisation and low power operation is required. Here, we manufactured highly miniaturised Pirani vacuum gauge using the micro-electro-mechanical systems (MEMS) process and verified its performance using various signal processing methods. First, the fabricated gauge was used to measure the pressure response in the range of 102 Torr to 10-5 Torr, and its reliability was verified. Furthermore, using the same measurement setup, we conducted a comparative analysis in the pressure range of 800 mTorr to 15 mTorr between the fabricated gauge and a commercial sensor. Subsequently, the gauge was operated using the unipolar square-wave heating method and its characteristics were compared with those obtained from the sine-wave heating method. Although the unipolar square-wave heating method exhibited slightly lower precision than the sine-wave heating method, it demonstrated reliable performance suitable for practical implementation, along with the benefit of low power operation. Therefore, this method can be effectively applied to various practical vacuum measurement systems due to its advantages such as simple circuit configuration and low power consumption. The fabricated MEMS Pirani vacuum gauge, featuring miniaturisation and low-power characteristics and integrated with the unipolar square-wave heating-based measurement technique, demonstrates potential for applications in industrial fields such as semiconductor processing and vacuum-based packaging.
Jung et al. (Wed,) studied this question.