High performance and low-cost graphene vacuum pressure sensor based on one-step laser scribing

Vacuum pressure sensors play a significant role in industry and scientific research. However, there are still many challenges for further application of vacuum pressure sensors due to their complex fabrication and high cost. In this work, we have fabricated a graphene vacuum pressure sensor by one-step laser scribing within 25 min. The resistance of the sensor decreases with declining vacuum pressure. Four linear segments are obtained in the relationship between the resistance response and the vacuum pressure ranging from 7.5 × 10−4 Torr to 2.35 Torr at room temperature. Besides, the graphene sensor exhibits a high sensitivity of 1.2 × 10−2 Torr−1 and a rapid response time of 9 s, which are superior to previously reported sensors. The sensing mechanism of the graphene vacuum pressure sensor is investigated. Under the influence of van der Waals interactions between the stacked graphene multilayers, the void space among the neighboring graphene layers reduces with decreasing vacuum pressure, resulting in a decrease of the sheet resistance. The designed graphene vacuum pressure sensor with the distinguished features of high performance, small size, low cost, and simple fabrication shows great feasibility and tremendous potential for vacuum measurement applications.