Fabrication of capacitive pressure sensor using single crystal diamond cantilever beam

Abstract

Fabrication of single crystal diamond capacitive pressure sensor is presented. Firstly, the single crystal diamond cantilever beam was formed on HPHT diamond substrate by using selective high-energy ion implantation, metal patterning, ICP etching and electrochemical etching techniques. Secondly, on this diamond cantilever beam, the desired electrode patterns were processed with photolithography and metal evaporation methods. Furthermore, the displacements of cantilever beam under different pressure conditions were investigated by atomic force microscopy. The capacitance-voltage curves of single crystal diamond cantilever beam and substrate under different force loading conditions were measured by using Agilent B1505A parameter analyzer. The results show that sensitivity increases with the enlargement of electrode area of cantilever beam, and decreases with the rise of measurement frequency.

Recent Progress on Flexible Capacitive Pressure Sensors: From Design and Materials to Applications

“…This principle has resulted in multiple applications for MEMS and flexible pressure sensors. [ 39,65–69 ] Moreover, polymer and paper cantilevers are being utilized to design low‐cost pressure sensors due to advancements in emerging fabrication techniques. [ 39,70–74 ] The width to length ratio, that is, aspect ratio, of a capacitive pressure sensor fabricated from metal coated polymer and double‐sided post‐it tape using do‐it‐yourself (DIY) emerging fabrication technique, plays an important role for sensing/actuation which has been analyzed for acoustic pressure sensing.…”

Beyond biology: alternative uses of cantilever-based technologies

“…To overcome this problem and provide better chemical and thermal stability, Fu et al developed a single crystal diamond capacitive sensor by applying selective high-energy ion implantation, inductive coupled plasma (ICP) etching and electrochemical etching, and metal evaporation techniques. 151 Besides, Subbiah et al worked on the thermal stability of cantilever-based pressure sensors using different materials, 152 which included a ceramic substrate, a glass solder, and high temperature resistant metals.…”

Diamond MEMS: From Classical to Quantum

“…Compared to SCD, polycrystalline diamonds (PCDs) including MCD and NCD/UNCD suffered from the disadvantages of many grains and grain boundaries, impurities, and limited control over their properties, which leads to high internal loss, inferior electronics properties, and the degradation in reliability. [53,54] SCD can make full use of the ultimate properties of diamond in every aspect for MEMS application with high performance and high reliability. In addition, SCD offers a platform for defect spin centers such as NV centers to achieve long quantum coherence times, [55] which makes it promising for quantum applications involving a MEMS resonator coupled with a spin center.…”