Mechanical and electromechanical properties of graphene and their potential application in MEMS

Abstract

Graphene-based microelectromechanical systems (MEMS) are very promising candidates for next generation miniaturised, lightweight, and ultra-sensitive devices. In this paper we review the progress to-date of the assessment of the mechanical, electromechanical, thermomechanical properties of graphene towards application in graphene-based MEMS. Graphene possesses a plethora of outstanding properties-such as a 1 TPa Young's modulus, exceptionally high 2D failure strength that stems from its sp 2 hybridization, and strong sigma bonding between carbon atoms. Such exceptional mechanical properties can enable, for example, graphene-based sound sources capable of generating sound beyond the audible range. The recently engineered piezoelectric properties of AFM-tip-pressed graphene membranes or supported graphene on SiO 2 substrates, have paved the way in fabricating graphene-based nanogenerators and actuators.On the other hand, graphene's piezoresistive properties have enabled miniaturized pressure and strain sensors. Two-dimensional graphene nanomechanical resonators can potentially measure

Piezoconductivity of Сhiral Сarbon Nanotubes in the Framework of the Tight-Binding Method

“…Besides, for tubes of large diameter, such as (7,5) and (7,6) at axial tension it is observed oscillatory dependence of M on δ, also corresponding to the features of the band structure of deformed chiral CNTs, described in the previous paragraph.…”

“…The longitudinal component of the tensor of the specific non-phonon conductance of CNTs is calculated within the framework of the Kubo-Greenwood theory [6] with the Green's function formalism [11] application and the use of the tight-binding Hamiltonian model. The final expression for the longitudinal conductivity of CNTs used in the calculations of the constant M has the following form [9]:…”

Stability of suspended monolayer graphene membranes in alkaline environment

“…Therefore it has found specific applications, e.g. in resonators [13][14][15], gas sensors [16], M/NEMS [17,18], pressure drums [19] or ballistic nanodevices [20,21] to name a few.…”

Novel graphene-based optical MEMS accelerometer dependent on intensity modulation

“…These can make a difference in terms of the mechanical, electrical, optical, and thermal properties of the MEMS device, compared to silicon or other materials that are commonly used in the MEMS industry. Furthermore, the highest reported gauge factor (GF) for graphene is 1.8 × 10 4 , whereas this factor is 30-40 for doped polysilicon [21]. Graphene has attracted a lot of attention in recent years, and is expected to significantly impact several technological fields owing to the new applications enabled by its properties [17].…”

“…The Young's modulus of silicon is 169 GPa in the <110> direction and 130 GPa in the <100> direction, which is about 10% of that of graphene, while its tensile strength is much smaller than that of graphene [20]. Furthermore, the highest reported gauge factor (GF) for graphene is 1.8 × 10 4 , whereas this factor is 30-40 for doped polysilicon [21]. In addition to several applications reported recently in [22,23], graphene has also been employed in MEMS owing to its unique mechanical properties [24][25][26].…”