Scalable fabrication of a hybrid field-effect and acousto-electric device by direct growth of monolayer MoS2/LiNbO3

Abstract

Lithium niobate is the archetypical ferroelectric material and the substrate of choice for numerous applications including surface acoustic wave radio frequencies devices and integrated optics. It offers a unique combination of substantial piezoelectric and birefringent properties, yet its lack of optical activity and semiconducting transport hamper application in optoelectronics. Here we fabricate and characterize a hybrid MoS2/LiNbO3 acousto-electric device via a scalable route that uses millimetre-scale direct chemical vapour deposition of MoS2 followed by lithographic definition of a field-effect transistor structure on top. The prototypical device exhibits electrical characteristics competitive with MoS2 devices on silicon. Surface acoustic waves excited on the substrate can manipulate and probe the electrical transport in the monolayer device in a contact-free manner. We realize both a sound-driven battery and an acoustic photodetector. Our findings open directions to non-invasive investigation of electrical properties of monolayer films.

Combined electrical transport and capacitance spectroscopy of a MoS2-LiNbO3 field effect transistor

“…All experimental data is found to be in excellent agreement with an analytical model based on a 2D electron system over the entire range of V GS . Most strikingly we find that for our device the values of µ FE obtained solely from the I SD − V GS overestimates those obtained taking into account the measure C−V GS by more than a factor of ×4.The sample studied consists of 128 • Y-rotated, d = 0.5 mm thick substrate of black lithium niobate (LiNbO 3−x ), on top of which a layer of MoS 2 has been deposited by chemical vapour deposition 18,19 . We use such samples for investigations of the interaction of surface acoustic waves with MoS 2 , as described in ref.…”

“…We use such samples for investigations of the interaction of surface acoustic waves with MoS 2 , as described in ref. 19 .…”

“…We use such samples for investigations of the interaction of surface acoustic waves with MoS 2 , as described in ref. 19 . arXiv:1701.00506v1 [cond-mat.mes-hall] 2 Jan 2017 The sample was characterized by mapping photoluminescence spectroscopy to confirm millimeter-scale growth of MoS 2 .…”

Multi-harmonic quantum dot optomechanics in fused LiNbO3–(Al)GaAs hybrids

“…The transfer of the QDs onto a strong piezoelectric substrate such as LiNbO 3 , with K 2 » 5%, could help enhance the coupling between a semiconductor heterostructure and the SAW field [4]. However, direct epitaxial growth of semiconductors on LiNbO 3 has so far only be achieved for two-dimensional transition metal dichalcogenides [14,30]. Thus, for most semiconductors, such hybrid devices can be fabricated by epitaxial lift-off and transfer of the QD membrane on a LiNbO 3 SAW-chip [31][32][33][34][35][36][37].…”

Optical modulators with 2D layered materials

“…Graphene 124 and other 2D materials (e.g., MoS2 125 ) are attracting growing interest from the field of acoustics. These 2D materials are being considered for the generation, propagation, amplification, and detection of surface acoustic waves 124,125 . This gives an indication that it is technically feasible to conceive 2D material based acousto-optic modulators.…”