| AVS 65th International Symposium & Exhibition | |
| 2D Materials Focus Topic | Tuesday Sessions |
| Session 2D+EM+MI+NS-TuM |
| Session: | Properties of 2D Materials including Electronic, Magnetic, Mechanical, Optical, and Thermal Properties |
| Presenter: | Eric Pop, Stanford University |
| Authors: | Pop, Stanford University E. Yalon, Stanford University C. McClellan, Stanford University K. Smithe, Stanford University C. English, Stanford University M. Mleczko, Stanford University M. Muñoz Rojo, Stanford University N. Wang, Stanford University S. Suryavanshi, Stanford University I. Datye, Stanford University C. Bailey, Stanford University A. Gabourie, Stanford University M. Chen, Stanford University V. Chen, Stanford University K. Schauble, Stanford University R. Grady, Stanford University |
| Correspondent: | Click to Email |
This talk will present recent highlights from our research on two-dimensional (2D) materials and devices including graphene, boron nitride (h-BN), and transition metal dichalcogenides (TMDs). The results span from fundamental measurements and simulations, to devices, to system-oriented applications which take advantage of unusual 2D material properties. On the fundamental side, we have measured record velocity saturation in graphene [1,2], as well as the thermal properties of graphene nanoribbons [3]. These are important for electronic applications, which can exhibit substantial self-heating during operation [4]. Taking advantage of low cross-plane thermal conductance, we found unexpected applications of graphene as ultra-thin electrode to reduce power consumption in phase-change memory [5]. We have also demonstrated wafer-scale graphene systems for analog dot product computation [6].
We have grown monolayer 2D semiconductors by chemical vapor deposition over cm2 scales, including MoS2 with low device variability [7], WSe2, MoSe2 – and multilayer TMDs MoTe2 and WTe2 [8]. Importantly, ZrSe2 and HfSe2 have native high-K dielectrics ZrO2 and HfO2, which are of key technological relevance [9]. Improving the electrical contact resistance [10], we demonstrated 10 nm transistors using monolayer MoS2, with the highest current reported to date (>400 µA/µm), approaching ballistic limits [11]. Using Raman thermometry, we uncovered low thermal boundary conductance (~15 MW/m2/K) between MoS2 and SiO2, which could limit heat dissipation in 2D electronics [12]. We are presently exploring unconventional applications including thermal transistors [13], which could enable nanoscale control of heat in “thermal circuits” analogous with electrical circuits. Overall, these studies reveal fundamental limits and new applications that could be achieved with 2D materials, taking advantage their unique properties.
References: [1] V. Dorgan, M.-H. Bae, E. Pop, Appl. Phys. Lett. 97, 082112 (2010). [2] M. Yamoah, et al., ACS Nano 11, 9914 (2017). [3] M.-H. Bae et al., Nature Comm. 4, 1734 (2013). [4] S. Islam, et al., IEEE Electron Device Lett. 34, 166 (2013). [5] A. Behnam et al., Appl. Phys. Letters. 107, 123508 (2015). [6] N. Wang et al., IEEE VLSI Tech. Symp., Jun 2016, Honolulu HI. [7] K. Smithe et al., ACS Nano 11, 8456 (2017). [8] M. Mleczko et al., ACS Nano 10, 7507 (2016). [9] M. Mleczko, E. Pop, et al., Science Adv. 3, e1700481 (2017). [10] C. English et al., Nano Lett. 16, 3824 (2016). [11] C. English et al., IEEE Intl. Electron Devices Meeting (IEDM), Dec 2016. [12] E. Yalon, E. Pop, et al., Nano Lett. 17, 3429 (2017). [13] A. Sood, E. Pop et al. in press (2018).