Two dimensional materials for spintronic and nanoelectronic applications
- Datum: 11.06.2018
- Uhrzeit: 14:00
- Vortragende(r): Abdul Wajid Awan
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf
- Ort: Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, 06120 Halle (Saale)
- Raum: New Lecture Hall, Building B
Two-dimensional (2D) materials have recently been explored for their potential role in next- generation nanoelectronic and spintronic applications. Among the class of 2D materials, atomically thin insulator hexagonal boron nitride (h-BN) constitutes a new paradigm due to a large band gap along with its atomically at nature without dangling bonds or interface trap states which make it an ideal candidate for tunnel spin transport in spintronic devices. Despite the rapid progress in 2D materials area of re- search, a semiconducting molybdenum disul de (MoS2) which belongs to the family of layered transition metal dichalcogenides (TMDCs) have recently been drawn signi cant attention for novel nanoelectronic and optoelectronic applications.
The rst part of the talk is the demonstration of developed technique in this research work for implementing the tunneling of spin-polarized electrons via large area CVD grown monolayer h- BN as spin tunnel barrier by interfacing with silicon and ferromagnetic materials. Such 2D h-BN tunnel barrier devices were fabricated over a chip scale by lithography technique and magnetotransport measurements were performed to realize the e cient spin- injection into silicon and to observe the tunnel magnetoresistance (TMR) phenomena at room temperature in magnetic tunnel junction (MTJ) devices. The next part of the talk is focus on key challenge about the nature of charge transport phenomena in molybdenum disul de (MoS2) based eld e ect transistor (FET) nanodevices which remains elusive. Because the ability to realize the modi cation of materials at atomic scale dimension is crucial to fabrication of nanoscale building blocks for novel nanoelectronic devices. As the thinner specimen has less damage extension, therefore 2D materials provide an ideal platform to realize the atomic scale modi cation. In this research work, the key focus is to explore the physical properties of materials which can be greatly a ected and modi ed in a controlled way by irradiation induced defects. Standard electron beam lithography (EBL) technique was used to pattern the contacts on CVD grown monolayer MoS2 nano akes to fabricate FET nanodevices. The electrical charge transport measurements were performed at cryogenic temperature regime. Such FET nanodevices was controllably modify by rastering the helium (He) ion beam of dif- ferent uences inducing the defects locally in the active channel area that introduces a high anisotropy to observe the signi cant variation in conductance value for enhancement of transistor device performance.