Interfacial-oxygen-vacancy mediated doping of MoS2 by high-κ dielectrics

Author

Rai, A. ; Valsaraj, A. ; Movva, H.C.P. ; Roy, A. ; Tutuc, E. ; Register, L.F. ; Banerjee, S.K.

Author_Institution

Microelectron. Res. Center, Univ. of Texas at Austin, Austin, TX, USA

fYear

2015

fDate

21-24 June 2015

Firstpage

189

Lastpage

190

Abstract

Dielectric engineering using high-κ oxides, such as atomic layer deposited (ALD) Al₂O_x and HfO_x, has been in widespread use to enhance the mobility of molybdenum disulfide (MoS₂) based field effect transistors (FETs) [1,2]. This performance enhancement of MoS₂ FETs in a high-κ environment is mainly attributed to the screening of Coulomb scattering from charged impurities, as well as the quenching of homopolar phonon modes of MoS₂ [3]. However, the exact mechanism is still unclear. In this work, we demonstrate, using both experiment and theory, the n-doping of MoS₂ mediated by interfacial-oxygen-vacancies at the high-κ-MoS₂ interface, and propose a mechanism for the mobility enhancement effect in MoS₂ devices upon high-κ encapsulation.

Keywords

atomic layer deposition; field effect transistors; molybdenum compounds; semiconductor device manufacture; semiconductor doping; Al₂O_x; Coulomb scattering; FET; HfO_x; MoS₂; atomic layer deposition; dielectric engineering; field effect transistors; high-κ dielectrics; high-κ encapsulation; high-κ oxides; homopolar phonon modes quenching; interfacial-oxygen-vacancy mediated doping; mobility enhancement effect; Atomic layer deposition; Doping; Hafnium compounds; Random access memory; Scattering;

fLanguage

English

Publisher

ieee

Conference_Titel

Device Research Conference (DRC), 2015 73rd Annual

Conference_Location

Columbus, OH

Print_ISBN

978-1-4673-8134-5

Type

conf

DOI

10.1109/DRC.2015.7175626

Filename

7175626