Designing High-Performance PbS and PbSe Nanocrystal Electronic Devices through Stepwise, Post-Synthesis, Colloidal Atomic Layer Deposition

Published

February 6, 2014

Author(s)

Soong Ju Oh, Nathaniel E. Berry, Hi-Hyuk Choi, E. A. Gaulding, Hangfei Lin, Taejong Paik, Benjamin T. Diroll, Shinichiro Muramoto, Murray B. Christopher, Cherie R. Kagan

Abstract

We report a facile, solution based, post synthetic colloidal atomic layer deposition (PS-cALD) process to engineer the surface stoichiometry and therefore electronic properties of lead chalcogenide nanocrystal (NC) thin films. Using the stepwise and systematic PS-cALD technique, we introduce a self-limited monolayer shell on lead chalcogenide NCs after their integration as thin films in devices, thereby requiring no further treatment or ligand exchange that unavoidably generates some surface defects. We found that chalcogen enriched NC surfaces are structurally, optically and electronically unstable due to their high surface energy, oxygen sensitivity, and introduction of many midgap and trap states. Lead chloride treatment creates a well-passivated, trap-free shell that stabilizes NCs structurally, optically and electronically, greatly enhancing charge transport. Using PS-cALD of lead chalcogenide NC thin films we demonstrate high electron field effect mobilities of approximately 4.5 cm2/Vs, comparable to record performing devices, without using expensive vacuum-based techniques.

Citation

Nano Letters

Volume

14

Issue

3

Pub Type

Journals

Download Paper

DOI Link

Keywords

nanocrystals, field-effect transistor, atomic layer deposition

Citation

Oh, S. , Berry, N. , Choi, H. , Gaulding, E. , Lin, H. , Paik, T. , Diroll, B. , Muramoto, S. , Christopher, M. and Kagan, C. (2014), Designing High-Performance PbS and PbSe Nanocrystal Electronic Devices through Stepwise, Post-Synthesis, Colloidal Atomic Layer Deposition, Nano Letters, [online], https://doi.org/10.1021/nl404818z (Accessed April 16, 2024)