Space charge limited conduction in ultrathin PbS quantum dot solid diodes
- Nanomechanical Systems Research Division, Korea Institute of Machinery and Materials, Yuseong-gu, Daejeon 305-343 (Korea, Republic of)
As a simple and direct characterization of carrier transport in nanocrystal quantum dot (NQD) solids, current-voltage characterization of ultrathin diodes is proposed. We found the space charge limited conduction (SCLC) behavior in ultrathin PbS NQD diodes with active layer thickness half of the full depletion width; and extracted hole concentrations in the order of 10{sup 15} cm{sup −3}, hole mobilities from 10{sup −4} to 10{sup −5} cm{sup 2}/Vs, trap energy depths varying from 140 meV to 200 meV, and volume trap density around 10{sup 17} cm{sup −3} for thin films with NQDs of diameters 3.3 and 3.6 nm, respectively. We further discuss the validity of applying SCLC to the NQD solids based diodes and the implications of the extracted parameters extensively. Proposed characterization method here is a direct measure of carrier transport in solar cell structures which could provide exact directions in NQD solids based solar cell fabrication and modeling.
- OSTI ID:
- 22278160
- Journal Information:
- Journal of Applied Physics, Vol. 115, Issue 5; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Nanocrystal quantum dots: building blocks for tunable optical amplifiers and lasers
Systematic Merging of Nonfullerene Acceptor π-Extension and Tetrafluorination Strategies Affords Polymer Solar Cells with >16% Efficiency