Analysis of trap state densities at HfO2/In0.53Ga0.47As interfaces

AbstractIn this work, we investigate the electrical and dielectric response of lead sulfide (PbS) nanoparticle (NP) films with impedance spectroscopy. In particular, the influence of the ligand passivation on the surface trap state density of PbS NPs is demonstrated by comparing two different types of ligands: ethane-1,2-dithiol (EDT) and 3-sulfanylpropanoic acid (MPA). We observe that the MPA treatment passivates the PbS surface more efficiently than EDT. By analyzing the dielectric loss spectra, we are able to visualize shallow trap states in the bulk of PbS-EDT films and correlate this with the dispersive response observed in the impedance spectra. Evidence of deep trap states is revealed for both PbS-EDT and PbS-MPA diodes. Under illumination, the PbS-MPA and PbS-EDT films demonstrate almost identical trap profiles, showing solely the deep trap state densities. We conclude that the deep traps are related to the stoichiometry of the PbS NPs.

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Enhancing moisture tolerance in efficient hybrid 3D/2D perovskite photovoltaics

Journal of Materials Chemistry A ◽

10.1039/c7ta09657g ◽

2018 ◽

Vol 6 (5) ◽

pp. 2122-2128 ◽

Cited By ~ 74

Author(s):

Teck Ming Koh ◽

Vignesh Shanmugam ◽

Xintong Guo ◽

Swee Sien Lim ◽

Oliver Filonik ◽

...

Keyword(s):

Conversion Efficiency ◽

High Efficiency ◽

Trap State ◽

Successful Strategy ◽

2D Structure ◽

State Densities ◽

The Stability ◽

Improve Stability

Hybrid 3D/2D perovskites combine the high efficiency of 3D perovskites and the stability of 2D perovskites, and possess longer photoluminescence lifetimes, lower trap-state densities and enhanced moisture tolerance. The hybrid 3D/2D structure is a successful strategy to improve stability without sacrificing conversion efficiency.

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Effects of crystallization on trap state densities at grain boundaries in polycrystalline silicon

IEEE Electron Device Letters ◽

10.1109/edl.1987.26662 ◽

1987 ◽

Vol 8 (8) ◽

pp. 368-370 ◽

Cited By ~ 9

Author(s):

S. Seki ◽

O. Kogure ◽

B. Tsujiyama

Keyword(s):

Grain Boundaries ◽

Polycrystalline Silicon ◽

Trap State ◽

State Densities

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Extra long electron–hole diffusion lengths in CH3NH3PbI3−xClx perovskite single crystals

Journal of Materials Chemistry C ◽

10.1039/c7tc02802d ◽

2017 ◽

Vol 5 (33) ◽

pp. 8431-8435 ◽

Cited By ~ 34

Author(s):

Fengying Zhang ◽

Bin Yang ◽

Yajuan Li ◽

Weiqiao Deng ◽

Rongxing He

Keyword(s):

Single Crystals ◽

Diffusion Length ◽

Energy Levels ◽

Trap State ◽

Electron Hole ◽

Carrier Transfer ◽

State Densities

Both trap-state densities and energy levels affect carrier transfer, resulting in a maximum diffusion length of 380 μm in CH3NH3PbI3−xClx (x = 0.005).

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