Bare quantum dots superlattice photonic devices

Patent metadata

Field	Value
Publication number	US-9318632-B2
Application number	US-201314080359-A
Country	US
Kind code	B2
Filing date	Nov 14, 2013
Priority date	Nov 14, 2013
Publication date	Apr 19, 2016
Grant date	Apr 19, 2016

Abstract

Manipulation of the passivation ligands of colloidal quantum dots and use in QD electronics. A multi-step electrostatic process is described which creates bare QDs, followed by the formation of QD superlattice via electric and thermal stimulus. Colloidal QDs with original long ligands (i.e. oleic acid) are atomized, and loaded into a special designed tank to be washed, followed by another atomization step before entering the doping station. The final step is the deposition of bare QDs onto substrate and growth of QD superlattice. The method permits the formation of various photonic devices, such as single junction and tandem solar cells based on bare QD superlattice, photodetectors, and LEDs. The devices include a piezoelectric substrate with an electrode, and at least one layer of bare quantum dots comprising group IV-VI elements on the electrode, where the bare quantum dots have been stripped of outer-layer ligands.

First claim

What is claimed is:

1. A thin film device, comprising:
a substrate, having an upper face and a lower face;
a first electrode disposed on the upper face of the substrate;
at least one layer of bare quantum dots comprising group IV-VI elements disposed on the electrode, wherein the bare quantum dots have been stripped of all outer-layer ligands prior to deposition;
wherein the at least one layer of bare quantum dots further comprises at least one alternating layer of n-type bare quantum dots and p-type bare quantum dots; and

a second electrode disposed on the upper face of the at least one layer of bare quantum dots, wherein the first electrode and second electrode have different polarities.

2. The device of claim 1 , wherein the group IV-VI elements are PbTe, PbSe, PbSe—PbTe, SbTe 2 —PbTe, AgSbTe 2 —PbSe, alloys of PbTe and PbSe, PbSn x Se 1-x , or combinations thereof.

3. The device of claim 1 , wherein the substrate is glass, quartz, plastic, polyethylene terephthalate, high density polyethylene, polyvinyl chloride, polypropylene, polystyrene, polyethylene, high impact polystyrene, low density polyethylene, polycarbonate, polyamide, or polyurethane.

4. The device of claim 1 , wherein the at least one layer of bare quantum dots comprises a single-size multi-layer A n , or an alternating multi-layer in the combination of A n B m , where A and B are different sized quantum dots, and n and m are indices for the repeating pattern of the quantum dots.

5. The device of claim 1 , wherein the first electrode is indium tin oxide, zinc oxide, or a titanium oxide.

6. The device of claim 1 , further comprising a PEDOT:PSS or ZnO/TiO 2 layer disposed on the first electrode.

7. The device of claim 1 , wherein the second electrode disposed on the upper face of the at least one layer of bare quantum dots is aluminum, or gold.

8. The device of claim 1 , further comprising a hole transport layer disposed on the at least one layer of bare quantum dots, wherein the hole transport layer is PEDOT:PSS, LiF, MoO 3 , MoOx, or ZnSe/ZnTe.

9. The device of claim 8 , wherein the hole transport layer is MoO 3 or PEDOT:PSS, and wherein
the first electrode further comprises indium tin oxide;
the second electrode further comprises gold or silver; and
a ZnO/TiO 2 or ZnO layer disposed on the first electrode.

10. The device of claim 9 , further comprising a ZnO layer disposed on the at least one layer of bare quantum dots.

Assignees

• Lewis Jason E
• Jiang Xiaomei
• Univ South Florida

Inventors

• Lewis Jason E
• Jiang Xiaomei

Classifications

• H10F77/146

  Superlattices; Multiple quantum well structures · CPC title

• H10F77/127

  comprising only Group IV-VI or only Group II-IV-VI chalcogenide materials, e.g. PbSnTe · CPC title

• H10F71/00

  Manufacture or treatment of devices covered by this subclass (patterning processes to connect thin photovoltaic cells in integrated devices, or assemblies of multiple devices, having photovoltaic cells H10F19/33; manufacture or treatment of encapsulations or containers for integrated devices, or assemblies of multiple devices, having photovoltaic cells H10F19/80; manufacture or treatment of integrated devices, or assemblies of multiple devices, comprising at least one element in which radiation controls the flow of current H10F39/00) · CPC title

• H10F77/1433 Primary

  Quantum dots · CPC title

• H01L31/18

  Electricity · mapped topic