Quantum dot optical devices with enhanced gain and sensitivity and methods of making same

Patent metadata

Field	Value
Publication number	US-9570502-B2
Application number	US-201615187275-A
Country	US
Kind code	B2
Filing date	Jun 20, 2016
Priority date	Apr 19, 2004
Publication date	Feb 14, 2017
Grant date	Feb 14, 2017

Abstract

Various embodiment include optical and optoelectronic devices and methods of making same. Under one aspect, an optical device includes an integrated circuit having an array of conductive regions, and an optically sensitive material over at least a portion of the integrated circuit and in electrical communication with at least one conductive region of the array of conductive regions. Under another aspect, a film includes a network of fused nanocrystals, the nanocrystals having a core and an outer surface, wherein the core of at least a portion of the fused nanocrystals is in direct physical contact and electrical communication with the core of at least one adjacent fused nanocrystal, and wherein the film has substantially no defect states in the regions where the cores of the nanocrystals are fused. Additional devices and methods are described.

First claim

What is claimed is:

1. A method of making an image sensor, the method comprising:
providing an integrated circuit having a top surface and an array of electrodes located therein, at least some of the array electrodes being arranged to convey signals from the array to an output; and
depositing an electrically active layer onto at least a portion of the top surface of the integrated circuit such that it is in direct and continuous electrical contact with the at least a portion.

2. The method of claim 1 , wherein the depositing of the electrically active layer is selected from at least one deposition method including spray-coating, dip-casting, drop-casting, evaporating, blade-casting, and spin-coating the electrically active layer onto the at least a portion of the top surface of the integrated circuit.

3. The method of claim 1 , wherein the electrically active layer is optically sensitive.

4. The method of claim 1 , wherein at least some of the electrodes of the integrated circuit are configured to define optical pixels which are to be read by others of the electrodes.

5. The method of claim 1 , wherein a wavelength region of the electromagnetic spectrum is selected in which the electrically active layer is to operate.

6. The method of claim 5 , wherein the selection of the wavelength region includes selecting nanocrystals of a particular size and including them in the electrically active layer.

7. The method of claim 5 , wherein the wavelength region includes at least one wavelength selected from wavelengths of x-ray, infrared, visible, and ultraviolet regions of the electromagnetic spectrum.

8. The method of claim 1 , wherein at least one electrode from the array of electrodes is provided over and in electrical contact with at least a portion of the electrically active layer.

9. The method of claim 8 , wherein the at least one electrode is at least partially optically transparent.

10. The method of claim 8 , wherein the at least one electrode includes at least one filter selected from a bandpass filter and a bandblock filter.

11. The method of claim 8 , wherein the at least one electrode includes at least one material selected from materials including indium tin oxide, indium oxide, tungsten oxide, aluminum, gold, platinum, silver, magnesium, copper, and combinations and layer structures thereof.

12. The method of claim 8 , further comprising forming an anti-reflection coating over the electrically active layer.

13. The method of claim 8 , further comprising forming a protective coating over the electrically active layer to protect the layer from one or more environmental influences.

14. The method of claim 8 , further comprising forming an optical filter over the electrically active layer, wherein the optical filter includes at least one filter selected from a bandpass filter and a bandstop filter.

15. The method of claim 1 , wherein the integrated circuit includes a flexible substrate and is formed in a non-planar shape.

16. The method of claim 1 , wherein the integrated circuit includes at least one of a semiconducting organic molecule and a semiconducting polymer; the integrated circuit includes at least one material selected from materials including silicon, silicon-on-insulator, silicon-germanium, indium phosphide, indium gallium arsenide, gallium arsenide, glass, and polymer.

17. The method of claim 1 , wherein the image sensor includes a plurality of electrodes; and an optically sensitive layer formed between, in contact with, and in electrical communication with the electrodes, the electrodes to provide a signal indicative of radiation absorbed by the optically sensitive layer, the optically sensitive layer providing a photoconductive gain of at least about 100 A/W.

18. The method of claim 1 , wherein the optically sensitive layer has a noise equivalent exposure of less than about 10 −11 J/cm 2 at wavelengths between 400 nm and 800 nm.

19. The method of claim 1 , wherein the optically sensitive layer has a noise equivalent exposure of between about 10 −11 J/cm 2 to about 10 −12 J/cm 2 at wavelengths between 400 nm and 800 nm.

20. The method of claim 1 , wherein the optically sensitive layer has a noise equivalent exposure of less than about 10 −10 J/cm 2 at wavelengths between about 400 nm and about 1400 nm.

21. The method of claim 1 , wherein the electrically active layer is patterned by self-assembling the electrically active layer onto one or more selected regions of the at least a portion.

22. The method of claim 1 , further comprising:
depositing the electrically active layer is deposited over protrusions and trenches in the integrated circuit;
planarizing the electrically active layer to remove portions of the layer from the protrusions, leaving portions of the electrically active layer in the trenches; and
wherein the array of electrodes includes three-dimensional features and the electrically active layer conforms to the three-dimensional features.

Assignees

• Invisage Technologies Inc

Inventors

• Sargent Edward Hartley
• Clifford Jason Paul
• Konstantatos Gerasimos
• Howard Ian
• Klem Ethan J D
• Levina Larissa

Classifications

• H10P14/3461

  Nanoparticles · CPC title

• H10P14/3402

  characterised by the chemical composition · CPC title

• H10P14/265

  using solutions · CPC title

• Y10S977/954

  Of radiant energy · CPC title

• Y10S977/774

  Exhibiting three-dimensional carrier confinement, e.g. quantum dots · CPC title