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

• US 9,570,502 B2
• Filed: 06/20/2016
• Issued: 02/14/2017
• Est. Priority Date: 04/19/2004
• Status: Active Grant

• Current Assignee: InVisage Technologies, Inc. (Apple Inc.)
• Original Assignee: InVisage Technologies, Inc. (Apple Inc.)
• Inventors: Sargent, Edward Hartley, Clifford, Jason Paul, Konstantatos, Gerasimos, Howard, Ian, Klem, Ethan J. D., Levina, Larissa
• Primary Examiner(s): Byrne, Harry W
• Application Number:
  US15/187,275
• Publication Number:
  US 20160300880A1
• Time in Patent Office: 239 Days
• Field of Search: 257/1, 257 14- 25, 257/59, 257/72, 257/202, 257/250, 257/E29.071, 257/E25.004, 438/48, 438/197, 438/479, 438/590, 438/962, 438/73, 428/403, 428/407, 385/122, 977/708, 977/774, 977/775, 977/773, 977/778, 977/759, 977/847, 977/933, 372/43, 435/472
• US Class Current: 1/1
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: H01L 2031/0344 Organic materials
• CPC Class Codes: H01L 21/02521 Materials
• CPC Class Codes: H01L 21/02601 Nanoparticles fullerenes H10K85/211
• CPC Class Codes: H01L 21/02628 using solutions
• CPC Class Codes: H01L 27/1462 Coatings
• CPC Class Codes: H01L 27/14634 Assemblies, i.e. Hybrid structures
• CPC Class Codes: H01L 27/14665 Imagers using a photoconductor layer
• CPC Class Codes: H01L 27/14692 Thin film technologies, e.g. amorphous, poly, micro- or nanocrystalline silicon
• CPC Class Codes: H01L 31/02162 for filtering or shielding light, e.g. multicolour filters for photodetectors
• CPC Class Codes: H01L 31/022466 made of transparent conductive layers, e.g. TCO, ITO layers
• CPC Class Codes: H01L 31/0352 characterised by their shape or by the shapes, relative sizes or disposition of the semiconductor regions
• CPC Class Codes: H01L 31/035218 the quantum structure being quantum dots
• CPC Class Codes: H01L 31/03926 comprising a flexible substrate
• CPC Class Codes: H10K 10/466 Lateral bottom-gate IGFETs comprising only a single gate
• CPC Class Codes: H10K 10/488 the channel region comprising a layer of composite material having interpenetrating or embedded materials, e.g. a mixture of donor and acceptor moieties, that form a bulk heterojunction
• CPC Class Codes: H10K 30/30 comprising bulk heterojunctions, e.g. interpenetrating networks of donor and acceptor material domains
• CPC Class Codes: H10K 30/35 : comprising inorganic nanostructures, e.g. CdSe nanoparticles
• CPC Class Codes: H10K 39/30 : Devices controlled by radiation
• CPC Class Codes: H10K 39/36 : Devices specially adapted for detecting X-ray radiation
• CPC Class Codes: H10K 85/114 : Poly-phenylenevinylene; Derivatives thereof
• CPC Class Codes: Y02E 10/549 : Organic PV cells
• CPC Class Codes: Y10S 977/773 : Nanoparticle, i.e. structure having three dimensions of 100 nm or less
• CPC Class Codes: Y10S 977/774 : Exhibiting three-dimensional carrier confinement, e.g. quantum dots
• CPC Class Codes: Y10S 977/893 : Deposition in pores, molding, with subsequent removal of mold
• CPC Class Codes: Y10S 977/954 : Of radiant energy
• CPC Class Codes: Y10S 977/962 : for carrying or transporting

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.

Claims

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/cm² 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/cm² to about 10<sup>−

12</sup> J/cm² 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/cm² 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.