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

• US 8,422,266 B2
• Filed: 09/12/2012
• Issued: 04/16/2013
• Est. Priority Date: 01/07/2005
• Status: Active Grant

• Current Assignee: InVisage Technologies, Inc. (Apple Inc.)
• Original Assignee: InVisage Technologies, Inc. (Apple Inc.)
• Inventors: Sargent, Edward, Clifford, Jason, Konstantatos, Gerasimos, Howard, Ian, Klem, Ethan J. D., Levina, Larissa
• Primary Examiner(s): Byrne, Harry W
• Application Number:
  US13/612,103
• Publication Number:
  US 20130009129A1
• Time in Patent Office: 216 Days
• Field of Search: 365/106, 365/129, 365/200, 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, 252/301.4, 252/301.6, 977/708, 977/774, 977/775, 977/773, 977/778, 977/759, 977/847, 977/933, 372/43, 435/472, 385/122
• US Class Current: 365/129
• 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. An image sensor, comprising:

an integrated circuit having a plurality of pixel electrodes;

a first layer in electrical communication with the plurality of pixel electrodes, the first layer including an optically sensitive material; and

a second layer coupled to the first layer.

2. The image sensor of claim 1, wherein the second layer is an electrical layer.

3. The image sensor of claim 1, wherein the second layer is configured to make an electrical contact with the first layer.

4. The image sensor of claim 1, wherein the second layer comprises at least one of the following materials including indium tin oxide, tin oxide, tungsten oxide, aluminum, gold, magnesium, platinum, copper, or combinations or layer structures thereof.

5. The image sensor of claim 4, wherein the second layer further comprises at least one of the following oxides including an oxide of magnesium, an oxide of aluminum, an oxide of gold, an oxide of platinum, and an oxide of copper.

6. The image sensor of claim 1, wherein the second electrical layer is an antireflection coating.

7. The image sensor of claim 6, wherein the antireflection coating comprises at least two dielectric layers.

8. The image sensor of claim 1, wherein the second layer is a substantially nonabsorbing dielectric layer.

9. The image sensor of claim 1, wherein the second layer forms at least a portion of a microcavity.

10. The image sensor of claim 1, wherein the second layer is an encapsulation layer.

11. The image sensor of claim 10, wherein the encapsulation layer is configured to protect materials from environmental oxygen.

12. The image sensor of claim 10, wherein the encapsulation layer is configured to protect materials from humidity.

13. The image sensor of claim 1, wherein the second layer is an optical filter.

14. The image sensor of claim 13, wherein the optical filter is configured to allow visible light to pass and to substantially prevent infrared light from passing.

15. The image sensor of claim 13, wherein the optical filter is configured to allow infrared light to pass and to substantially prevent visible light from passing.

16. The image sensor of claim 13, wherein the optical filter is a bandpass filter.

17. The image sensor of claim 1, wherein the first layer includes at least one layer configured for electron injection.

18. The image sensor of claim 1, wherein the first layer includes at least one layer configured to block electrons.

19. The image sensor of claim 1, wherein the first layer includes at least one layer configured for hole injection.

20. The image sensor of claim 1, wherein the first layer includes at least one layer configured to block holes.

21. The image sensor of claim 1, wherein the first layer includes at least one material from the list of materials including quantum dot nanocrystals, semiconductor polymer, MEH-PPV, P3OT, P3HT, and mixtures thereof.

22. The image sensor of claim 21, wherein the responsivity of the image sensor to different optical wavelengths is tunable by changing a size of the quantum dot nanocrystals in the device.

23. The image sensor of claim 21, further comprising a substantially contiguous interface between a the first layer including quantum dot nanocrystals and the integrated circuit underlying the first layer.

24. The image sensor of claim 1, wherein a size of the plurality of pixel electrodes is one square micron or less.

25. The image sensor of claim 1, wherein portions of the optically sensitive material that overlie the integrated circuit continuously overlap and contact at least some features of the integrated circuit.

26. The image sensor of claim 1, wherein the optically sensitive material is to overlie and conform to three-dimensional features of the integrated circuit.

27. The image sensor of claim 1, wherein the plurality of pixel electrodes contact the optically sensitive layer and are configured to relay information regarding the amount of light incident on the optically sensitive material to a readout circuit.

28. The image sensor of claim 1, wherein a fill factor of the optically sensitive material approaches about 100%.

29. The image sensor of claim 1, wherein the first layer including the optically sensitive material is produced by solution-coating onto a pre-fabricated integrated circuit.

30. The image sensor of claim 1, wherein the plurality of pixel electrodes and the first layer including the optically sensitive material form a two-dimensional array of pixels.

31. The image sensor of claim 1, wherein each of the plurality of pixel electrodes is configured to be electronically read-out by a read-out circuit that is in electrical communication with the plurality of pixel electrodes.

32. The image sensor of claim 1, wherein a signal produced by the integrated circuit corresponds to an image.

33. The image sensor of claim 1, wherein a sequence of information from the integrated circuit corresponds to an intensity of light on different regions of the integrated circuit during an exposure period.

34. The image sensor of claim 1, wherein the optically sensitive material is monolithically integrated onto the integrated circuit

35. The image sensor of claim 1, wherein the second layer is substantially opaque in at least a portion of the optical spectrum.