Printable Composition of a Liquid or Gel Suspension of Diodes

• US 20120161195A1
• Filed: 08/31/2011
• Published: 06/28/2012
• Est. Priority Date: 05/31/2007
• Status: Active Grant

• Current Assignee: NthDegree Technologies Worldwide Inc.
• Original Assignee: NthDegree Technologies Worldwide Inc.
• Inventors: Lowenthal, Mark David, Ray, William Johnstone, Shotton, Neil O., Blanchard, Richard A., Lewandowski, Mark Allan, Oraw, Brad, Baldridge, Jeffrey, Perozziello, Eric Anthony
• Granted Patent: US 8,809,126 B2
• Time in Patent Office: Days
• US Class Current: 257/100
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01L 24/95 at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/09701 Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/12042 LASER
• CPC Class Codes: H01L 2924/13033 TRIAC - Triode for Alternating Current - A bidirectional switching device containing two thyristor structures with common gate contact
• CPC Class Codes: H01L 2924/13034 Silicon Controlled Rectifier [SCR]
• CPC Class Codes: H01L 2924/1305 Bipolar Junction Transistor [BJT]
• CPC Class Codes: H01L 2924/1306 Field-effect transistor [FET]
• CPC Class Codes: H01L 2924/13062 Junction field-effect transistor [JFET]
• CPC Class Codes: H01L 2924/13091 Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: H01L 31/0203 Containers; Encapsulations , e.g. encapsulation of photodiodesfor photovoltaic devices H01L31/048; for organic photosensitive devices H10K30/80
• CPC Class Codes: H01L 31/035236 Superlattices; Multiple quantum well structures
• CPC Class Codes: H01L 31/105 the potential barrier being of the PIN type
• CPC Class Codes: H01L 31/1852 comprising a growth substrate not being an AIIIBV compound
• CPC Class Codes: H01L 31/1856 comprising nitride compounds, e.g. GaN
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/20 : with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/38 : with a particular shape
• CPC Class Codes: H01L 33/56 : Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H10K 30/88 : Passivation; Containers; Encapsulations
• CPC Class Codes: H10K 50/80 : Constructional details
• CPC Class Codes: H10K 50/805 : Electrodes
• CPC Class Codes: H10K 50/84 : Passivation; Containers; Encapsulations
• CPC Class Codes: H10K 59/17 : Passive-matrix OLED displays
• CPC Class Codes: H10K 59/805 : Electrodes
• CPC Class Codes: H10K 59/87 : Passivation; Containers; Encapsulations
• CPC Class Codes: H10K 59/90 : Assemblies of multiple devices comprising at least one organic light-emitting element
• CPC Class Codes: H10K 71/00 : Manufacture or treatment specially adapted for the organic devices covered by this subclass
• CPC Class Codes: H10K 71/13 : using printing techniques, e.g. ink-jet printing or screen printing
• CPC Class Codes: H10K 71/15 : characterised by the solvent used
• CPC Class Codes: Y02E 10/544 : Solar cells from Group III-V materials
• CPC Class Codes: Y02E 10/549 : Organic PV cells

Abstract

An exemplary printable composition of a liquid or gel suspension of diodes comprises a plurality of diodes, a first solvent and/or a viscosity modifier. In other exemplary embodiments a second solvent is also included, and the composition has a viscosity substantially between about 100 cps and about 25,000 cps at about 25° C. In an exemplary embodiment, a composition comprises: a plurality of diodes or other two-terminal integrated circuits; one or more solvents comprising about 15% to 99.9% of any of N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, N-octanol, ethanol, tetrahydrofurfuryl alcohol, cyclohexanol, and mixtures thereof; a viscosity modifier comprising about 0.10% to 2.5% methoxy propyl methylcellulose resin or hydroxy propyl methylcellulose resin or mixtures thereof; and about 0.01% to 2.5% of a plurality of substantially optically transparent and chemically inert particles having a range of sizes between about 10 to about 50 microns.

Claims

1. A composition comprising:

a plurality of diodes;

a first solvent; and

a viscosity modifier.

2. The composition of claim 1, wherein the first solvent comprises at least one solvent selected from the group consisting of:

water;

alcohols such as methanol, ethanol, N-propanol (including 1-propanol, 2-propanol (isopropanol), 1-methoxy-2-propanol), butanol (including 1-butanol, 2-butanol (isobutanol), pentanol (including 1-pentanol, 2-pentanol, 3-pentanol), octanol, N-octanol (including 1-octanol, 2-octanol, 3-octanol), tetrahydrofurfuryl alcohol, cyclohexanol, terpineol;

ethers such as methyl ethyl ether, diethyl ether, ethyl propyl ether, and polyethers;

esters such ethyl acetate, dimethyl adipate, propylene glycol monomethyl ether acetate, dimethyl glutarate, dimethyl succinate, glycerin acetate;

glycols such as ethylene glycols, diethylene glycol, polyethylene glycols, propylene glycols, dipropylene glycols, glycol ethers, glycol ether acetates;

carbonates such as propylene carbonate;

glycerols such as glycerin;

acetonitrile, tetrahydrofuran (THF), dimethyl formamide (DMF), N-methyl formamide (NMF), dimethyl sulfoxide (DMSO); and

mixtures thereof.

3. The composition of claim 1, wherein each diode of the plurality of diodes has a diameter between about 20 to 30 microns and a height between about 5 to 15 microns.

4. The composition of claim 1, wherein each diode of the plurality of diodes has a diameter between about 10 to 50 microns and a height between about 5 to 25 microns.

5. The composition of claim 1, wherein each diode of the plurality of diodes has a width and length each between about 10 to 50 microns and a height between about 5 to 25 microns.

6. The composition of claim 1, wherein each diode of the plurality of diodes has a width and length each between about 20 to 30 microns and a height between about 5 to 15 microns.

7. The composition of claim 1, further comprising:

a plurality of substantially optically transparent and chemically inert particles having a range of sizes between about 10 to about 50 microns and present in an amount of about 0.1% to 2.5% by weight.

8. The composition of claim 1, further comprising:

a plurality of substantially optically transparent and chemically inert particles having a range of sizes between about 10 to about 30 microns and present in an amount of about 0.1% to 2.5% by weight.

9. The composition of claim 1, wherein the first solvent comprises dipropylene glycol.

10. The composition of claim 1, wherein the first solvent comprises N-propanol.

11. The composition of claim 1, wherein the first solvent comprises 1-octanol.

12. The composition of claim 1, wherein the first solvent comprises 1-methoxy-2-propanol.

13. The composition of claim 1, wherein the first solvent comprises propylene glycol.

14. The composition of claim 1, wherein the first solvent is present in an amount of about 0.3% to 50% by weight.

15. The composition of claim 1, wherein the viscosity modifier comprises a methoxy propyl methylcellulose resin or a hydroxy propyl methylcellulose resin or a mixture thereof.

16. The composition of claim 1, wherein the plurality of diodes are light emitting diodes or photovoltaic diodes.

17. The composition of claim 1, wherein the viscosity modifier is present in an amount of about 0.30% to 5% by weight.

18. The composition of claim 1, wherein the viscosity modifier is present in an amount of about 0.10% to 3% by weight.

19. The composition of claim 1, wherein the viscosity modifier comprises at least one viscosity modifier selected from the group consisting of:

clays such as hectorite clays, garamite clays, organo-modified clays;

saccharides and polysaccharides such as guar gum, xanthan gum;

celluloses and modified celluloses such as hydroxy methylcellulose, methylcellulose, ethyl cellulose, propyl methylcellulose, methoxy cellulose, methoxy methylcellulose, methoxy propyl methylcellulose, hydroxy propyl methylcellulose, carboxy methylcellulose, hydroxy ethylcellulose, ethyl hydroxyl ethylcellulose, cellulose ether, cellulose ethyl ether, chitosan;

polymers such as acrylate and (meth)acrylate polymers and copolymers;

glycols such as ethylene glycols, diethylene glycol, polyethylene glycols, propylene glycols, dipropylene glycols, glycol ethers, glycol ether acetates;

fumed silica, silica powders;

modified ureas; and

mixtures thereof.

20. The composition of claim 1, further comprising a second solvent different from the first solvent.

21. The composition of claim 20, wherein the second solvent is at least one solvent selected from the group consisting of:

water;

alcohols such as methanol, ethanol, N-propanol (including 1-propanol, 2-propanol (isopropanol), 1-methoxy-2-propanol), butanol (including 1-butanol, 2-butanol (isobutanol), pentanol (including 1-pentanol, 2-pentanol, 3-pentanol), octanol, N-octanol (including 1-octanol, 2-octanol, 3-octanol), tetrahydrofurfuryl alcohol, cyclohexanol, terpineol;

ethers such as methyl ethyl ether, diethyl ether, ethyl propyl ether, and polyethers;

esters such ethyl acetate, dimethyl adipate, propylene glycol monomethyl ether acetate, dimethyl glutarate, dimethyl succinate, glycerin acetate;

glycols such as ethylene glycols, diethylene glycol, polyethylene glycols, propylene glycols, dipropylene glycols, glycol ethers, glycol ether acetates;

carbonates such as propylene carbonate;

glycerols such as glycerin;

acetonitrile, tetrahydrofuran (THF), dimethyl formamide (DMF), N-methyl formamide (NMF), dimethyl sulfoxide (DMSO); and

mixtures thereof.

22. The composition of claim 20, wherein the second solvent is at least one dibasic ester.

23. The composition of claim 20, wherein the second solvent comprises a solvating agent or a wetting solvent.

24. The composition of claim 20, wherein the second solvent comprises:

dimethyl glutarate; and

dimethyl succinate;

wherein the ratio of dimethyl glutarate to dimethyl succinate is about two to one (2;

1).

25. The composition of claim 20, wherein the second solvent is present in an amount of about 0.1% to 10% by weight.

26. The composition of claim 20, wherein the second solvent is present in an amount of about 10% to 50% by weight.

27. The composition of claim 20, wherein the first solvent comprises N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, 1-octanol, ethanol, tetrahydrofurfuryl alcohol, or cyclohexanol, or mixtures thereof, and present in an amount of about 5% to 50% by weight;

wherein the viscosity modifier comprises methoxy propyl methylcellulose resin or hydroxy propyl methylcellulose resin or mixtures thereof, and present in an amount of about 0.10% to 5.0% by weight;

wherein the second solvent comprises N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, 1-octanol, ethanol, tetrahydrofurfuryl alcohol, or cyclohexanol, or mixtures thereof, and present in an amount of about 0.3% to 50% by weight.

28. The composition of claim 20, wherein the first solvent comprises N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, 1-octanol, ethanol, tetrahydrofurfuryl alcohol, or cyclohexanol, or mixtures thereof, and present in an amount of about 5% to 30% by weight;

wherein the viscosity modifier comprises methoxy propyl methylcellulose resin or hydroxy propyl methylcellulose resin or mixtures thereof, and present in an amount of about 1.0% to 3.0% by weight;

wherein the second solvent comprises N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, 1-octanol, ethanol, tetrahydrofurfuryl alcohol, or cyclohexanol, or mixtures thereof, and present in an amount of about 0.2% to 8.0% by weight; and

wherein the balance of the composition further comprises water.

29. The composition of claim 28, further comprising:

a plurality of substantially optically transparent and chemically inert particles having a range of sizes between about 10 to about 50 microns and present in an amount of about 0.1% to 2.5% by weight.

30. The composition of claim 20, wherein the first solvent comprises N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, 1-octanol, ethanol, tetrahydrofurfuryl alcohol, or cyclohexanol, or mixtures thereof, and present in an amount of about 40% to 60% by weight;

wherein the viscosity modifier comprises methoxy propyl methylcellulose resin or hydroxy propyl methylcellulose resin or mixtures thereof, and present in an amount of about 0.10% to 1.5% by weight;

wherein the second solvent comprises N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, 1-octanol, ethanol, tetrahydrofurfuryl alcohol, or cyclohexanol, or mixtures thereof, and present in an amount of about 40% to 60% by weight.

31. The composition of claim 30, further comprising:

a plurality of substantially optically transparent and chemically inert particles having a range of sizes between about 10 to about 50 microns and present in an amount of about 0.1% to 2.5% by weight.

32. A method of making the composition of claim 20, the method comprising:

mixing the plurality of diodes with the first solvent;

adding the mixture of the first solvent and plurality of diodes to the viscosity modifier;

adding the second solvent; and

mixing the plurality of diodes, the first solvent, the second solvent, and the viscosity modifier for about 25 to 30 minutes in an air atmosphere.

33. The method of claim 32, further comprising:

releasing the plurality of diodes from a wafer.

34. The method of claim 33, wherein the step of releasing the plurality of diodes from the wafer further comprises etching the back side of the wafer, grinding and polishing a back side of the wafer, or a laser lift-off from a back side of the wafer.

35. The composition of claim 20, wherein the first solvent comprises about 15% to 40% by weight of N-propanol, terpineol or diethylene glycol, ethanol, tetrahydrofurfuryl alcohol, or cyclohexanol, or mixtures thereof;

wherein the viscosity modifier comprises about 1.25% to 2.5% by weight of methoxy propyl methylcellulose resin or hydroxy propyl methylcellulose resin or mixtures thereof;

wherein the second solvent comprises about 0.5% to 10% by weight of a nonpolar resin solvent; and

wherein the balance of the composition further comprises water.

36. The composition of claim 20, wherein the first solvent comprises about 17.5% to 22.5% by weight of N-propanol, terpineol or diethylene glycol, ethanol, tetrahydrofurfuryl alcohol, or cyclohexanol, or mixtures thereof;

wherein the viscosity modifier comprises about 1.5% to 2.25% by weight of methoxy propyl methylcellulose resin or hydroxy propyl methylcellulose resin or mixtures thereof;

wherein the second solvent comprises about 0.01% to 6.0% by weight of at least one dibasic ester;

wherein the balance of the composition further comprises water; and

wherein the viscosity of the composition is substantially between about 5,000 cps to about 20,000 cps at 25°

C.

37. The composition of claim 20, wherein the first solvent comprises about 20% to 40% by weight of N-propanol, terpineol or diethylene glycol, ethanol, tetrahydrofurfuryl alcohol, or cyclohexanol, or mixtures thereof;

wherein the viscosity modifier comprises about 1.25% to 1.75% by weight of methoxy propyl methylcellulose resin or hydroxy propyl methylcellulose resin or mixtures thereof;

wherein the second solvent comprises about 0.01% to 6.0% by weight of at least one dibasic ester;

wherein the balance of the composition further comprises water; and

wherein the viscosity of the composition is substantially between about 1,000 cps to about 5,000 cps at 25°

C.

38. The composition of claim 1, wherein the composition has a viscosity substantially between about 100 cps and about 25,000 cps at about 25°

C.

39. The composition of claim 1, wherein the composition has a viscosity substantially between about 1,000 cps and about 10,000 cps at about 25°

C.

40. The composition of claim 1, wherein the composition has a viscosity substantially between about 10,000 cps and about 25,000 cps at about 25°

C.

41. The composition of claim 1, wherein each diode of the plurality of diodes comprises GaN and wherein the GaN portion of each diode of the plurality of diodes is substantially hexagonal, square, triangular, rectangular, lobed, stellate, or toroidal.

42. The diode of claim 1, wherein a light emitting or absorbing region of each diode of the plurality of diodes has a surface texture selected from the group consisting of:

a plurality of circular rings, a plurality of substantially curvilinear trapezoids, a plurality of parallel stripes, a stellate pattern, and mixtures thereof.

43. The composition of claim 1, wherein each diode of the plurality of diodes has a first metal terminal on a first side of the diode and a second metal terminal on a second, back side of the diode.

44. The composition of claim 43, wherein the first and second terminals are each between about 1 to 6 microns in height.

45. The composition of claim 1, wherein each diode of the plurality of diodes has a diameter between about 20 to 30 microns and a height between 5 to 15 microns, and each diode of the plurality of diodes has a plurality of first metal terminals on a first side and one second metal terminal on the first side, a contact of the second metal terminal spaced apart from contacts of the plurality of first metal terminals by about 2 to 5 microns in the height dimension.

46. The composition of claim 45, wherein each first metal terminal of the plurality of first metal terminals is between about 0.5 to 2 microns in height and the second metal terminal is between about 1 to 8 microns in height.

47. The composition of claim 1, wherein each diode of the plurality of diodes has a diameter between about 10 to 50 microns and a height between 5 to 25 microns, and each diode of the plurality of diodes has a plurality of first metal terminals on a first side and one second metal terminal on the first side, a contact of the second metal terminal spaced apart from contacts of the plurality of first metal terminals by about 1 to 7 microns in the height dimension.

48. The composition of claim 1, wherein each diode of the plurality of diodes has at least one metal via structure extending between at least one p+ or n+ GaN layer on a first side of the diode to a second, back side of the diode.

49. The composition of claim 48, wherein the metal via structure comprises a central via, a peripheral via, or a perimeter via.

50. The composition of claim 1, wherein each diode of the plurality of diodes is less than about 30 microns in any dimension.

51. The composition of claim 1, wherein each diode of the plurality of diodes is substantially hexagonal, is about 20 to 30 microns in diameter measured opposing face-to-face, and is about 5 to 15 microns in height.

52. The composition of claim 1, wherein the lateral sides of each diode of the plurality of diodes are less than about 10 microns in height.

53. The composition of claim 1, wherein the lateral sides of each diode of the plurality of diodes are between about 2.5 to 6 microns in height.

54. The composition of claim 1, wherein the lateral sides of each diode of the plurality of diodes are substantially sigmoidal and terminate in a curved point.

55. The composition of claim 1, wherein the viscosity modifier further comprises an adhesive viscosity modifier.

56. The composition of claim 1, wherein the viscosity modifier, when dried or cured, forms a polymer or resin lattice or structure substantially about the periphery of each diode of the plurality of diodes.

57. The composition of claim 1, wherein the composition is visually opaque when wet and substantially optically clear when dried or cured.

58. The composition of claim 1, wherein the composition has a contact angle greater than about 25 degrees or greater than about 40 degrees.

59. The composition of claim 1, wherein each diode of the plurality of diodes comprises at least one inorganic semiconductor selected from the group consisting of:

silicon, gallium arsenide (GaAs), gallium nitride (GaN), GaP, InAlGaP, InAlGaP, AlInGaAs, InGaNAs, and AlInGASb.

60. The composition of claim 1, wherein each diode of the plurality of diodes comprises at least one organic semiconductor selected from the group consisting of:

π

-conjugated polymers, poly(acetylene)s, poly(pyrrole)s, poly(thiophene)s, polyanilines, polythiophenes, poly(p-phenylene sulfide), poly(para-phenylene vinylene)s (PPV) and PPV derivatives, poly(3-alkylthiophenes), polyindole, polypyrene, polycarbazole, polyazulene, polyazepine, poly(fluorene)s, polynaphthalene, polyaniline, polyaniline derivatives, polythiophene, polythiophene derivatives, polypyrrole, polypyrrole derivatives, polythianaphthene, polythianaphthane derivatives, polyparaphenylene, polyparaphenylene derivatives, polyacetylene, polyacetylene derivatives, polydiacethylene, polydiacetylene derivatives, polyparaphenylenevinylene, polyparaphenylenevinylene derivatives, polynaphthalene, polynaphthalene derivatives, polyisothianaphthene (PITN), polyheteroarylenvinylene (ParV) in which the heteroarylene group is thiophene, furan or pyrrol, polyphenylene-sulphide (PPS), polyperinaphthalene (PPN), polyphthalocyanine (PPhc), and their derivatives, copolymers thereof and mixtures thereof.

61. The composition of claim 1, wherein the composition has a relative evaporation rate less than one, wherein the evaporation rate is relative to butyl acetate having a rate of one.

62. A method of using the composition of claim 1, the method comprising:

printing the composition over a base or over a first conductor coupled to the base.

63. A composition comprising:

a plurality of diodes;

a first solvent; and

a viscosity modifier;

wherein the composition has a viscosity substantially about 100 cps to about 25,000 cps at about 25°

C.

64. The composition of claim 63, wherein the first solvent comprises at least one solvent selected from the group consisting of:

water;

alcohols such as methanol, ethanol, N-propanol (including 1-propanol, 2-propanol (isopropanol), 1-methoxy-2-propanol), butanol (including 1-butanol, 2-butanol (isobutanol), pentanol (including 1-pentanol, 2-pentanol, 3-pentanol), octanol, N-octanol (including 1-octanol, 2-octanol, 3-octanol), tetrahydrofurfuryl alcohol, cyclohexanol, terpineol;

ethers such as methyl ethyl ether, diethyl ether, ethyl propyl ether, and polyethers;

esters such ethyl acetate, dimethyl adipate, propylene glycol monomethyl ether acetate, dimethyl glutarate, dimethyl succinate, glycerin acetate;

glycols such as ethylene glycols, diethylene glycol, polyethylene glycols, propylene glycols, dipropylene glycols, glycol ethers, glycol ether acetates;

carbonates such as propylene carbonate;

glycerols such as glycerin;

acetonitrile, tetrahydrofuran (THF), dimethyl formamide (DMF), N-methyl formamide (NMF), dimethyl sulfoxide (DMSO); and

mixtures thereof.

65. The composition of claim 63, wherein each diode of the plurality of diodes has a diameter between about 10 to 50 microns and a height between about 5 to 25 microns.

66. The composition of claim 63, wherein each diode of the plurality of diodes has a width and length each between about 10 to 50 microns and a height between about 5 to 25 microns.

67. The composition of claim 63, further comprising:

a plurality of substantially optically transparent and chemically inert particles having a range of sizes between about 10 to about 50 microns and present in an amount of about 0.1% to 2.5% by weight.

68. The composition of claim 63, wherein the first solvent is present in an amount of about 0.3% to 50% by weight.

69. The composition of claim 63, wherein the viscosity modifier comprises a methoxy propyl methylcellulose resin or a hydroxy propyl methylcellulose resin or a mixture thereof.

70. The composition of claim 63, wherein the viscosity modifier is present in an amount of about 0.30% to 5% by weight.

71. The composition of claim 63, wherein the viscosity modifier is present in an amount of about 0.10% to 3% by weight.

72. The composition of claim 63, wherein the viscosity modifier comprises at least one viscosity modifier selected from the group consisting of:

clays such as hectorite clays, garamite clays, organo-modified clays;

saccharides and polysaccharides such as guar gum, xanthan gum;

celluloses and modified celluloses such as hydroxy methylcellulose, methylcellulose, ethyl cellulose, propyl methylcellulose, methoxy cellulose, methoxy methylcellulose, methoxy propyl methylcellulose, hydroxy propyl methylcellulose, carboxy methylcellulose, hydroxy ethylcellulose, ethyl hydroxyl ethylcellulose, cellulose ether, cellulose ethyl ether, chitosan;

polymers such as acrylate and (meth)acrylate polymers and copolymers;

glycols such as ethylene glycols, diethylene glycol, polyethylene glycols, propylene glycols, dipropylene glycols, glycol ethers, glycol ether acetates;

fumed silica, silica powders;

modified ureas; and

mixtures thereof.

73. The composition of claim 63, further comprising a second solvent different from the first solvent.

74. The composition of claim 73, wherein the second solvent is at least one solvent selected from the group consisting of:

water;

alcohols such as methanol, ethanol, N-propanol (including 1-propanol, 2-propanol (isopropanol), 1-methoxy-2-propanol), butanol (including 1-butanol, 2-butanol (isobutanol), pentanol (including 1-pentanol, 2-pentanol, 3-pentanol), octanol, N-octanol (including 1-octanol, 2-octanol, 3-octanol), tetrahydrofurfuryl alcohol, cyclohexanol, terpineol;

ethers such as methyl ethyl ether, diethyl ether, ethyl propyl ether, and polyethers;

esters such ethyl acetate, dimethyl adipate, propylene glycol monomethyl ether acetate, dimethyl glutarate, dimethyl succinate, glycerin acetate;

glycols such as ethylene glycols, diethylene glycol, polyethylene glycols, propylene glycols, dipropylene glycols, glycol ethers, glycol ether acetates;

carbonates such as propylene carbonate;

glycerols such as glycerin;

acetonitrile, tetrahydrofuran (THF), dimethyl formamide (DMF), N-methyl formamide (NMF), dimethyl sulfoxide (DMSO); and

mixtures thereof.

75. The composition of claim 73, wherein the second solvent is at least one dibasic ester.

76. The composition of claim 73, wherein the second solvent is present in an amount of about 0.1% to 50% by weight.

77. The composition of claim 73, wherein the first solvent comprises N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, 1-octanol, ethanol, tetrahydrofurfuryl alcohol, or cyclohexanol, or mixtures thereof, and present in an amount of about 5% to 60% by weight;

wherein the viscosity modifier comprises methoxy propyl methylcellulose resin or hydroxy propyl methylcellulose resin or mixtures thereof, and present in an amount of about 0.10% to 5.0% by weight;

wherein the second solvent comprises N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, 1-octanol, ethanol, tetrahydrofurfuryl alcohol, or cyclohexanol, or mixtures thereof, and present in an amount of about 0.3% to 60% by weight.

78. The composition of claim 77, further comprising:

a plurality of substantially optically transparent and chemically inert particles having a range of sizes between about 10 to about 50 microns and present in an amount of about 0.1% to 2.5% by weight.

79. The composition of claim 63, wherein the composition has a viscosity substantially between about 1,000 cps and about 10,000 cps at about 25°

C.

80. The composition of claim 63, wherein the composition has a viscosity substantially between about 10,000 cps and about 25,000 cps at about 25°

C.

81. The composition of claim 63, wherein each diode of the plurality of diodes has a first metal terminal on a first side of the diode and a second metal terminal on a second, back side of the diode.

82. The composition of claim 81, wherein the first and second terminals are each between about 1 to 6 microns in height.

83. The composition of claim 63, wherein each diode of the plurality of diodes has a diameter between about 20 to 30 microns and a height between 5 to 15 microns, and each diode of the plurality of diodes has a plurality of first metal terminals on a first side and one second metal terminal on the first side, a contact of the second metal terminal spaced apart from contacts of the plurality of first metal terminals by about 2 to 5 microns in the height dimension.

84. The composition of claim 83, wherein each first metal terminal of the plurality of first metal terminals is between about 0.5 to 2 microns in height and the second metal terminal is between about 1 to 8 microns in height.

85. The composition of claim 63, wherein each diode of the plurality of diodes has a diameter between about 10 to 50 microns and a height between 5 to 25 microns, and each diode of the plurality of diodes has a plurality of first metal terminals on a first side and one second metal terminal on the first side, a contact of the second metal terminal spaced apart from contacts of the plurality of first metal terminals by about 1 to 7 microns in the height dimension.

86. The composition of claim 63, wherein each diode of the plurality of diodes is less than about 50 microns in any dimension.

87. The composition of claim 63, wherein each diode of the plurality of diodes is substantially hexagonal, is about 20 to 30 microns in diameter measured opposing face-to-face, and is about 5 to 15 microns in height.

88. The composition of claim 63, wherein the lateral sides of each diode of the plurality of diodes are less than about 10 microns in height.

89. The composition of claim 63, wherein the lateral sides of each diode of the plurality of diodes are substantially sigmoidal and terminate in a curved point.

90. The composition of claim 63, wherein the plurality of diodes are light emitting diodes or photovoltaic diodes.

91. A composition comprising:

a plurality of diodes, each diode of the plurality of diodes less than about 50 microns in any dimension;

a first solvent;

a second solvent different from the first solvent; and

a viscosity modifier;

wherein the composition has a viscosity substantially about 50 cps to about 25,000 cps at about 25°

C.

92. The composition of claim 91, wherein the first solvent comprises at least one solvent selected from the group consisting of:

water;

alcohols such as methanol, ethanol, N-propanol (including 1-propanol, 2-propanol (isopropanol), 1-methoxy-2-propanol), butanol (including 1-butanol, 2-butanol (isobutanol), pentanol (including 1-pentanol, 2-pentanol, 3-pentanol), octanol, N-octanol (including 1-octanol, 2-octanol, 3-octanol), tetrahydrofurfuryl alcohol, cyclohexanol, terpineol;

ethers such as methyl ethyl ether, diethyl ether, ethyl propyl ether, and polyethers;

esters such ethyl acetate, dimethyl adipate, propylene glycol monomethyl ether acetate, dimethyl glutarate, dimethyl succinate, glycerin acetate;

glycols such as ethylene glycols, diethylene glycol, polyethylene glycols, propylene glycols, dipropylene glycols, glycol ethers, glycol ether acetates;

carbonates such as propylene carbonate;

glycerols such as glycerin;

acetonitrile, tetrahydrofuran (THF), dimethyl formamide (DMF), N-methyl formamide (NMF), dimethyl sulfoxide (DMSO); and

mixtures thereof.

93. The composition of claim 91, wherein each diode of the plurality of diodes has a diameter between about 10 to 50 microns and a height between about 5 to 25 microns.

94. The composition of claim 91, wherein each diode of the plurality of diodes has a width and length each between about 10 to 50 microns and a height between about 5 to 25 microns.

95. The composition of claim 91, further comprising:

a plurality of substantially optically transparent and chemically inert particles having a range of sizes between about 10 to about 50 microns and present in an amount of about 0.1% to 2.5% by weight.

96. The composition of claim 91, wherein the first solvent is present in an amount of about 0.3% to 60% by weight and the second solvent is present in an amount of about 0.3% to 60% by weight.

97. The composition of claim 91, wherein the viscosity modifier comprises a methoxy propyl methylcellulose resin or a hydroxy propyl methylcellulose resin or a mixture thereof, and wherein the viscosity modifier is present in an amount of about 0.10% to 5% by weight.

98. The composition of claim 91, wherein the viscosity modifier comprises at least one viscosity modifier selected from the group consisting of:

clays such as hectorite clays, garamite clays, organo-modified clays;

saccharides and polysaccharides such as guar gum, xanthan gum;

celluloses and modified celluloses such as hydroxy methylcellulose, methylcellulose, ethyl cellulose, propyl methylcellulose, methoxy cellulose, methoxy methylcellulose, methoxy propyl methylcellulose, hydroxy propyl methylcellulose, carboxy methylcellulose, hydroxy ethylcellulose, ethyl hydroxyl ethylcellulose, cellulose ether, cellulose ethyl ether, chitosan;

polymers such as acrylate and (meth)acrylate polymers and copolymers;

glycols such as ethylene glycols, diethylene glycol, polyethylene glycols, propylene glycols, dipropylene glycols, glycol ethers, glycol ether acetates;

fumed silica, silica powders;

modified ureas; and

mixtures thereof.

99. The composition of claim 91, wherein the second solvent is at least one solvent selected from the group consisting of:

water;

alcohols such as methanol, ethanol, N-propanol (including 1-propanol, 2-propanol (isopropanol), 1-methoxy-2-propanol), butanol (including 1-butanol, 2-butanol (isobutanol), pentanol (including 1-pentanol, 2-pentanol, 3-pentanol), octanol, N-octanol (including 1-octanol, 2-octanol, 3-octanol), tetrahydrofurfuryl alcohol, cyclohexanol, terpineol;

ethers such as methyl ethyl ether, diethyl ether, ethyl propyl ether, and polyethers;

esters such ethyl acetate, dimethyl adipate, propylene glycol monomethyl ether acetate, dimethyl glutarate, dimethyl succinate, glycerin acetate;

glycols such as ethylene glycols, diethylene glycol, polyethylene glycols, propylene glycols, dipropylene glycols, glycol ethers, glycol ether acetates;

carbonates such as propylene carbonate;

glycerols such as glycerin;

acetonitrile, tetrahydrofuran (THF), dimethyl formamide (DMF), N-methyl formamide (NMF), dimethyl sulfoxide (DMSO); and

mixtures thereof.

100. The composition of claim 91, wherein the first solvent comprises N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, 1-octanol, ethanol, tetrahydrofurfuryl alcohol, or cyclohexanol, or mixtures thereof, and present in an amount of about 5% to 60% by weight;

wherein the viscosity modifier comprises methoxy propyl methylcellulose resin or hydroxy propyl methylcellulose resin or mixtures thereof, and present in an amount of about 0.10% to 5.0% by weight;

wherein the second solvent comprises N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, 1-octanol, ethanol, tetrahydrofurfuryl alcohol, or cyclohexanol, or mixtures thereof, and present in an amount of about 0.3% to 60% by weight.

101. The composition of claim 91, wherein the lateral sides of each diode of the plurality of diodes are less than about 10 microns in height, are substantially sigmoidal and terminate in a curved point.

102. The composition of claim 91, wherein the plurality of diodes are light emitting diodes or photovoltaic diodes.

103. A composition comprising:

a plurality of diodes less than about 50 microns in any dimension; and

a viscosity modifier to provide a viscosity of the composition substantially between about 100 cps and about 20,000 cps at about 25°

C.

104. A composition comprising:

a plurality of diodes;

a first solvent selected from the group consisting of;

N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, 1-octanol, ethanol, tetrahydrofurfuryl alcohol, cyclohexanol, and mixtures thereof;

a viscosity modifier selected from the group consisting of;

methoxy propyl methylcellulose resin, hydroxy propyl methylcellulose resin, and mixtures thereof; and

a second solvent different from the first solvent, the second solvent selected from the group consisting of;

N-propanol, isopropanol, dipropylene glycol, diethylene glycol, propylene glycol, 1-methoxy-2-propanol, 1-octanol, ethanol, tetrahydrofurfuryl alcohol, cyclohexanol, and mixtures thereof.