KR101165484B1 - A method of delivering ink to a substrate surface, a method of writing conductive metal, an ink formulation for nanolithography or microlithography, a method for depositing metallic traces, a method and device for repair of a flat panel display substrate - Google Patents

Abstract

A new low temperature method for directly writing conductive metal traces with micron and submicron sized features is disclosed. In this method, a flat beam, such as an AFM cantilever, with or without a tip is used to draw traces of metal precursor ink on a substrate. The dimensions of the metal traces can be controlled directly by the structure of the cantilever, and thus microcontrolled cantilevers can be used to controllably deposit traces from 1 micron to 100 microns wide. The cantilever with a sharp tip can be used to further reduce the minimum feature size to the submicron scale. The height of the feature can be increased by forming layers of similar or different materials. In order to obtain a highly conductive and robust pattern using this deposition method, two general ink formulation strategies have been designed. The main components of both ink systems are nanoparticles with a diameter of less than 100 nm. Nanoparticles generally have significantly lower melting points than bulk materials, so they can melt, sinter or coalesce a collection of individual particles into a continuous (poly) crystalline film at very low temperatures (below about 300 ° C, about 120 ° C). have. In a first strategy, hydrocarbon-capped nanoparticles can be dispersed in a suitable solvent and deposited on the surface in the form of a pattern, followed by annealing the film using heat to form a continuous metal pattern. In a second strategy, the metal compound can be delivered to the surface in the presence of a reducing matrix and then thermally formed nanoparticles in situ and then coalesced to form a continuous metal pattern. In studies with platinum and gold inks, both nanoparticle based methods form micron-sized traces on glass and silicon oxide with low resistivity (μΩcm) and good adhesion.

Description

A method of delivering ink to a substrate surface, a method of writing a conductive metal, an ink formulation for nanolithography or microlithography, a method for depositing a metal trace, a method for repairing a flat panel display substrate, and an apparatus SUBSTRATE SURFACE, A METHOD OF WRITING CONDUCTIVE METAL, AN INK FORMULATION FOR NANOLITHOGRAPHY OR MICROLITHOGRAPHY, A METHOD FOR DEPOSITING METALLIC TRACES, A METHOD AND DEVICE FOR REPAIR OF A FLAT PANEL DISPLAY SUBSTRATE}

This application claims the benefit of US Provisional Application No. 60 / 547,091 filed on February 25, 2004, which is incorporated by reference in its entirety (Agent No. 083847-0234). This application also discloses U.S. Provisional Application No. 10 / 647,430, filed Aug. 26, 2003, which claims priority to U.S. Provisional Application No. 60 / 405,741, filed Aug. 26, 2002 (Agent No. 083847-0150). Some serial applications of agent number 083847-0200).

The present invention relates generally to (i) micron-scale direct write patterning methods using microfabricated (tipless) cantilevers, which may be referred to as cantilever microdeposition, and (ii) the flatness of this method. The present invention relates to repair of a display device, in particular for repair of a TFT LCD (thin film transistor liquid crystal display device).

In many current and recent technical fields, there is a strong commercial need for direct writing techniques that can deposit materials, particularly metals and semiconductors, in patterns with micron and submicron sized features (ie, structures). Although most microelectronic devices are fabricated through photolithography, the need for direct write technology is particularly evident in the area of additive defect repair and circuit editing. For example, damaged or defective photomasks inflict a great deal of damage and waste on the microelectronics industry due to the lack of suitable tools for the addition and repair of missing materials on nanoscale features. At the micron length scale, damage to the metal components of the array of thin film transistors (TFTs) in the flat panel display (FPD) is difficult to repair due to the lack of a high speed and low cost method for depositing micron sized conductive traces. Photolithography can be performed to fabricate the device, but this requires complex and expensive instruments that enormously cost the technology for low volume, high performance components or prototyping applications. In this case, other techniques, such as a direct write process, can provide significant advantages and capabilities. Inkjet printing, the most common direct writing technique, provides a convenient and flexible method for printing different materials ranging from biological molecules to materials for microelectronics. However, the resolution of this technique is generally limited to dots of size 15-200 microns, which is not sufficient for many applications (see, for example, US Patent Application 2004/0261700 to Edwards et al.). Other direct writing tools, such as laser assisted deposition, electron or ion beam lithography, experience similar resolution limitations, are too expensive for many applications, or can be used to directly manufacture or repair active and passive microelectronics or optoelectronic components. Has material limitations that hinder their use. In particular, electron beam lithography, ion beam micromachining, laser or electron beam assisted chemical vapor deposition require enormously expensive (partial) vacuums for very large plates (eg, wide TV or computer screens).

The invention is further illustrated using a non-limiting summary. New contact methods have been developed for writing conductive metal features that provide controllable feature sizes of submicron dimensions at 100 microns. In this method, the (microfabricated) cantilever can be loaded with, for example, molecular or nanoparticle inks, which are dispensed in very small amounts, for example in the form of line and dot patterns, by contacting the surface. In the present form, loading and deposition of cantilevers can be performed manually. However, additional systems can include active ink delivery by increasing the complexity of the microfabrication cantilever. In addition, a number of metal precursor ink systems have been developed that are compatible with this method, so that patterning can be performed using a number of different metal and metal oxide materials. Importantly, precursor inks can be patterned under atmospheric environmental conditions and converted to metal films at relatively low temperatures, so that they can be applied to substrates such as plastics, for example, that cannot withstand high temperature processes.

In a preferred embodiment, the present invention provides a method for writing a conductive metal or metal precursor, for example, which method can be a tipless cantilever and providing a cantilever having a cantilever end; Providing ink disposed at the cantilever end; Providing a substrate surface; And moving the cantilever end or moving the substrate surface such that ink is transferred from the cantilever to the substrate surface. The substrate surface may move, the cantilever may stop, or the substrate surface may stop, and the cantilever may move. The movement that causes ink delivery generally results in contact of the substrate surface with the cantilever, which may be ink between the cantilever and the surface.

In another preferred embodiment, the present invention provides a method for writing a conductive metal or metal precursor, which method comprises two or more cantilevers, each having a cantilever end, which can include a tip at the end or a tipless cantilever; Providing a gap between about 1 micron and about 20 microns between them; Providing an ink disposed within the gap; Providing a substrate surface; Contacting the substrate surface with two or more cantilevers having a gap such that ink is delivered from the gap to the substrate surface.

The invention also provides an ink formulation for microlithography or nanolithography, the composition comprising at least one metal salt and at least one solvent, wherein the concentration of the metal salt is from about 1 mg / 100 μL to about 500 mg / 100 μL. The amount of metal salt can be adjusted sufficiently large to provide adequate dispersion and proper mass density and thickness for a given application.

The present invention also provides a method for directly writing a conductive metal, the method comprising providing a cantilever, which can be a tipless cantilever having a cantilever end; Providing an ink comprising metal nanoparticles disposed at the cantilever end; Providing a substrate surface; Contacting the cantilever with the substrate surface such that ink is transferred from the cantilever to the substrate surface.

Important advantages of the present invention include, for example, in the range of about 1 micron to about 15 microns or in the range of about 1 micron to about 10 microns (eg, a single number) for lateral dimensions such as length and width with good control. It provides the ability to operate in various different size ranges for a particular system. In many embodiments, the problem of clogging the nozzle or pipette can be avoided. The mechanism for doing this is relatively simple and does not require high vacuum, for example. Matching and multifunctionality are also excellent. Mass production and single use are also available.

In addition, serialized embodiments are provided:

1. A method of depositing a conductive coating of a desired pattern on a substrate, comprising: depositing the precursor in a desired pattern on the substrate by nanolithography using a precursor coated tip; Contacting the precursor with a ligand; Applying sufficient energy to move electrons from the ligand to the precursor to decompose the precursor to form a conductive precipitate of a desired pattern, thus forming a conductive pattern directly on the substrate.

2. The method of 1 wherein the tip is a nano tip.

3. The method of 1, wherein the tip is a scanning probe micro tip.

4. The method of 1, wherein the tip is a nuclear micro tip.

5. The method of 1 wherein the coating comprises a metal having a purity of at least about 80%.

6. The method of 1 wherein the coating comprises a metal having a thickness of less than about 10 angstroms.

7. The method of 1 wherein the coating comprises a metal having a thickness of at least about 100 Angstroms.

8. The method of 1 wherein said precursor comprises a salt selected from the group consisting of carboxylates, halides, pseudo halides and nitrates.

9. The method of 1 wherein said precursor comprises a carboxylate.

10. The method of 1, wherein the pattern comprises a circuit.

11. The method of 1 wherein said ligand comprises a material selected from the group consisting of amines, amides, phosphorus hydrides, sulfides and esters.

12. The method of 1, wherein the ligand is selected from the group consisting of nitrogen donors, sulfur donors and phosphorus donors.

13. The method of 1, wherein the precipitate comprises a metal.

14. The process according to 1, wherein the precipitate is selected from the group consisting of copper, zinc, palladium, platinum, silver, gold, cadmium, titanium, cobalt, lead, tin, silicon and germanium.

15. The method of 1, wherein the precipitate comprises a conductor.

16. The method of 1, wherein the precipitate comprises a semiconductor.

17. The method of 1 wherein the substrate comprises an insulator.

18. The method of 1 wherein the substrate comprises at least one of a conductor and a semiconductor.

19. The method of 1, wherein applying energy comprises applying heat.

20. The method of 1, wherein applying energy comprises applying infrared light or UV light.

21. The method of 1, wherein applying the energy comprises applying vibrational energy.

22. The material of 1, wherein the precursor comprises a salt selected from the group consisting of carboxylates, halides, pseudo halides, nitrates, and the ligand is a material selected from the group consisting of amines, amides, hydrides, sulfides and esters How to include.

23. The process according to 19, wherein the precipitate is selected from the group consisting of copper, zinc, palladium, platinum, silver, gold, cadmium, titanium, cobalt, lead, tin, silicon and germanium.

24. The method of 19, wherein applying energy comprises applying radiant heat.

25. A method of printing a conductive metal on a substrate in a desired pattern,

Drawing metal precursors and ligands directly onto the substrate according to a desired pattern using nanolithography using a tip coated with a precursor; And

Forming a conductive metal in the desired pattern by applying energy to decompose the precursor without removing a substantial amount of the precursor from the substrate and without removing a substantial amount of the metal from the substrate.

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26. The method of 25, wherein the metal pattern comprises a substantially pure metal having less than about 20 weight percent impurities.

27. The method of 25, wherein said cracking step comprises thermal cracking.

28. The method of 25, wherein said cracking comprises thermal cracking at a temperature of less than about 300 ° C.

29. The method of 25, wherein the metal is selected from the group consisting of elemental metals, alloys, metal / metal composites, metal ceramic composites and metal polymer composites.

30. A method of nanolithography comprising depositing a metal precursor on a substrate from a tip to form a nanostructure, and then converting the precursor nanostructure to a metal deposit.

31. The method of 30, wherein the deposition and conversion are performed without using an electrical bias between the tip and the substrate.

32. The method of 30, wherein said deposition and conversion are performed using a chemical rather than a substrate.

33. The method of 30, wherein the tip is a nanoclass tip.

34. The method of 30, wherein the tip is a scanning probe micro tip.

35. The method of 30, wherein the tip is an AFM tip.

36. The method of 35, wherein the deposition and conversion is performed without using an electrical bias between the tip and the substrate.

37. The method of 30, wherein the method is repeated to form a multilayer.

38. The method of 30, wherein the tip is not suitable for reacting with the precursor.

39. The method of 30, wherein the method is used to connect at least one nanowire to another structure.

40. The method of 30, wherein the method is used to connect at least two electrodes.

41. The method of 30, wherein the method is used to prepare a sensor.

42. The method of 30, wherein the method is used to produce a lithography template.

43. The method of 30, wherein the method is used to prepare a biosensor.

44. Nanolithography as a prerequisite for depositing an ink composite with a metal precursor as an essential component on a substrate from a nanoscale tip to form a nanostructure, and then converting the nanostructured metal precursor into a metal form Way.

45. The method of 44, wherein the transformation is a thermal transformation without the use of chemicals.

46. The method of 44, wherein said transformation is a chemical transformation carried out using a reducing agent.

47. The method of 44, wherein the reducing agent is used in the vapor state to effect the conversion.

48. The method of 44, wherein the tip is an AFM tip

49. The method of 44, wherein the tip comprises a surface that does not react with the precursor.

50. The method of 44, wherein the method is repeated a plurality of times to form a multilayer structure.

51. A method of printing without using an electrochemical bias or reaction between an ink and a substrate, wherein a metal precursor ink composite is deposited from the tip onto the substrate in the form of microstructures or nanostructures on the substrate to each other up to about 1 micron or less. Forming an array with separated discrete objects.

52. The method of 51, further comprising forming a metal from the precursor.

53. The method of 51, wherein the discrete objects are separated from each other by about 500 nm or less.

54. The method of 51, wherein the discrete objects are separated from each other by about 10 nm or less.

55. A method of writing a conductive metal,

Providing a cantilever having a cantilever end, the cantilever may include a tip at the end or may be a tipless cantilever;

Providing ink disposed at the cantilever end;

Providing a substrate surface;

Contacting the cantilever end with the substrate surface such that the ink is transferred from the cantilever end to the substrate surface

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56. The method of 55, wherein the substrate surface is moved and the cantilever is stopped.

57. The method of 55, wherein the substrate surface is stationary and the cantilever is moved.

58. The method of 55, wherein the cantilever is a tipless cantilever.

59. The method of 55, wherein the cantilever includes a tip at the cantilever end.

60. The method of 55, wherein the ink comprises one or more metals.

61. The method of 55, wherein the ink comprises one or more metal salts.

62. The method of 55, wherein the ink comprises one or more metal nanoparticles.

63. The method of 55, wherein the ink comprises one or more hydrophobic nanoparticles.

64. The method of 55, wherein the ink comprises one or more hydrophilic nanoparticles.

65. The method of 55, wherein the ink comprises one or more metal nanoparticles having an organic shell.

66. The method of 55, wherein the ink comprises one or more metal nanoparticles having an insulating shell.

67. The method of 55, wherein the ink is a hydrophobic ink.

68. The method of 55, wherein the ink is a hydrophilic ink.

69. The method of 55, wherein the ink is a hydrophobic ink and the substrate surface is a hydrophobic surface.

70. The method of 55, wherein the ink is a hydrophilic ink and the substrate surface is a hydrophilic surface.

71. The method of 55, wherein the ink comprises both hydrophobic and hydrophilic agents.

72. The method of 55, wherein the ink comprises one or more metal nanoparticles having an average diameter of about 100 nm or less.

73. The method of 55, wherein the ink comprises one or more biological molecules.

74. The method of 55, wherein the ink comprises one or more peptides or proteins.

75. The method of 55, wherein the ink comprises one or more nucleic acids.

76. The method of 55, wherein the ink comprises one or more sol-gel materials.

77. The method of 55, wherein the ink comprises one or more magnetic materials or precursors thereof.

78. The method of 55, wherein the ink comprises one or more semiconductor materials or precursors thereof.

79. The method of 55, wherein the ink comprises one or more optical materials or precursors thereof.

80. The method of 55, wherein the ink comprises one or more solvents having a boiling point above 100 ° C.

81. The method of 55, wherein the ink comprises one or more compounds that are chemisorbed or covalently bonded to the substrate surface.

82. The method of 55, wherein the ink forms a feature on the substrate surface.

83. The method of 55, wherein the ink forms a metal oxide on the surface.

84. The method of 55, wherein the ink forms a metal alloy on the surface.

85. The method of 55, wherein the ink forms a feature on the substrate surface having dimensions controlled by the geometry of the cantilever.

86. The method of 55, wherein the ink forms a feature having a width of about 1 micron to about 100 microns on the substrate surface.

87. The method of 55, wherein the ink forms a feature on the substrate surface and the feature is exposed to melting, sintering or coalescing conditions.

88. The method of 55, wherein the ink forms a feature on the substrate surface and the feature is annealed.

89. The method of 55, wherein the ink forms a feature on the substrate surface and the feature is exposed to light.

90. The method of 55, wherein the ink forms a feature on the substrate surface and the feature is exposed to a laser.

91. The method of 55, wherein the ink forms a feature on the substrate surface and the feature is exposed to a current.

92. The method of 55, wherein the ink forms a feature on the substrate surface that contacts one or more electrodes on the substrate surface.

93. The method of 55, wherein the ink forms a feature on the substrate surface and is annealed at a temperature of about 300 ° C. or less.

94. The method of 55, wherein the ink forms a feature on the substrate surface and is annealed at a temperature of about 100 ° C to about 300 ° C.

95. The method of 55, wherein the ink is exposed to a reduction reaction on the substrate surface.

96. The method of 55, wherein the ink is continuous on contact with the substrate surface.

97. The method of claim 55, wherein the ink converts to a metallic state having a resistivity of about 10 μΩcm on the substrate surface.

98. The method of claim 55, wherein the ink is converted to a metallic state having a resistivity of about 1 μΩcm to about 10 μΩcm on the substrate surface.

99. The method of 55, wherein the ink forms a feature having a width of about 5 nm to about 1 micron on the substrate surface.

100. The method of 55, wherein the method is repeated to form layers of ink on the substrate surface.

101. The method of 55, wherein the method is repeated to form layers of ink on the substrate surface, wherein the inks are the same material.

102. The method of 55, wherein the method is repeated to form layers of ink on the substrate surface, wherein the inks are different materials.

103. The method of 55, wherein the ink is a line on the substrate surface.

104. The method of 55, wherein the ink is a dot on the substrate surface.

105. The method of 55, wherein the cantilever is an AFM cantilever.

106. The method of 55, wherein the substrate surface is glass.

107. The method of 55, wherein the substrate surface is a thin film transistor array.

108. The method of 55, wherein the method is used to repair a flat panel display.

109. The method of 55, wherein the cantilever is loaded with ink using a microfabricated ink bottle filled with ink.

110. The method of 55, wherein the cantilever contacts the substrate surface at an angle of about 10 degrees or less.

111. The method of 55, wherein the cantilever is in contact with the substrate surface at an angle of about 5 degrees or less.

112. The method of 55, wherein the cantilever is baked on contact when viewed by an optical microscope.

113. The method of 55, wherein the contacting is performed using force feedback.

114. The method of 55, wherein the contacting is performed using a piezoelectric scanning function.

115. The method of 55, wherein the cantilever has a width of about 1 micron to about 100 microns.

116. The method of 55, wherein the cantilever has a width of about 5 microns to about 25 microns.

117. The method of 55, wherein the cantilever is a straight beam shaped cantilever.

118. The method of 55, wherein the contacting is performed using force feedback.

119. The method of 55, wherein the cantilever has a spring constant of about 0.001 N / m to about 0.50 N / m.

120. The method of 55, wherein the cantilever has a spring constant of about 0.004 N / m to about 0.20 N / m.

121. The method of 55, wherein the cantilever has a length of about 100 microns to 400 microns.

122. The method of 55, wherein the cantilever has a length of about 150 microns to about 300 microns.

123. The method of 55, wherein the cantilever is one of a plurality of cantilevers that deposit ink in parallel.

124. The method of 55, wherein the ink is a polyol ink.

125. The method of 55, wherein the ink comprises a metal salt with one or more alcohols or polyols.

126. The method of 55, wherein the ink forms a feature having a lateral dimension on the substrate surface of about 1 micron to about 15 microns.

127. The method of 55, wherein the ink forms a feature having a lateral dimension on the substrate surface of about 1 micron to about 10 microns.

128. The method of 55, wherein the ink forms a feature having a lateral dimension on the substrate surface of about 1 micron to about 15 microns.

129. A substrate comprising a substrate surface and an ink prepared by the method of clause 55.

130. A method of writing a conductive metal,

Providing at least two cantilevers, each having a cantilever end, wherein the cantilevers may include a tip or a tipless cantilever at the end, the cantilevers having a gap between them of about 1 micron to about 20 microns;

Providing ink disposed within the gap;

Providing a substrate surface;

Contacting the substrate surface with at least two cantilevers having the gap such that the ink is transferred from the gap to the substrate surface.

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131. The method of 130, wherein the gap is from about 1 micron to about 5 microns.

132. The method of 130, wherein the gap is from about 5 microns to about 10 microns.

133. The method of 130, wherein the gap is from about 10 microns to about 20 microns.

134. Ink formulation for nanolithography, comprising at least one metal salt and at least one solvent, wherein the concentration of the metal salt is from about 1 mg / 100 μL to about 500 mg / 100 μL.

135. The ink formulation of 134, wherein the concentration of the metal salt is from about 1 mg / 100 μL to about 200 mg / 100 μL.

136. The ink formulation of 134, wherein the concentration of the metal salt is from about 5 mg / 100 μL to about 30 mg / 100 μL.

137. The ink formulation of 134, wherein the composition further comprises two or more oligomers or polymers having different average molecular weights.

138. The ink formulation of 134, wherein the composition further comprises at least one oligomer and at least one polymer.

139. The ink formulation of 134, wherein the composition comprises two or more metal salts.

140. The ink formulation of 134, wherein the composition comprises an epoxy.

141. A method of directly writing a conductive metal,

Providing a cantilever having a cantilever end, the cantilever may include a tip at its end or may be a tipless cantilever;

Providing an ink disposed at the cantilever end, the ink comprising metal nanoparticles;

Providing a substrate surface;

Contacting the cantilever end with the substrate surface such that the ink is transferred from the cantilever to the substrate surface

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142. The method of 141, wherein the ink forms a feature on the substrate surface and the feature is post-processed.

143. The method of 141, wherein the ink forms a feature on the substrate surface and the feature is heat treated.

144. The method of 141, wherein the ink forms a feature on the substrate surface and the feature is light treated.

145. The method of 141, wherein the ink forms a feature on the substrate surface and the feature is heat treated to about 300 ° C. or less.

This patent or application file includes at least one drawing written in color. Copies of this patent or patent application publication with color drawings are provided by the Office upon request and payment of the required fee.

Fig. Gold nanoparticles deposited between the gold electrodes. (A) and (D) are optical images of two lines of about 60 and 45 μm formed by drawing an ink cantilever along the surface, and the cantilever width was 60 and 45 μm, respectively. (B) and (E) are the same patterns as in (A) and (D) after reduction. The resistance measured across the gap for these patterns is 32 and 18 ohms. They survived the water rinse and Scotch tape tests as shown in (C) and (F), where the electrodes were peeled off but the patterns were not.

Figure 2. Gold nanoparticles deposited between the gold electrodes. (A) and (B) are optical images before and after curing of a line formed by drawing an ink cantilever of 15 mu m between two electrodes. The resistance measured across the gap for this pattern is 18 ohms. This pattern withstood the water rinse and Scotch tape test as shown in (C), where the electrodes were peeled off but the line pattern was not. (D) is a topographic AFM image of 14.5 μm wide lines and 90 nm high. (E) corresponds to the cursor profile of the manufactured line.

Figure 3. Gold nanoparticles deposited between the gold electrodes. (A) and (B) are optical images before and after curing of a line formed by drawing an ink cantilever of 15 mu m between two electrodes. The resistance measured across the gap for this pattern is 19 ohms. (C) is a topographic AFM image of 15.8 μm wide lines and 38 nm high in the red box region of (B). (D) corresponds to the cursor profile of the manufactured line.

Figure 4. Gold nanoparticles deposited between the gold electrodes. (A) and (D) are optical images before and after curing of a line formed by drawing a 10 μm ink cantilever (narrowed using a fib, cantilever shown in a yellow box) across two electrodes. The resistance measured across the gap for this pattern is 9 ohms. (B) and (E) are 11.5 μm topographic AFM images for 15.5 μm wide lines and 95 nm high and FIB tips in the red and blue boxes of (D), respectively. (C) and (F) correspond to the cursor profile of the manufactured line.

Figure 5. Gold nanoparticles deposited between the gold electrodes. (A) and (B) are optical images before and after curing of the line formed by drawing a 10 μm wide FIB cantilever across two electrodes. The resistance measured across the gap for the line pattern is 22 ohms. (C) is a topographic AFM image of 11.5 μm wide lines and 80 nm high in the red box region of (B). (D) corresponds to the cursor profile of the manufactured line.

Figure 6. Gold nanoparticles deposited between the gold electrodes. (A) and (D) are optical images of gold lines formed across two electrodes. The resistance measured across the gap for the line pattern is 190 ohms. (B) and (E) are topographic AFM images of 5 and 4 μm wide lines and 12 nm high in the red and blue boxes of (A) and (D), respectively. (C) and (F) correspond to the cursor profile of the manufactured line.

Figure 7. Gold nanoparticles deposited between the gold electrodes. (A) and (D) are optical images of gold lines formed across two electrodes. (B) and (E) are topographic AFM images of 3 and 2 μm wide lines and 8 nm high in the red and blue boxes of (A) and (D), respectively. (C) and (F) correspond to the cursor profile of the manufactured line.

Figure 8. A platinum / gold alloy ink deposited between gold electrodes on silicon oxide using a cantilever. Each line was formed by immersing the cantilever in an ink bottle filled with ink and drawing the line until the cantilever came out of the ink. Note the similarity of line shape and length.

Figure 9. A platinum / gold alloy ink deposited between gold electrodes on silicon oxide using adjacent cantilevers. Each of the three lines was made using a single cantilever or adjacent cantilevers loaded with ink. The left line was formed by drawing a 31 micron wide single cantilever across the surface until it came out of the ink. The widest middle line was formed using four adjacent 31 micron wide cantilevers, and the right line was formed using two adjacent 31 micron wide cantilevers. Note that the maximum length of the lines increases with increasing number of write cantilevers.

Figure 10. AFM height image of nanoscale palladium pattern on silicon oxide. Palladium acetate saturated in 80% ethylene glycol was patterned using PDMS coated silicon nitride AFM tips. The line scan of the cured pattern shows a height increase of 2 nm to 10 nm between the first and second layers.

Figure 11. AFM height image of nanoscale gold pattern on quartz. Gold nanoparticle inks were patterned by keeping the ink coated conventional silicon nitride AFM cantilever / tip in contact with the surface for 10 seconds with a constant force. The row of the rightmost dots (50 nm in diameter, 3.5 nm in height) was formed with a force of 0.2 nN, the middle dot row was formed with a force of 1.5 nN (65 nm in diameter, 6 nm in height), and the leftmost dot Rows were formed with a force of 4 nN (85 nm in diameter, 7.5 nm in height). The patterns were imaged immediately after patterning with the coated tip.

Figure 12. AFM height image of nanoscale gold pattern on quartz. Gold nanoparticles dissolved in mesitylene (“ink”) were patterned by translating the ink coated conventional silicon nitride AFM tip across the surface at a rate of 0.15 microns / sec. Line traces indicate that the height and width of the lines increase with applied force.

Figure 13. AFM height image of nanoscale gold pattern on quartz. Gold nanoparticles dissolved in mesitylene (“ink”) were patterned by keeping the ink coated conventional silicon nitride AFM tip in contact with the surface for 10 seconds. The resulting pattern was imaged after curing at 250 ° C. for 10 seconds using a heat gun. After curing, the height of the particle patterns decreases from about 30 nm to about 15 nm.

Figure 14. Optical image of a micron scale platinum line drawn with a silicon nitride cantilever across gold electrodes on a silicon oxide wafer. The platinum ink contained platinum chloride (100 mg in 15 microliters) dissolved in 80% ethylene glycol. The precursor ink was converted to metal by heating to 200 ° C. for 20 seconds on a hot plate. The line width after curing was about 5 microns.

Figure 15. Optical image of a micron-scale platinum line drawn and cured with a silicon nitride cantilever across chromium electrodes on a glass wafer. The platinum ink contained 100 mg of platinum chloride dissolved in a 15 microliter aqueous solution containing 30 mg of 300 and 10,000 molecular weight polyethylene glycol each. The precursor ink was converted to metallic platinum by heating at 250 ° C. for 10 seconds with a heat gun.

Figure 16. AFM height image of nanoscale gold features drawn between gold electrodes on silicon oxide. The gold precursor ink solution contains 100 mg of gold tetrachloride salt dissolved in 80% ethylene glycol / 20% water. Large particles were the result of three ink layers, each layer cured by heating to 200 ° C. for 10 seconds on a hot plate. This trace was not conductive.

Figure 17. Image of platinum-gold alloy pattern formed using AFM cantilever. The alloy precursor ink contained 100 mg of platinum salt and 50 mg of gold salt dissolved together in 30 microliters of water containing 60 mg of polyethylene glycol of 300 and 10,000 molecular weight, respectively. The traces were cured by heating at 250 ° C. for 10 seconds with a heat gun. (A) A two layer pattern drawn across a 30 micron gap between gold electrodes on a silicon oxide wafer. The resistance of this trace was 90 ohms. (B) Six layer pattern drawn between chromium electrodes on glass wafer. The resistance of this trace was 32 ohms. 17 (B) was performed using a PDMS DPN stamp tip. (C) AFM image showing a large particle microstructure of a platinum-gold alloy film, with a particle size of ˜150 nm.

Figure 18. Optical micrograph of large gold features on glass prepared by dropping epoxy / gold precursor ink on slide and then curing at 150 ° C. for 2 hours. Gold precursor inks were prepared by dissolving 85 mg of hydrogen gold tetrachloride in 50 microliters of dimethylformamide and then adding 1 microliter of ethylene glycol and 1 microliter of epoxy mixture to 3 microliters of this salt solution. The resistance of this membrane was 0.3 ohms.

Figure 19. AFM height image of a gold pattern formed by depositing a gold precursor on quartz using a PDMS coated silicon nitride AFM tip. Gold precursor inks were prepared by dissolving 85.5 mg of gold tetrachloride in 50 microliters of dimethylformamide. To this solution is added 1 microliter of ethylene glycol and 0.1 mg of thiothiic acid. A 4.5 × 4.5 square micron pattern was cured by heating at 250 ° C. for 10 seconds with a hot air gun. The one layer pattern was 15 nm high after curing (see line trace).

Figure 20. Direct entry of gold lines on silicon nitride substrates using commercial silver nanoparticle inks. (A) is an optical image of a 200 micrometer long silver ink line after direct writing, (B) is the resulting silver microstructure after low temperature curing, and (C) is a topographic of a small portion of the line and the corresponding average height profile An AFM image, this line has a thickness of 117.9 nm.

Figure 21. Optical image showing cantilever microdeposition of commercial silver nanoparticle inks on glass substrates before and after curing.

Figure 22. Deposition and Low Temperature Curing of Commercial Silver Nanoparticle Inks on Glass Substrates Coated with Chromium Thin Films. Laser ablation was used to form a gap in the chromium film and expose the lower glass substrate (in the center of the image). Two lines were then drawn on the chromium film on each side of and across the gap using a tipless cantilever.

Figure 23. Optical image showing manufacture of multilayer lines by repeat drawing.

(1L) 1 layer line with 6 micrometer width and 30 nm thickness.

(2L) Two layer line with 8.6 micrometer width and 41 nm thickness.

(3L) 3 layer line with 8 micrometer width and 70 nm thickness.

Figure 24. Coating tipless cantilever with ink by immersion in a microfabricated reservoir. (A) is a plan view optical image of a cantilever directly above the ink pool in a millimeter-wide circular reservoir (made by deep reactive ion etching of a silicon wafer, the lower part of the image), and (B) when soaked in the ink pool Is an optical image. Note the meniscus around the cantilever of image B.

Figure 25. Optical image showing repair of a thin film transistor (TFT) flat panel display.

Figure 26. Schematic of a tipless cantilever with ink storage slit.

Figure 27. Drawing showing four alternative designs for a tipless slit cantilever.

Figure 28. Optical image showing deposition of commercial silver ink on a glass substrate using a slit cantilever.

Figure 29. Two examples of deposition and curing of lines consisting of silver nanoparticle inks across the gap between gold electrodes on a glass substrate when using a slit cantilever.

Figure 30. Line filling with slit cantilevers loaded with gold nanoparticles / 1, 3, 5-TEB ink.

Figure 31. A diagram showing a mechanism for repairing flat panel displays and similar objects. This instrument repairs gaps in conductive traces using cantilevers or cantilever microbrushes coated with metal precursor inks. The XYZ stage controls the high resolution movement of the cantilever. An ink supply mechanism including an ink bottle and its protective cover supplies material to the cantilever before the touchdown operation. A rough Z moving stage is provided to supply ink to the cantilever and to contact the surface, and a rotating stage can position the cantilever at any angle with respect to the Z axis. Monitoring of the cantilever's brightness (varies with bending) through video imaging using an embedded camera system and appropriate image processing software detects the touchdown of the cantilever on the surface when the cantilever is first brought into contact with the surface. A laser system is provided for (thermally) curing the micro deposited material.

Figure 32. Schematic showing a second mechanism for plate repair. In this design, the output of the laser reflection sensor is monitored when the sensor measures the Z position of the cantilever to detect the touchdown of the cantilever on the substrate surface. As in the previous design, the XYZ stage at several nanometers resolution provides cantilever movement, and a laser (not shown) cures the deposition material (ink). The ink supply mechanism supplies the material (ink) to the cantilever before the touchdown operation. The massive Z stage provides massive Z movement for ink supply, and the rotating stage can position the cantilever at any angle with respect to the Z axis.

Figure 33. An alternative design of the FPD repair mechanism is shown, in which the common focal length measurement element detects the touchdown of the cantilever on the substrate surface.

Figure 34. Indicating the deposition of conductive gold traces deposited from 5 micron tipless cantilevers loaded with gold nanoparticle ink across insulating gaps of various widths (10, 20, 40 micrometers) between conductive ITO (indium tin oxide) electrodes. Optical image.

Figure 35. A diagram showing how gaps can be formed near topography steps when drawing lines using a tipless cantilever.

Figure 36. A diagram showing the loading and fabrication of (conductive) lines of the micron scale by direct writing using a tip-free cantilever coated with ink followed by curing. Experimental curing conditions suitable for low temperature curing inks such as gold nanoparticle inks are indicated.

Figure 37. A diagram showing how line width is controlled (proportional) by cantilever width.

Figure 38. Experimental results showing how the line width is controlled (proportional) by the cantilever width. (A) A 10 micron wide cantilever is shown for writing lines of similar width. (B) A 2 micron cantilever is shown that writes about 2 micron lines. Both images have the same scale for easier comparison of the width of the lines.

Figure 39. Optical and AFM images (A and B, respectively) of conductive gold traces deposited across a 200 micrometer gap between chromium electrodes. Gold nanoparticle / mesitylene / decanol mixtures (described in further examples) were used in this experiment. The ink was converted to a low resistivity metal form by performing high temperature curing at 250-300 ° C. for 7 minutes and then low temperature curing at 120 ° C. for 60 minutes.

Figure 40. Adhesion test. Monolayer gold lines were deposited on glass on three adhesion test samples and cured at 150 ° C. for ˜ 10 seconds. The tape peel test showed no loss of adhesion to the substrate and the lines survived chemical cleaning.

In a preferred embodiment, the invention, which may be referred to as "cantilever microdeposition" (CMD) for convenience, may be practiced in various embodiments, including those described below in the Examples.

Embodiment 1: Cantilever  Micro composure

In a first embodiment, the present invention provides a method for producing a pattern of micrometer scale and submicrometer scale using cantilever or microbrush, the method comprising: (1) providing a cantilever or microbrush; (2) providing an ink meaning a compound or mixture thereof disposed on the cantilever or microbrush; (3) providing a substrate surface; And (4) contacting the microbrush with the substrate surface such that ink is transferred from the cantilever to the substrate surface. 36 illustrates the principle of this method.

Preferably, the minimum lateral dimension (measured parallel to the substrate surface, eg the width of the line) of the resulting pattern is in the range of 0.5 microns to 15 microns. Its maximum lateral dimension (e.g., the length of the line) is greater than 100 microns, preferably 200 microns, and its height (e.g., measured substantially perpendicular to the local plane) is from 1 nanometer to It is in the range of 2 microns.

Preferably, the cantilever or microbrush is a microelectromechanical system manufactured using standard microfabrication techniques, including but not limited to photolithography, electron beam lithography, thin film deposition, etching, lift-off and focused ion beam micromachining. MEMS). The microbrush may be in the form of a cantilever having a free end and an end coupled to a macro or mesoscale body, or may be a device comprising a plurality of cantilevers. The cantilever (s) may or may not have tip (s) protruding from the main plane of the cantilever. The meso / macroscale body may be a diced (silicon or glass) wafer.

Two or more neighboring cantilever bodies may form fixed or variable width gaps or slits that can be used for ink storage or dispensing. Microfluidic circuitry may be formed on / in the cantilever body and / or the meso or macroscale body to which it is attached. The microfluidic circuit can include reservoirs, channels, and vias for ink delivery. The channel and reservoir may be formed by two substantially parallel surfaces (eg, the walls of the slits described above) or by three or more surfaces (eg, forming an open channel or a fully sealed channel). . In a preferred embodiment, a substantially flat tipless cantilever is used.

Many inks include organic and inorganic compounds, including metal salts and complexes, sol-gel precursors, polymers, nucleic acids such as nucleic acids (eg DNA), peptides and proteins, nanoparticles and solutions or mixtures thereof Can be. Numerous treatments may precede or follow deposition, including substrate cleaning, surface preparation, hole drilling, micromachining with lasers or ion beams, photolithography and curing by application of heat or light.

Literature useful in the practice of the present invention

Cantilevers, tips, inks, substrate surfaces and contacting methods are known in the art and those skilled in the art can refer to the following technical literature for the practice of the invention in many embodiments, including the preferred embodiments and examples described below. Can be. In addition, a list of references is provided later in this specification, and all references within this specification are incorporated by reference in their entirety and may generally be relied upon to practice the present invention.

Cantilever microdeposition is associated with, but is different from, Dip Pen Nanolithography ^™ (DPN ^™ ) printing, a technology commercially developed by NanoInk, Inc. (Chicago, Illinois). In technology, (1) a sharp tip with nanometer scale vertices is usually coated with ink, and (2) the ink flows from the tip to the substrate through a meniscus that naturally condenses at the contact junction. The present invention does not require a sharp tip, unlike DPN printing, but rather preferably uses a flat spatula-shaped cantilever or cantilevers as ink application means. Cantilever microdeposition is best used for the manufacture of patterns with critical dimensions ranging from high submicrometers to 10 microns, while DPN printing is best used for patterning at very high resolutions (eg nanoscale).

Cantilever microdeposition is low in resolution, but its throughput (square microns per second) is higher than DPN printing, especially since higher speeds (of cantilevers or microbrushes on the surface) can be used. In general, the cantilever used in the present invention does not directly contact the substrate surface. Rather, an ink layer is trapped between the surface and the microbrush or cantilever end. Without being bound by theory, it is believed that the interaction of fluid dynamics and capillary stress in the space between the cantilever and the surface controls ink deposition. For example, pattern height and overall quality (continuity) are sensitive to the pressure applied to the cantilever, while in DPN this is generally not the case. The line width is highly correlated with the cantilever width (see, for example, FIGS. 37 and 38), and is usually independent of the patterning speed, but in contrast with DPN printing this is the diffusion rate of ink from the point source (tip-sample contact). And the patterning speed.

However, many technical developments related to deep pen nanolithography, including but not limited to inks, ink delivery techniques, cantilever / brush manufacturing processes, cantilever position control techniques, and computer controlled design and manufacturing algorithms, are largely associated with cantilever microdeposition.

Various products related to DPN printing, including deposition tools (e.g., NSCRIPTOR platform), computer software, environmental chambers, pens, substrates, kits, inks, ink bottles, calibration software, alignment software, accessories, etc., are available from NanoInk Can be. Single DPN printing probes, passive multi-probe arrays, A frame cantilevers, diving board shaped cantilevers, as well as AC mode cantilevers can be obtained from the nanoink. In addition, sharp and unsharp tips can be obtained. Dip Pen Nanolithography ^™ and DPN ^™ are trademarks of NanoInk, Inc. (Chicago, Ill.) And are used appropriately herein.

DPN printing and deposition methods are described broadly in the following patent applications and patent publications, which are hereby incorporated by reference in their entirety and in support of the present disclosure, in particular with respect to experimental parameters for carrying out deposition. :

1. US Provisional Application No. 60 / 115,133, filed January 7, 1999 ("Deep Pen Nanolithography").

2. US Provisional Application No. 60 / 157,633, filed Oct. 4, 1999 ("Method and Product Made therein Using Scanning Probe Microscope Tips").

3. U.S. Patent Application Serial No. 09 / 477,997, filed Jan. 5, 2000 ("Method and Product Made for or Using Scanning Probe Microscope Tips"), now dated October 21, 2003 US Patent No. 6,635,311 to Mirkin et al.

4. U.S. Provisional Application No. 60 / 207,713, filed March 26, 2000 ("Method and Product Made therein Using Scanning Probe Microscope Tips"). This application describes, for example, wet chemical etching, examples, references and drawings, all of which are incorporated by reference in their entirety.

5. US Provisional Application No. 60 / 207,711, filed May 26, 2000 ("Method and Product Made therein Using Scanning Probe Microscope Tips").

6. U.S. Application No. 09 / 866,533, filed May 24, 2001 ("Method and Product Made therein Using Scanning Probe Microscope Tips"). This application describes, for example, a wet chemical etch, embodiment (eg, FIG. 5), references and drawings, all of which are incorporated by reference in their entirety.

7. US Patent Publication No. 2002/0063212, published May 30, 2002 ("Method and Product Made therein Using Scanning Probe Microscope Tips").

8. United States Patent Publication No. 2002/0122873, published Sep. 5, 2002 ("Nanolithography Method and Products for or Produced thereby").

9. PCT Publication No. WO 00/41213, published July 13, 2000, based on PCT Application PCT / US00 / 00319, filed January 7, 2000 (" method for using a scanning probe microscope tip and for or Products produced thereby ").

10. PCT Publication No. WO 01/91855, published December 6, 2001, based on PCT application PCT / US01 / 17067, filed May 25, 2001 ("Methods and methods for using the scanning probe microscope tip or Products produced thereby ").

11. US Provisional Application No. 60 / 326,767, filed October 2, 2001 to Merkin et al. (“Protein Array with Nanoscale Features Created by Deep Pen Nanolithography”), now published April 10, 2003. 2003/0068446.

12. US Provisional Application No. 60 / 337,598 (patterning of nucleic acids by deep pen nanolithography), filed November 30, 2001 to Merkin et al., And US Application No. 10 / 307,515, filed December 2, 2002.

13. US Provisional Application No. 60 / 341,614, filed December 7, 2001 to Merkin et al. (Patterning of solid state features by deep pen nanolithography), currently published on August 28, 2003, 2003/0162004. This application includes descriptions of metals, metal oxides and inorganic solid structures.

14. US Provisional Application No. 60 / 367,514, filed March 27, 2002 (Eby et al., "Method and Apparatus for Aligning Patterns on a Substrate") and Publication 2003, published October 2, 2003. / 0185967.

15. US Provisional Application No. 60 / 379,755, filed May 14, 2002 to Cruchon-Dupeyrat et al. And US formal application No. 10 / 375,060, filed February 28, 2003.

16. Also, U.S. Patent Application No. 10 / 647,430 filed August 26, 2003 (currently published as 2004/0127025) (" Process for producing conductive patterns using nanolithography as patterning tool. ") Describes various metal inks that can be patterned in accordance with the present invention, which is incorporated by reference in its entirety (many portions of text are provided below for those skilled in the art to practice the present invention). In addition, U.S. formal application, such as Krutch-Dupeirat, published Feb. 2004, 2004/026681 ("Protosubstrates"), described a variety of methods for printing micro and nanostructures that can be tested at macro scale. Embodiment is described and the whole is reflected by reference. In addition, US Patent Application Publication No. 2004/0008330 ("Electrostatically Driven Nanolithography") of Merkin et al., Published January 15, 2004, describes the patterning of conductive polymers, the entirety of which is incorporated by reference. have. In addition, US Patent Application No. 10 / 442,189 ("Peptide and Protein Nanoarrays and Direct Writing Nanolithography Printing of Peptides and Proteins", filed May 21, 2003) is incorporated by reference in its entirety. , Various peptides and proteins that can be patterned according to the invention are described. In addition, US Patent Application No. 10 / 689,547 ("Nanometer Scale Engineering Structure ...", filed by Van Crocker et al. On October 21, 2003, is incorporated by reference in its entirety. In addition, US Patent Application No. 10 / 705,776 ("Method and Apparatus for Ink Delivery") filed on November 12, 2003 by Kruchten-Dupeirat et al. Is incorporated by reference in its entirety. .

In general, the latest DPN ^™ printing and deposition related products, including hardware, software and instruments, are also available from NanoInk, Inc., Chicago, Ill., Which can be used to carry out the present invention. For example, the NSCRIPTOR ^™ instrument can be used for patterning. DPN printing is described, for example, in Ginger, Zhang and Mirkin, Angew. Chem. Int. Ed., 2004, 43 (1), 30-45.

Parallel methods of the DPN printing process can be performed, for example, as described in US Pat. No. 6,642,129, issued Nov. 4, 2003.

In addition, the following articles describe wet chemical etching procedures used with direct write nanolithography, which are incorporated by reference in their entirety, including the drawings, references, and examples: Zhang et al., "Dip -Pen Nanolithography-Based Methodology for Preparing Arrays of Nanostructures Functionalized with Oligonucleotides "]; Adv. Mat., 2002, 14, No. 20, October 16, pages 1472-1474; Zhang et al., "Biofunctionalized Nanoarrays of Inorganic Structures Prepared by Dip-PenNanolithography"; Nanotechnology, 2003, 14, 1113-1117; Zhang et al., "Fabrication of Sub-50 nm Solid-State Nanostrcutures on the Basis of Dip-Pen Nanolithography"; Nano Lett., 2003, 3, 43-45. In addition, US patent application "Preparation of solid state nanostructures including sub-50nm solid state nanostructures based on nanolithography and wet chemical etching" (10 / 725,939, filed December 3, 2003 by Merkin et al.) Etching and monolayer resists that can be used in the present invention are described, the entirety of which is incorporated by reference.

The textbook Fundamentals of Microfabrication, The Science of Minitaturization, 2nd Ed., Marc J. Madou discusses micro and nanotechnology, including addition and reduction methods, such as lithography (chapter 1) and pattern transfer using dry etching methods. (Chapter 2), Pattern Transfer Using the Addition Method (Chapter 3) and Wet Bulk Micromachining (Chapter 4) are described. In addition, the textbook Direct-Write Technologies for Rapid Prototyping Applications: Sensors, Electronics, and Integrated Power Sources (Eds. A. Pique and D. B. Chrisey) describes micro and nanotechnology, including methods of addition and reduction. For example, bulk micromachining and etching are described on pages 617-619. DPN printing on a sub 100 nanometer long scale is described in Chapter 10.

Additional embodiment

Embodiment 2: Micro for Forming Conductive Metal and Other Patterns composure  And curing

For example, in a preferred embodiment, the present invention provides a method comprising the steps of: (1) providing a cantilever having a cantilever end, the cantilever may comprise a tip at the end or may be a tipless cantilever; (2) providing ink disposed at the cantilever end; (3) providing a substrate surface; And (4) contacting the cantilever and the substrate surface such that ink is transferred from the cantilever to the substrate surface. Preferably, a local thermal curing step is followed by deposition, for example using a medium power laser or infrared gun.

In another preferred embodiment, stamp tips are used to deposit the material described below. Stamp tips are filed, for example, on February 13, 2004, filed under the title “Direct-Write Nanolithography with Stamp Tips: Fabrication and Application”. U.S. Provisional Application No. 60 / 544,260 to H. Zhang et al. And U.S. Patent Application No. 11 / 056,391, filed February 14, 2005, which are hereby incorporated by reference in their entirety. have.

Cantilevers are known in the art and can be obtained, for example, from MicromarshMasch USA (Portland, Oregon). Cantilevers can be coated and functionalized as desired. Tipless cantilevers are also described in this field as described, for example, in US Pat. No. 5,958,701 to Green et al., US Pat. No. 6,524,435 to Agarwal et al. And US Pat. No. 6,573,369 to Henderson et al. Known in

An important feature of the present invention is that the geometry and shape of the cantilever can be used to control at least one dimension of the features formed from the ink on the substrate surface.

Although the main embodiments of the present invention are often metal-based inks including both metal precursor inks and metal nanoparticle inks using metal salts, the ink is not particularly limited. Useful embodiments are described above and further in the 16 patent application (conductive pattern) described below.

In general, the three main ink components comprise (1) the main material to be deposited, for example one or more metals or metal salts, (2) one or more solvents, and (3) one or more additives, if desired. The components of the ink can be adjusted to function with the cantilever, the tip, if present, and the substrate.

The ink can be completely or partially dried on the cantilever or cantilever tip, if desired, before being delivered to the substrate surface. The ink may be completely or partially dried on the substrate surface after delivery.

Although the main embodiment of the present invention is a metal-based ink, the nanoparticles of the ink are not particularly limited. Inorganic compounds may be used for the nanoparticles. Nanoparticles can be substantially homogeneous or heterogeneous. Nanoparticles can have a core-shell structure if desired. Nanoparticles can have an organic surface coating or shell if desired. Nanoparticles can be magnetic in nature. Nanoparticles can be virtually doped or undoped semiconductors. Nanoparticles can be electrically insulating or have an insulating shell. Nanoparticles can be hydrophilic or hydrophobic. Nanoparticles can also be precursors to conductors, magnetic materials including ferromagnetic materials, semiconductors and other technically useful materials including optical materials. Nanoparticles exhibit a quantum limiting effect and can exhibit useful properties such as, for example, electric luminescence and light luminescence of various colors. Nanoparticles can be functionalized to chemisorb or covalently bond to a surface.

The solvent system is not particularly limited. Solvent inks with high boiling points are generally preferred. For example, a solvent having a boiling point above about 100 ° C., particularly above 500 ° C., may be used. Aromatic hydrocarbons, for example, are a type of solvent with high boiling points.

The ink may begin drying as desired to form features that are preferably stabilized over time, for example after one month upon delivery to the substrate surface. Preferably, the features can be cured to be stable to rinsing with a solvent including the active solvent and the etching system. Features can be exposed to annealing, light, lasers, currents and other stimuli.

Often, for example, it is desirable to form a plurality of continuous structures that provide high electrical conductivity. Often, it is desirable to form a high quality contact between a feature and another feature on the surface or surface, for example electrodes.

The features can be nanostructured or microstructured. The height of the features is not particularly limited since the lamination can be performed to build the height. The methods described herein can be used to prepare nanoscale and microscale dimensions so that side dimensions such as length and width are not particularly limited. For example, the dot diameter or line width can be, for example, about 5 nm to 1 micron. Alternatively, the dot diameter or line width can be, for example, about 1 micron to 100 microns, or about 5 microns to about 25 microns.

Additional references are described throughout the remainder of the specification for use in practicing the present invention. It is not allowed that any of these references are prior art. The invention is further illustrated by the following non-limiting examples.

Example

In the following example, gold and platinum traces were written by this new method to form low resistivity traces that strongly adhered to a substrate such as glass. The examples are subdivided into (1) experimental parts, and (2) results and explanations.

Experiment

material

All metal salts were purchased with the highest purity available from Aldrich (Milwaukee, WI). Silicon nitride cantilevers of different beam widths with or without tips were prepared through standard micro fabrication methods. To further test the effect of cantilever width, some cantilevers were narrowly machined using focused ion beam (FIB) technology.

Nanoparticle Preparation

Nanoparticles are described in M. J. Hostetler, et al., Langmuir 14, 17 (1998)], using the method described by Murray and his colleagues.

Patterning

Micron sized patterns were formed using a translational stage of thermal microscopy CP research instruments or NSCRIPTOR (Nano Ink, Chicago, Ill.) Instruments. The cantilever was coated with different metal precursor inks by using a z stepper motor to contact the cantilever with ink-filled microfabricated ink bottles. The z motor and x-y translational movement stage were then used to place the coated cantilever on the substrate and to contact the cantilever with the surface. The cantilever was contacted at a slight angle (capital) such that only the end of the cantilever contacted the surface. A slight bending of the flexible cantilever monitored by the optical microscope indicated that contact was made. Note that in order to pattern the features of the micron scale, it was not necessary to use the force feedback and piezoelectric scanning / positioning functions of the instrument. However, for nanoscale patterns, these fine positioning functions provided control of feature size and alignment at submicron and in some cases sub 100 nm scales.

Results and discussion

ink composure

New methods have been developed for writing ink directly on surfaces that enable line and dot patterns with dimensions on the order of hundreds of microns and sub-microns. The ink delivery method included the following general steps:

Ink loading. Ink was loaded into the flexible cantilever. Depending on the application, the cantilever may have a sharp tip at the end or may be tipless, and may have various end shapes and widths of several microns to several hundred microns. Ink loading can be performed manually by contacting the cantilever with ink droplets or reservoirs and then removing them. The ink wets the lower side of the cantilever and adheres through cohesive force. Passive loading and delivery of ink has been demonstrated in the examples. Liquid inks are actively attracted and seeded to control deposition through electrowetting and dielectrophoresis. Methods described by C. Bergaud and colleagues may also be used.

approach. The cantilever can be in contact with the surface for patterning. In most cases, neither a laser force feedback mechanism nor a scanning / positioning mechanism is required. A mechanical "Z" stepper motor can be used to contact the cantilever with the surface, and an optical microscope can be used to detect defects of the cantilever when the cantilever is in contact with the surface.

Feature Control. A cantilever can be drawn along the surface to form a line pattern. In NSCRIPTOR and thermal microscope CP research platforms, levers can be translated along the surface in the form of a desired pattern using "X" and "Y" stepper motors or fine manual positioning screws. Commercial high resolution piezoelectric stages (NPoint, Madison, WI) can be retrofitted in either instrument. Custom pattern design software can be used with the NSCRIPTOR platform to direct the movement of the cantilever. Importantly, when the cantilever is moved along the surface in the long axis direction of the cantilever, the width of the line can be directly related to the width of the end of the cantilever as shown in FIG. Therefore, the shape of the line, for example the width of the line, can be controlled through the cantilever geometry. Using standard microfabrication techniques, cantilevers having a width of about 1 micron to about 100 microns can be prepared. Thus, using this method, a line pattern having a width of about 1 micron to about 100 microns can be formed. A large range of line widths that can be patterned using various cantilever structures is shown in FIGS. For example, Figure 1 shows an optical image of 60 and 45 micron wide lines. 6 shows optical and AFM height images of 5 and 4 micron wide lines, and FIG. 7 shows 3 and 2 micron wide lines. Even at the narrowest line widths, the lines are sufficiently continuous to yield low resistivity as low as 4 μΩcm.

Best feature control was achieved using straight beam shaped cantilevers, and the "V" or "A" cantilevers did not form a line of controlled width. In addition, various cantilever spring constants (ie, hardness from 0.004 N / m to 0.19 N / m) and lengths (150 to 300 microns) can be used to achieve control over the line shape. In addition, the optimum length of a fixed width cantilever depends on the spring constant of the material. In practice, very good line control was achieved using a 15 micron wide cantilever with a spring constant of 0.032 N / m and a length of 150 microns, but a 15 micron wide with a spring constant of 0.004 N / m and a 300 micron length By using the cantilever, only proper line control was achieved. Advanced lithographic methods such as focused ion beams can be used to further reduce the dimensions of the cantilever by milling. Note that the process is the same when the surface moves while the cantilever is stationary. Using current instruments, a line about 100 microns wide can be produced, and traces with higher conductivity are obtained from a writing speed of 10 microns / sec, but less than 1 micron in a single cantilever pass at a speed of 20 microns / sec. The line can be manufactured.

Feature height control. By controlling several patterning variables, you can change the height of the line trace. In general, the thickness of the line pattern formed by a single pass may be between 1 nm and several hundred nanometers after curing (see next section). To ensure optimal control of the shape of the line, the cantilever contacts the surface at an angle greater than several degrees, not parallel to the surface. The height of the trace can be changed by controlling the distance between the cantilever and the surface, the force or bending of the cantilever, and the tip movement speed.

When the cantilever is pressed against the surface with a strong force, the height of the patterned trace decreases. In order to achieve the optimum height per pass for the metal ink, the distance between the cantilever and the surface can be maximized as much as possible without breaking contact. Thus, the use of inks with greater viscosity and higher metal concentrations allows for higher patterns using this method. In preliminary experiments, the force was roughly controlled by changing the separation between the cantilever and the surface while monitoring the cantilever deflection. The piezoelectric material can be inserted into the cantilever to further improve height / force control by sensing the force between the cantilever and the substrate during access to and patterning of the surface. Qualitative observation meant that another method of increasing the height of the pattern decreased the speed of movement of the cantilever during patterning. With slow tip movement, features (after curing) of 100 nm height can be formed in a single pass. In order to form a dot pattern, the cantilever is contacted with the surface and removed after maintaining contact for a predetermined time (usually several seconds).

Split and multiple cantilevers. By changing the cantilever geometry, it is possible to increase the maximum ink loading and thus the maximum line length. With a single cantilever of 50 microns to 200 microns in length, as shown in FIG. 8 for two different tip structures, a single loading step yields reproducible lines of several hundred microns in length. Writing with adjacent cantilevers with very small gaps (microns) in between can greatly improve the total supply of ink (ie, the volume available from a single dip). Increased ink supply can yield higher patterns or longer line patterns. The slit or gap between the cantilevers can function as a reservoir for holding ink due to capillary motion. When the cantilevers are closely spaced (a few microns to 10 microns), this method may be used to increase the line width of the trace. Alternatively, when multiple cantilevers are further spaced apart, they can be used to form the dot or line patterns of the same or different inks in parallel. 9 is an optical image of patterned lines formed using multiple adjacent cantilevers. Note how the maximum line length obtained (and thus the ink loading) increases with increasing number of cantilevers (1, 4, 2 adjacent cantilevers) in the 'pen'. It is also noted that the increase in line width is proportional to the number of cantilevers in the pen.

Laminated. By forming a plurality of layers, the height of the line and dot patterns can be increased. In general, for metal inks, each layer is first cured by heating before a second layer of the same metal precursor ink is formed. Nanoscale two-layer palladium pattern is shown in FIG. 10 with AFM image and line scan. Note the height increase from 2 nm for the first layer to 10 nm for the second layer. The ink used in this experiment was a saturated solution of palladium acetate dissolved in 80% ethylene glycol: 20% water. For other applications, it may be necessary to form stacked features of different materials such as metals, oxides, and semiconductors. In this experiment, the substrate was removed from the patterning device to cure each layer, but the improved device can include an energy source that can anneal or sinter the ink as it is deposited on the substrate. The energy source may be a heated sample stage for thermal curing, a laser or other light source, or a method of applying a current to the substrate to induce conversion of the ink into the final metal or metal oxide form.

ink. General methods of patterning conductive features include selecting appropriate precursor inks and dispersants; Applying ink to a surface, for example using the method described in the previous section; And finally converting the precursor material to the final desired material by processing the pattern by applying energy such as, for example, heat. In this section, two different nanoparticle ink strategies suitable for this patterning method are described. For certain applications, it may also be useful to use variations or combinations of different inks.

1. Monolayer Protective Nanoparticle Ink

Due to the high melting point of the inorganic materials, writing them directly onto the substrate is generally undesirable. However, nanoparticles (less than 100 nm in diameter) of many materials show extreme melting point drops (about 1000 ° C.) compared to bulk materials. Thus, nanoparticles provide a route of ink for direct write deposition of metals and metal oxides that can be converted to continuous films at low temperatures. This principle has also been applied to others, for example in combination with ink jet technology. Jacobson et al. (US Pat. No. 6,294,401) formed II-VI semiconductor patterns starting from nanoparticle inks such as CdTe and CdSe (see Ridley et al. Science 1999 286 746-749). The best nanoparticles for direct writing inks are readily dispersed in carrier solvents or matrices, have good stability at atmospheric conditions, can be prepared cheaply, and can be converted cleanly into continuous films at low temperatures.

Ink ready. Various alkanthiol capped gold nanoparticles were prepared according to the method described by Hostetler, Murray et al. This method has also been used to prepare other metal nanoparticles such as platinum, palladium and silver. In addition, many similar methods exist for preparing stable nanoparticles of other metals that are equally useful for such applications. These methods utilize a variety of surfactants, lipids, and polymers to prevent particles from clumping. However, the Hostelller, Murray method was chosen because this method is relatively straightforward and produces stable particles that can degrade into metal films at low temperatures. Subramanian and colleagues have reported that the temperature at which nanoparticles are converted into continuous membranes is largely related to the number of carbons in the stabilizing surfactant and the diameter of the nanoparticles, and shorter chains and longer particles decompose at lower temperatures ( Huang, J. Electrochem. Soc. 2003, 150, G412.).

Hexanethiol was chosen for the hydrophobic particles and chioct and mercaptosuccinic acid were chosen for the hydrophilic particles. After the particles were synthesized according to the procedure described by Murray and colleagues, the ink was prepared by dispersing the particles in a high boiling solvent such as mesitylene, xylene and dimethylformamide to reduce evaporation of the ink.

Nanoparticle Ink Deposition and Conversion to Metal. In order to obtain an ink suitable for the relevant substrate, it is generally useful to select a thiol capping surfactant and solvent that can cause the ink to wet the surface. For example, when nanoparticles are prepared using hexanethiol as a surfactant, the nanoparticles are hydrophobic and are well dispersed in nonpolar solvents such as toluene, mesitylene, and xylene. These inks have been very useful for patterning hydrophobic or unclean surfaces. On the other hand, nanoparticles prepared with thiotitic acid or mercaptosuccinic acid are dispersed in relatively polar solvents such as alcohols, thus they have been used for patterning on hydrophilic surfaces including cleaned glass, quartz, silicon oxide, silicon, and silicon nitride. . When the ink is not suitable for the surface, the ink does not form a continuous line and does not wet the surface and forms droplets. Some nonpolar solvents, such as mesitylene, have been useful for both hydrophilic and hydrophobic glass surfaces. After depositing the ink on a suitable substrate, the nanoparticle patterns were converted to continuous metal form by heating the surface with a hot air gun at 250 ° C. for several seconds. In principle, nanoparticles can be converted to bulk metal using many different energy sources, including lasers or heating stages, as long as the temperature is sufficient to remove the insulating organic shell. In Figures 1-7, the optical image shows gold traces written between two gold electrodes before and after curing, and an AFM line scan showing an average height of about 12 nm to 90 nm can be obtained using a single ink layer. Can be.

Surprisingly, the addition of long chain carbon compounds, for example C-5 to C-50, preferably C-10 to C-18, gives improved results. Preferably, the long chain carbon has a boiling point of at least 200 ° C. Similar to the ink compositions of the examples shown in Figures 1 and 2, high boiling long chain carbon compounds (preferably 10 to 18 carbons) were added to the ink formulation. For example, dodecane or pentadecane having boiling points of 215 and 270 ° C., respectively, can be used. In the example shown in Figs. 3-7, pentadecane 1-2 microliters was added to 4 microliters of nanoparticle solution consisting of (nanoparticles, mesitylene and thiothiic acid). Reaction with the carbon chains of the phase to form a three-dimensional structure by interlocking with each other to form a continuous and homogeneous film as compared to the optical image of FIGS. 1 and 2 as shown in the optical image of FIGS. By comparing the AFM images of FIG. 2D with 3C, 4A, 4B, 5C, 6B, 6E, 7B, and 7E, few cracks or holes were observed in FIGS. 3-7 and compared with FIG. 2D where holes and cracks are present. When cured, a relatively flat surface is formed after curing. The addition of long chained carbon reduced the evaporation rate on the surface or in the ink bottle by two hours for pentadecane in minutes for mesitylene, which is due to the homogeneous lines shown in the optical image of FIGS. Helped to form.

Characteristics of gold traces. Surprisingly, although the properties of the capping group can play an important role in adhesion, gold films prepared from nanoparticle precursors adhered very well to the cleaning glass surface (see FIG. 40). For example, nanoparticles prepared using an acidic thiol capping group, such as thiothiic acid, formed films on glass that survived the Scotch tape test, in which a strip of tape was placed on a pattern and rubbed off. However, the hydrophilic membranes on these glasses were removed by rinsing with water. On the other hand, the cured film formed of hydrophobic gold nanoparticles (i.e., capped with a methyl alkanthiol such as hexanethiol) was removed by the Scotch tape test, but the water rinse treatment withstood. The best comprehensive adhesion and conductivity was obtained by combining gold nanoparticles with hydrophilic and hydrophobic agents. In particular, organic soluble inks were made by dissolving nanoparticles prepared with hexanethiol in mesitylene and then adding 100 mg / ml of thiothiic acid. The monolayer pattern of this hybrid ink was kept intact after the Scotch tape adhesion test and resisted water rinsing. In practice, this ink had good writing properties, was well wetted to the glass substrate during writing, and was cured clean at 250 ° C. Evidence of good resistance to Scotch tape and rinse tests is shown in FIGS. 1 and 2. The resulting gold thin film is a yellow metal about 50-100 nm thick as measured by AFM and shows good conductivity when measured by a two probe configuration. For example, traces such as those shown in FIG. 2 with a length of about 250 microns and a width of 15 microns, have a measurement resistance of about 18 ohms. Thus, the resistivity of 8 μΩcm was measured for this particular trace, and the resistivity of pattern traces as low as 4 μΩcm was measured. For reference, the bulk resistivity of gold is 2.44 μΩcm. Similar results can be obtained by preparing the ink from nanoparticles having a ratio of acidic thiols and hydrophobic methyl-terminated thiols. Particles with different proportions of different thiol capping molecules are prepared in situ, or by Hostelller and colleagues (MJ Hostetler, SJ Green, JJ Stokes, and RW Murray, J. Am. Chem. Soc. 1996, 118). 4212-4213). Although gold particle inks have been demonstrated in this example, the present patterning method can generally be applied to any nanoparticle material that can be prepared with a capping ligand. Various reports have been made in the literature of procedures for making particles having a size in the range of less than 1 micrometer to 100 nanometers from materials including Cu, Pd, Ag, Ru, Mo, CdSe, Ni, Co and the like.

Nanoscale pattern using nanoparticle ink. Nanoparticle based ink formulations can be patterned using a deep pen nanolithography printing method to form a submicron sized pattern. In one experiment, hexanethiol capped gold nanoparticles (saturated solution of mesitylene) were patterned on quartz using a silicon nitride cantilever / tip assembly. In particular, the tip was coated with nanoparticle ink by contacting the tip with a drop of nanoparticle ink in a silicone ink bottle for several seconds. The coated tip was then used to form line and dot features on the quartz surface. For example, as shown in Fig. 11, a dot pattern was formed by keeping the tip in contact with the surface for 10 seconds. By varying the applied force from 0.2 nN to 4 nN, the diameter and height of the dots were varied from 50 nm to 85 nm wide and from 2.5 nm to 7.5 nm high. Lines were formed by moving the tip across the surface at a fixed rate (˜0.15 microns / second). The height and width of the lines can also be varied by changing the applied force as in FIG. The nanoscale particle pattern was cured by applying heat (250 ° C., 5 seconds) with a heat gun and verified by reimaging in FIG. 13.

2. Polyol  ink

Another method of preparing nanoparticles is to chemically reduce metal salts in the presence of alcohols or polyols with heat. This method has been reported by Figlarz et al. (US Pat. No. 4,539,041) as a means of making dispersed nanoparticles. This method was improved by Chow et al., Who reported a similar method of forming continuous films. This polyol process for forming nanoparticles for use as ink for nanoscale and microscale conductive patterns can be creatively and advantageously adopted.

Ink ready. The general formula of the metal precursor ink includes an alcohol containing a matrix and a metal salt. After patterning, the salts are converted in-situ into nanoparticles, which coalesce into the metal film with increasing heat. In preliminary experiments, many other metals and metal alloys (summarized in US Pat. Nos. 5,759,230 and 4,539,041) also follow this process, but this process has been demonstrated for metals such as Au, Pt, Pd and Ag.

Polyol  Nanometer Scale Patterns with Ink

Example  One

Nanoscale features of platinum were written using a precursor ink consisting of 10 mg / μL hydrogen hexachloroplatinate (IV) hydroxide dissolved in 20% Millipore water and 80% ethylene glycol. This ink can be written on glass or silicon oxide substrates cleaned using DPN printing techniques. For micron-sized patterns, tipless cantilevers provide optimal control over pattern size and thickness, while for nanoscale patterns, cantilevers with extremely sharp tips (e.g. silicon nitride) on the ends of the flexible cantilever Provide optimal resolution. After deposition, the precursor pattern is converted to metal features by heating with a hot plate or hot air gun. This curing or conversion reaction occurs rapidly (several seconds) at a temperature of about 250 ° C. The thickness of the pattern can be increased by adding ink layers between curing steps. Fig. 10 shows a laminated nanoscale pattern formed on silicon oxide using this ink. A similar method was used to draw micron sized platinum traces on silicon oxide between gold electrodes. Figure 14 shows a 110 micron long line drawn with platinum chloride ink by moving the ink coated cantilever in a direction parallel to its minor axis. After curing, a single layer of ink had a high resistance, but subsequent layers could be added to increase the height of the pattern and thus the conductivity.

Example  2

In another example, platinum features were used to form dot features between micron-sized gold electrodes. As shown in the optical image of FIG. 15, the dots were formed by briefly contacting the coated tip / cantilever assembly to a surface (several seconds) and then withdrawing the tip to leave a drop. The size of the droplets depends on the wettability of the ink on the surface, the loading of the tip and in some cases the tip-substrate holding time.

Example  3

In order to change the viscosity and wettability of the metal salt precursor ink, several different polymers were used as additives. For example, ethylene glycol was replaced with polyethylene glycol as the reducing agent to improve ink properties. Mixtures of two different molecular weight polyethylene glycols are used to obtain particularly useful platinum inks. To prepare this ink, 100 mg of hydrogen hexachloroplatinate (IV) hydroxide was dissolved in 15 microliter aqueous solution containing 30 mg of 300 and 10,000 molecular weight polyethylene glycol each. The ink is well wetted to the glass surface and cures with heat to form a conductive platinum film. For example, Figure 16 shows an example of a single layer platinum trace drawn between chromium electrodes. After curing, the resistance of the 50 micron long traces was 80 ohms and the traces adhered well to the surface during the rinse and scotch tape peel test.

Example  4

Gold has a much lower bulk resistivity than platinum. Thus, similar metal ink precursors of the hydrogen tetrachloroorate (III) trihydroxide series of gold salts have been tested to improve the conductivity of metal traces for applications such as repairing metal traces in thin film transistors. Representative compositions include 100 mg of gold salt in 80% ethylene glycol / 20% water. The gold precursor ink was well wetted with silicon oxide and glass surface during writing and cured in 5-10 seconds at 200 ° C. on a hot plate. The resulting film appeared black on the optical micrograph and consisted of small segregation particles according to AFM images. Single layer traces were typically insulators and did not adhere well to the cleaned silicon oxide substrate. Subsequent layers (about 5) increased the height and diameter of the individual particles to several hundred nanometers, but large interparticle separation resulted in high resistance (hundreds of ohms across the 100 micron long electrode gap). The AFM scan of FIG. 17 shows large gold particles formed after the three layer gold chloride ink was deposited on the silicon oxide between the gold electrodes.

Example  5

Useful inks for forming conductive traces on silicon oxide combine the properties of gold and platinum precursor inks. Therefore, in order to obtain high conductivity of gold and excellent deposition and film adhesion of platinum, gold and platinum-based alloy forming inks have been developed. For example, one composition well suited for patterning methods included 100 mg of platinum and 50 mg of gold dissolved together in 30 microliters of water containing 60 mg of 300 and 10,000 MW polyethylene glycol, respectively. The two layer pattern shown in FIG. 17A drawn on silicon oxide across the 30 micron gap had a resistance of 90 ohms after curing. Six layers of the same alloy ink written with PDMS (polydimethylsiloxane) coated AFM tips between the chromium electrodes provided 32 ohms of resistance after curing and reached a height of 80 nm (FIG. 17B). 17C shows uniform gold-platinum particles in a six layer pattern measured by AFM. In order to further increase the conductivity of the metal traces, the substrates were immersed in silver strengthening solution for 1 hour. Optical and AFM images showed that the silver reinforcement solution formed a silver coating only on the areas already containing gold. This experiment provides additional evidence that the pattern contains gold metal in the fully reduced state. Current-voltage measurements indicate that the resistance decreased to 24 ohms after silver deposition.

Example  6

One way to improve the adhesion of polyol inks to glass surfaces (and many other surfaces) is to add a small amount of epoxy to the ink formulation. For one such ink, 85 mg of hydrogen gold tetrachloride was dissolved in 50 microliters of dimethylformamide. To 3 microliters of this salt solution were added 1 microliter of ethylene glycol and 1 microliter of epoxy mixture. Curing time increases in the presence of gold salts, but the two part epoxy (377 epotec) purchased from Epotek was cured within 1 hour at 120 ° C. in the absence of metal salts and the epoxy (bisphenol-F) purchased from Aldrich Was cured at 150 ° C. in 1 minute. The resulting ink mixture easily migrated to the surface during the standard deposition process but was not very wet with the glass surface. After patterning, heat was used to convert the metal salts into nanoparticles and crosslink the epoxy. The resulting film adhered extremely well to the glass surface and withstood all standard cleaning procedures (water rinse and scotch tape peeling) as well as mechanical polishing. As long as the metal amount of the ink was high enough, the metal traces formed between the gold electrodes had a moderately low resistance. FIG. 18 shows optical micrographs of large gold features on glass prepared using epoxy reinforced ink with curing at 150 ° C. for 2 hours. The resistance of the membrane was 0.3 ohms.

Example  7

In all of the above examples, the micron scale pattern was deposited using the cantilever as the source of ink and the main delivery tool. However, to form submicron sized features using such metal precursor inks, it is useful to use sharp tips on the cantilever end as ink sources and ink delivery tools. One metal ink that is particularly well suited to micron and submicron scale patterning is a variant of the gold ink described above. To prepare the ink, gold chloride (85.5 mg) is dissolved in 50 microliters of dimethylformamide. To this solution is added 1 microliter of ethylene glycol and 0.1 mg of thiotic acid. This ink can be deposited using silicon nitride tips, but the reliability of patterning is improved when PDMS coated tips are used for writing. Writing this ink on a quartz substrate forms features as high as 15 nm, as evidenced by the AFM image of FIG. The precursor ink pattern is cured in an oven at 120 ° C. for 5 minutes and then at 250 ° C. for 10 seconds. Importantly, the pattern shows good stability and withstands water rinses and two piranha solution washes (3: 1 H ₂ SO ₄ / H ₂ O ₂ ) at 120 ° C. for 10 minutes each.

All of the references below are hereby incorporated by reference in their entirety.

Ink and Calm and  Related Additional References

Technology

Patent

Burger, G. Burger, G. Elders, J., Spiering, V. << Apparatus for metered collection and distribution of liquids, methods of making such devices and methods of collecting and dispensing liquids >> PCT / NL01 / 00467 or WO 02/00348.

Seed. Bergard, p. P. Belaubre, B. B. Belier, J.-B. J. B. Pourciel. Devices for active controlled local deposition of at least one biological solution (Systeme de depot de solutions biologiques avec ou sans contact pour la fabrication de biopuces).

PCT / FR03 / 01481 or WO 03/097238 or 0202016.

6,294,401 to Jacobson et al. Nanoparticle-based electrical, chemical and mechanical structures, and methods of manufacturing the same.

No. 6,458,431 to Hill et al. Methods of lithographic deposition of materials containing nanoparticles. Scattered nanoparticles are deposited on the surface and converted to a metal or metal oxide film, and the film is patterned. Used in applications such as diffusion barriers, electrodes, etc.

Deposition is carried out using dipping, spin coating, spraying, dip coating, ink.

The conversion is carried out electromagnetically, photochemically, thermally, in a plasma, in an ion beam, in an electron beam, as a source of energy, but in a hybrid method in which light initiates a thermal reaction rather than a photochemical reaction.

Changing properties in different atmospheres.

6,348,295 to Griffith et al. A method of manufacturing an electromechanical device by thin film deposition and imaging. This patent describes nanoparticle colloidal suspensions for direct write preparation. Nanoparticles can be capped and melted with an insulating shell that can be removed by application of energy (heat). This patent covers electrically active patterns and multilayers. The membranes can be reduced through electromagnetic radiation, laser, heat, low temperature.

Deposition: The particles are applied to the surface via spin coating, by substitution, spraying technique (ink jet), transfer technique (eg microcontact printing) or electrostatic patterning. In the description of the embodiments, these thin films can be deposited using a modified "pull-down bar" mechanism. In this technique, a flat rod or wedge approaches to cover the surface and then passes over a surface with a pool of nanoparticle suspension disposed on the side in the direction of travel. As a result, a thin film is formed on the back side of the bar.

6,103,868 to Health et al. Organically functionalized monodisperse nanocrystals of metals. A comprehensive method for making metal nanoparticles coated with a surfactant is described.

Goldstein 6,645,444. Metal nanocrystals and their synthesis. This patent describes a method for the synthesis of metal nanoparticles involving the reduction of metal-ligand composites in the presence of a solvent.

No. 6,413,790 to Duthaler et al. Preferred method for producing battery circuit elements used to control electronic displays. Ink jet printing of materials for manufacturing display devices and various other soft lithography techniques.

4,539,041 to Piglas et al. The reduction process of a metal compound with a polyol, and the metal powder obtained by this process.

No. 5,759,230 to Chow et al. Nanostructured metal powders and films through alcoholic solvent processes.

Additional Description from Reference 16 ("Conductive Pattern")

The above-mentioned reference 16, which is incorporated by reference in its entirety, is provided below to enable those skilled in the art to practice the invention (patent application "process for making conductive patterns using nanolithography as a patterning tool").

For additional background, many important applications in biotechnology, diagnostics, microelectronics, and nanotechnology require nanostructures of metals, one of the basic types of materials. For example, better microelectronics are needed to provide smaller and faster computer chips and circuit boards, and metals can provide the conductivity needed to complete the circuit. Metals can also be used as catalysts. However, machining of metals can be difficult, and working on nanoscale can make the problem even more difficult. Many methods are limited to the production of micron levels. Many methods are limited by the electrochemical bias or the need for very high temperatures. Moreover, many methods are limited by the physical requirements of the deposition process, such as ink viscosity. There is a need for a better method for fabricating metal nanostructures, in particular by means of providing alignment, film and wire lamination, high resolution and multifunction.

In short, the present invention includes a series of embodiments summarized herein without limiting the scope of the invention. For example, the present invention provides a method of depositing a conductive coating on a substrate in a desired pattern, which method comprises (a) depositing a precursor on the substrate in a desired pattern by nanolithography using a tip coated with the precursor. step; (b) contacting the precursor with a ligand; (c) optionally, applying sufficient energy from the extended radiation source to transfer electrons from the ligand to the precursor to decompose the precursor to form a conductive precipitate in a desired pattern, thus forming a conductive pattern directly on the substrate. do.

The present invention also provides a method of printing a conductive metal on a substrate in a desired pattern, which method comprises: (a) using nanolithography with a tip coated with a precursor to direct the metal precursor and ligand onto the substrate according to the desired pattern. Drawing a drawing; And (b) forming a conductive metal in a desired pattern by decomposing the precursor by applying energy from an extended radiation source, optionally without removing a substantial amount of precursor from the substrate, and without removing a substantial amount of metal from the substrate. It includes a step.

The invention also provides a nanolithography method comprising depositing a metal precursor onto a substrate at a tip to form a nanostructure and then converting the precursor nanostructure to a metal deposit. Deposition can be performed without electrical bias between the tip and the substrate.

The present invention also nanolithography essentially comprising depositing an ink composite comprising a metal precursor as an essential component on a substrate at a nanoscale tip to form a nanostructure, and then converting the nanostructured metal precursor into a metal form. Provide a method. While the basic and novel aspects of the present invention are described throughout this specification, these aspects do not require stamps and resists, do not require electrochemical bias, and are expensive that are not readily available for general laboratories and production facilities. No equipment is required, and no reaction between the substrate and the ink is required. Thus, composites and inks can be formulated and patterned without this limitation.

The present invention also provides a method for printing without electrochemical bias or reaction between the ink and the substrate, which deposits a metal precursor ink composite in the form of microstructures or nanostructures on the substrate at the tip onto the substrate. Forming an array with discrete objects separated from each other by about 1 micron or less, about 500 nm or less, or about 100 nm or less.

The present invention also provides a patterned array comprising discrete nano and / or micro class metal deposits on a substrate and a substrate prepared by the methods according to the invention. The metal deposit can be, for example, rectangular, square, dot or line.

The invention also provides a method using a method comprising, for example, preparing a sensor, a biosensor and a lithography template as well as other applications described herein.

1 of Reference 16 shows AFM data of a palladium structure according to the present invention in Example 1. FIG.

Figure 2 of Reference 16 shows AFM data of a palladium structure according to the present invention in Example 3.

Figure 3 of Reference 16 shows AFM data of a platinum structure according to the present invention in Example 4.

Figure 4 of Reference 16 shows AFM data of a palladium structure according to the present invention in Example 5.

Figure 5 of Reference 16 shows AFM data of a palladium structure according to the present invention in Example 5.

Detailed Description of Reference 16 ("Conductive Pattern")

Reference 16 is provisional application 60 / 405,741 to Crocker et al., Filed Aug. 26, 2002, the entirety of which is incorporated herein by reference, and 60.419,781 to Crocker et al., Filed Oct. 21, 2002. Claim the benefit of favor.

As mentioned above, DPN ^™ and DIP PEN NANOLITHOGRAPHY ^™ are trademarks of nanoinks and are used as appropriate herein (eg, DPN printing or DIP PEN NANOLITHOGRAPHY printing). DPN methods and equipment including NScriptor ^™ that can be used to perform nanolithography according to the present invention are generally available from NanoInk, Inc. (Chicago, Ill.).

While this specification provides guidance to those skilled in the art including references to technical literature for practicing the invention, such references do not constitute an admission that the technical literature is prior art.

Direct write techniques are described, for example, in Direct-Write Technologies for Rapid Prototyping Applications: Sensors, Electronics, and Integrated Power Sources, Ed. by A. Pique and D.B. Chrisey, Academic Press, 2002]. For example, Chapter 10 of Merkin, Demers, and Hong describes nanolithography printing on a sub 100 nanometer long scale, which is incorporated herein by reference (pages 303-312). . Pages 311-312 provide further reference to scanning probe lithography and direct writing methods using patterning compounds transferred from nanoscale tips to a substrate that can guide those skilled in the practice of the present invention. This text also describes the conductive pattern.

Nanolithography and nanofabrication are also described in Marc J. Madou's Fundamentals of Microfabrication, The Science of Miniaturization, 2nd Ed., Which includes metal depositions on pages 344-357.

The present application discloses a number of embodiments for manufacturing conductive patterns using deep pen nanolithography (DPN) printing as a patterning tool. For all embodiments herein, the following documents describing the DPN printing method are incorporated herein by reference and form part of this specification:

(1) Piner et al. Science, 29 January 1999, Vol. 283 pgs. 661-663].

(2) US Provisional Application No. 60 / 115,133, filed January 7, 1999 to Merkin et al.

(3) US Provisional Application No. 60 / 207,713, filed October 4, 1999 by Merkin et al.

(4) United States Patent Application Serial No. 09 / 477,997, filed January 5, 2000 to Merkin et al.

(5) US Provisional Application No. 60 / 207,713, filed May 26, 2000 to Merkin et al.

(6) US Provisional Application No. 60 / 207,711, filed May 26, 2000 to Merkin et al.

(7) United States Application No. 09 / 866,533, filed May 24, 2001, to Merkin et al.

(8) US Patent Publication No. 2002/0063212, published May 30, 2002 by Merkin et al.

The present invention is not limited to printing using only one tip; rather, a number of tips may be used, for example, US Patent Publication No. 2003 to Liu et al., Published January 30, 2003. / 0022470 ("Parallel Individually Accessible Probes for Nanolithography").

In particular, previous applications 09 / 866,533 filed May 24, 2001 (references 7 and 8 above, 2002/0063212 published May 30, 2002) include, for example, a background (page 1-13), Summary (page 3-4), Brief Description of Drawings (page 4-10), Use of Scanning Probe Microscope Tips (page 10-12), Substrate (page 12-13), Patterning Compound (page 13-17), for example, methods of implementation involving tip coating (pages 18-20), instruments involving nanoplotters (pages 20-24), use of multiple layers and related printing and lithography methods (pages 24-26) , Resolutions (page 26-27), arrays and combination arrays (page 27-30), software and calibration (pages 30-35, 68-70), kits and other items including tips coated with hydrophobic compounds (page 35) -37), examples that cover various embodiments including examples (pages 38-67), corresponding claims and abstracts (pages 71-82), and Figures 1-28. The contact nanolithography printing background and procedure are described in detail. This disclosure is not repeated herein and need not be repeated, but is incorporated by reference in its entirety.

In addition, US Patent Publication No. 2002 0122873 to Merkin et al., Published September 5, 2002, is not repeated herein and need not be repeated, but is incorporated by reference in its entirety. This publication includes, for example, the use of tips having external openings and internal cavities, and the use of electrical, mechanical and chemical driving forces to transfer ink (deposition compounds) to a substrate. One method includes aperture pen nanolithography, in which the speed and range of movement of the deposition compound through the aperture is controlled by the driving force. This publication also describes coated tips, patterns, substrates, inks, patterning compounds, deposition compounds, multiple tip nanolithography, multiple deposition compounds, and arrays.

Nanolithography is also described in the following references:

(a) B.W. Maynor et al. Langmuir, 17, 2575-2578 ("Au 'ink' for AFM 'Dip-Pen' Nanolithography") describes the formation of gold nanostructures by surface induced reduction of metal ions. However, this method involves careful selection of a suitable gold precursor and a substrate surface that reacts with gold, which limits the process and is not necessary in the present invention.

(b) [Y. Li et al., J. Am. Chem. Soc., 2001, 123, 2105-2106 ("Electrochemical AFM 'Dip-Pen' Nanolithography") describe the deposition of platinum metals. However, this method involves the use of an external electrochemical bias between the tip and the substrate, which limits the process and is not necessary in the present invention.

In the DPN printing process, the ink is transferred to the substrate. The substrate may be flat, rough, curved or have surface features. The substrate may be patterned in advance. Fixation of the ink on the substrate is possible by chemical adsorption and / or covalent bonding. The transferred ink can be used directly as part of the manufacturing design, if desired, or indirectly as a template for further manufacturing. For example, proteins may be patterned directly on a substrate by DPN printing, or template compounds used to bind proteins may be patterned. The benefits and applications of DPN printing vary and are described in the references above. For example, a composite structure with high resolution and good registration can be achieved. Structures with a line width, cross section and circumference of less than 1 micron, in particular less than 100 nm, in particular less than 50 nm can be achieved. In short, DPN printing is a potential nanofabrication / nanolithography technology that enables nanometer-level fabrication and lithography with superior control and versatility. Nanofabrication and nanolithography of this type can be difficult to achieve with many techniques that are more suitable for micron scale operations. DPN printing can also be used to prepare microscale structures if desired, but nanostructures are preferred.

The tip may be a nanoclass tip. The tip may be a scanning probe microscope tip that includes an AFM tip. The tip may or may not have a cavity. The ink passes through the center of the cavity tip to coat the end of the tip. The tip can be adapted to facilitate printing of the precursor ink. In general, it is desirable that the tip does not react with the ink and can be used for a long time.

Patterns deposited by nanolithography are not particularly limited by the shape of the pattern. Common patterns include dots and lines and arrays thereof. The height of the pattern can be for example about 10 nm or less, in particular about 5 nm or less. When the line is patterned, the line can be, for example, about 1 micron or less wide, especially about 500 nm or less wide, in particular about 100 nm or less wide. When the dot is patterned, the dot can be, for example, a diameter of about 1 micron or less, in particular a diameter of about 500 nm or less, in particular a diameter of about 100 nm or less.

Nanolithography is preferably performed to form nanostructures, but micron scale structures may also be of interest. For example, the experiments used to pattern structures of 1-10 square microns, such as rectangles, squares, dots, or lines, can also be used to design experiments for smaller nanostructures.

In another embodiment, a conductive pattern comprising a nanoscale pattern is formed using DPN printing using the following steps:

1) depositing a precursor, such as a metal salt, onto the substrate in a desired pattern using, for example, a coated tip.

2) applying an appropriate ligand onto the substrate, for example the ligand comprises a donor atom such as nitrogen, phosphorus or sulfur.

3) applying sufficient energy to transfer electrons from the ligand to the precursor, for example by radiant heat, to decompose the precursor to form a precipitate, for example a metal.

Metal patterning processes and chemistries include (1) US Pat. No. 5,980,998 to Sharma et al., Issued November 9, 1999, and (2) Narang, incorporated herein by reference. US Pat. No. 6,146,716, issued Nov. 14, 2000. However, these references neither disclose nor suggest the use of deep pen nanolithography printing or other nanolithography for deposition, nor do they disclose or suggest the benefits arising from DPN printing. Rather, they disclose the use of conventional printing methods using dispensers including reservoirs and applicators. The chemistry and patterning disclosed in Shama's 5,980,998 patent is modified in an unexpected manner, which generally yields unexpected results to include DPN printing as a patterning method and the DPN printing process uses the chemistry disclosed in Shama's 5,980,998 patent. Embodiments are disclosed that are modified in an unexpected manner with unexpected results to include.

Ink solutions herein are generally intended to include solvents and solutes. The solvent may be any material capable of solvating the solute, but is generally intended to include materials such as water, various alcohols, etc., which are inexpensive, readily available, and relatively non-toxic. Solutes are generally intended to include at least two components that chemically react with each other under the influence of an energy source such that a metal or other substance precipitates out of solution. In a preferred embodiment, one component of the solute comprises a salt and the other component of the solute comprises a suitable ligand. The term "salt" as used herein refers to any combination of acid (A) and base (B). Examples are metal salts such as copper formate, acetate, acrylate, thiocyanate, and iodide. Other examples are nonmetal salts such as ammonium formate and ammonium acrylate.

The various components of the solution can be deposited on the substrate simultaneously, sequentially or in a combination of the two. Thus, salts are intended to be deposited simultaneously with the ligand or deposited separately from the ligand. It is also intended that the solvent itself can include or contribute to one or more embodiments of salts or ligands.

As used herein, the term "ligand" (L) may be thermally activated to substitute one or more embodiments of the salt in a redox reaction such that AB + L <-> AL + B or AB + L <-> A + BL. It refers to any substance that can be. In the process intended herein, preferred ligands are amorphous, leave no nonmetallic residues, and are stable under normal atmospheric conditions. More preferred ligands may participate in redox reactions with certain salts used at suitable temperatures, generally considered to be less than about 300 ° C.

Preferred ligand groups are nitrogen donors, for example comprising cyclohexylamine. However, many other nitrogen donors and mixtures thereof may also be used. Examples are 3-picoline, lutidine, quinoline and isoquinoline, cyclopentylamine, cyclohexylamine, cycloheptylamine, cyclooctylamine and the like. However, these are only a few examples and many other aliphatic first, second and third amines and / or aromatic nitrogen donors may also be used.

The intended solution may include other compounds in addition to salts and ligands. For example, a mixture of copper (II) formate in a nitrogen donor solvent, with or without water and alcohol, can be used to facilitate migration from the tip to the substrate. Small amounts of solvent-based polymers or surfactants may also be useful additives for adjusting the flowability of the precursor solution to facilitate migration from the tip to the substrate and to impart better film formation properties. On the other hand, high boiling point solvents and / or additives such as triethylphosphate, Triton X100, glycerol and the like are known as Kapton ^™ . Or it is desirable to avoid, as it tends to contaminate the film resulting from incomplete pyrolysis on a temperature sensitive substrate such as paper. Moreover, it is valuable to improve adhesion of the deposition material to the substrate as a function of treating the substrate with the binder to modify the hydrophobicity or hydrophilicity of the substrate surface of the binder.

If the salt comprises a metal, all metals are intended. Preferred metals include conductive elements such as copper, silver and gold, but also semiconductors such as silicon and germanium. For some purposes, especially for the production of catalysts, it is intended that metals such as cadmium, chromium, cobalt, iron, lead, manganese, nickel, platinum, palladium, rhodium, silver, tin, titanium, zinc and the like can be used. . The term "metal" as used herein includes alloys, metal / metal composites, metal ceramic composites, metal polymer composites as well as other metal composites.

The substrate may comprise substantially any material from which a compound may be deposited thereon. For example, intended substrates include metals and nonmetals, conductors and insulators, stretched and non-stretched materials, absorbing and non-absorbing materials, flat and curved materials, textile and nonwoven materials, solid and hollow materials, and large and small objects. Include. Particularly preferred substrates are circuit boards, paper, glass and metal objects. From another perspective, a wide range of intended substrates provide some indication of the range of intended purposes to which the teachings of the present invention may be advantageously applied. Thus, the methods and apparatus taught herein include multichip modules, PCMCIA cards, printed circuit boards, silicon wafers, secure printing, decorative printing, catalysts, electrostatic shielding, hydrogen pass-through membranes, gradient functional materials, nanomaterial production, battery electrodes And fuel cell electrodes, actuators, electrical contacts, capacitors, and the like. This method and apparatus can be used as sensors and biosensors. This method and apparatus can be used to prepare a template for further lithography, such as imprint nanolithography. It is particularly interesting to connect nanowires and nanotubes using this method.

Thus, the substrate may or may not be installed or partly installed, in particular, in electronic devices, such as computers, disk drives or other data processing or storage devices, telephones or other communication devices, and batteries, capacitors, chargers, controllers or other energy storage related devices. It is intended to represent any suitable substrate, including circuit boards, which may constitute.

Suitable energy sources intended herein include any source capable of causing the desired chemical reaction without causing excessive damage to the substrate or coating. Thus, particularly preferred energy sources are radiation and convective heat sources, in particular including infrared lamps and hot blowers. Other suitable energy sources include electron beams and radiating elements of non-infrared wavelengths including x-rays, gamma rays and ultraviolet rays. Another suitable energy source includes a vibration source such as a microwave transmitter. It should also be understood that various energy sources may be applied in various ways. In a preferred embodiment, the energy source is directed to the precursor / ligand deposited on the substrate. However, in other embodiments, for example, a heated ligand may be applied to a cold precursor or a heated precursor may be applied to a cold ligand.

Many advantages can be recognized from the present invention, including, for example, flat surfaces, good coating adhesion and control of coating thickness. Another advantage of the various embodiments of the present invention is that the coating can be deposited with at least 80% by weight purity. In a more preferred embodiment, the purity of the metal or other material intended to be included in the coating is at least 90%, in even more preferred embodiments the purity is at least 95% and in most preferred embodiments the purity is at least 97%.

Another advantage of the various embodiments of the present invention is that the coating can be deposited leaving very little waste. In a preferred embodiment, at least 80% by weight of the material deposited on the substrate is used to form the desired pattern. For example, when copper (II) formate is used to create a copper circuit, at least 80% of the copper deposited on the substrate can be used to form the desired pattern, and less than 20% of the copper is "waste". Is removed as. In a more preferred embodiment, the waste is less than 10%, in even more preferred embodiments the waste is less than 5% and in the most preferred embodiment the waste is less than 3%.

Another advantage of various embodiments of the present invention is low temperature operation. For example, the metal may be in a desired pattern at a temperature below about 150 ° C., preferably below about 100 ° C., more preferably below about 75 ° C., most preferably at room temperature (25-30 ° C.). Can be deposited. The redox or “cure” step may also be carried out at relatively low temperatures of about 100 ° C. or less, more preferably about 75 ° C. or less, even about 50 ° C. or so. Redox reactions below about 50 ° C. tend to be too slow for most applications, but much lower temperatures are possible. These ranges allow the precursor solution to be prepared at room temperature, the deposition being performed at room temperature, and the decomposition being achieved using relatively low heat, for example from a heat gun, in a room temperature environment.

The prior art describes additional methods and composites that can be used to practice the present invention. For example, US Pat. No. 5,894,038 (April 13, 1999) to Shama et al., Incorporated herein by reference in its entirety, (1) preparing a solution of palladium precursor, (2) preparing a palladium precursor Disclosing a direct deposition of palladium comprising the process of forming a palladium layer on a substrate, the method comprising applying to the surface of the substrate and (3) heating the palladium precursor to decompose the palladium precursor. This method may also be suitable for performing nanolithography according to the present invention.

In addition, US Pat. No. 5,846,615 (December 8, 1998) to Shama et al., Incorporated herein by reference in its entirety, discloses the decomposition of gold precursors for forming gold layers on substrates. This method may also be suitable for performing nanolithography according to the present invention.

Moreover, US Pat. No. 4,933,204, incorporated herein by reference in its entirety, discloses the decomposition of gold precursors to form gold features. This method may also be suitable for performing nanolithography according to the present invention.

Moreover, US Pat. No. 6,548,122 (April 15, 2003) to Shama et al., Incorporated herein by reference in its entirety, discloses the use of gold and silver precursors as well as copper (II) formate precursors.

Although the present invention is believed to be broad in scope, the following inks or patterning compounds, namely copper formate or copper acetate; Silver sulfate; Silver nitrate; Silver tetrafluoroborate; Palladium chloride, acetate, and acetylacetonate; Hexachloroplatinic (IV) acid; Ammonium iron citrate; Carboxylates, (pseudo) halides, sulfates, and nitrates of zinc, nickel, cadmium, titanium, cobalt, lead, iron, and tin; Metalcarbonyl composites including chromium hexacarbonyl; Amine bases including cyclohexylamine, 3-picolin, (iso) quinoline, cyclopentylamine, dimethylsulfoxide, dimethylformamide, formamide, ethylene diamine; Polymers comprising poly (ethylene oxide), poly (methylmethacrylate), poly (vinylcarbazole) and poly (acrylamide) are of particular interest in the present invention.

For example, in a preferred embodiment, the deposition can be performed using an aqueous solution as an ink, the solution comprising water, a metal salt and a water soluble polymer such as a polyalkylene oxide polymer having a molecular weight of about 50,000 or less. The aqueous solution may also be useful as a carrier for the reducing agent. For example, 10% polyethylene oxide (MW 10,000) via DPN printing on amino silanized glass and subsequent reduction to palladium metal using a reducing agent such as, for example, a 0.03 M aqueous solution of dimethylamine: borane complex (DMAB). Deposition of disodium palladium chloride in water with) may be carried out (Schott Glass). The concentration of the reducing agent can be varied to determine the best condition of the reduction. Nuclear micrographs of the pattern can be obtained before and after reduction. AFM imaging can be performed using the tip or other tip used to deposit the structure. If another tip is used, the image may be better, especially if the tip is selected or suitable for imaging rather than deposition. In general, polymers commercially used in printing inks can be used in the present invention.

In another preferred embodiment, palladium acetylacetonate (Pd (acac)) via DPN printing on an oxidized silicon substrate and subsequent reduction by (1) liquid reducing agent such as formamide and (2) application of heat to the patterned surface Nanolithography deposition may be performed. Another system is palladium acetate in DMF solvent. Prior to patterning and reduction, Pd (acac) may be dissolved in an organic solvent including a halogenated solvent such as chloroform to form an ink for use in coating a solid tip or through a hollow tip. For example, a heat treatment comprising a temperature of about 100 ° C. to about 300 ° C. or about 150 ° C. may be sufficient to effect the reduction. Heating time, temperature and ambient conditions can be adjusted to achieve the desired pattern. Generally a heating time of 1-5 minutes at 150 ° C. can achieve the desired result. The stability of the deposited pattern can be checked by solvent rinsing and the experimental conditions can be altered to improve the stability. Nanolithographic deposition experimental parameters, including the substrate and ink composite, can also be modified to provide better resolution. AFM micrographs, including the use of height scan analysis of patterns, can be obtained before reduction and after application of heat. Imaging parameters can be changed to improve image resolution.

In some cases, a tip, such as a gold coated tip, may promote the reduction of metal salts directly on the cantilever. The tip composite can be modified to prevent this. For example, aluminum coated probes may be useful to prevent reduction on such tips. In general, the tip is selected and suitable for long term use, and it is desirable to avoid catalysis with the ink.

Reduction of the nanolithographic patterned metal salt can also be carried out by gas phase reduction, not by liquid phase reduction, in which the reducing agent turns into vapor form and passes over the patterned surface. If necessary, the reducing agent can be heated to a vapor state using a heater known in the art. In some cases, this type of treatment can improve the preservation of the original pattern during reduction.

In a preferred embodiment, deposition on a silver salt emulsion consisting of ferric ammonium chloride, tartaric acid, silver nitrate and water can be carried out on the amino silanated glass substrate through development by DPN printing followed by light reduction under UV lamp. have. AFM imaging can be performed to show the pattern.

In another preferred embodiment, the reducing step can be performed using sufficient heat and sufficient time to reduce the metal salt without using a reducing agent. For example, a temperature of about 400 ° C. or less or a temperature of about 200 ° C. or less may be used. One skilled in the art can select and experiment appropriately based on the given ink system and pattern.

Deposition methods according to the invention also include one or more predeposition steps, one or more probe cleaning or chemical modification steps to improve ink coating; And one or more deposition steps that may utilize deep pen nanolithography printing techniques; It may comprise one or more post deposition steps including a cleaning step and an inspection step.

Pre-deposition substrate surface treatment steps include but are not limited to (no specific order):

(1) Plasma, UV or ozone cleaning, washing, drying, blowing drying

(2) chemical cleaning such as, for example, pyranha cleaning, basic etching (eg hydrogen peroxide and ammonium hydroxide)

(3) chemical or physical alteration of the substrate to enhance ink transfer or adhesion, or covalent alteration (e.g., base treatment to provide a charged surface on silicon oxide, silanization with amino or mercapto silaning agents, Polymers with chemically reactive functional groups)

(4) protection against side effects of subsequent process steps (coating of resist or thin film)

(5) optical microscope (eg AIMS), electron microscope (eg SEM) or imaging (eg EDS, AES, XPS), ion imaging (eg TOF SSIMS) or scanning probe imaging (Eg, AFM, AC AFM, NSOM, EFM ...), inspection of the substrate using techniques derived from any of the steps described below in the paragraphs after deposition, and combinations thereof.

Probe cleaning or modification steps include, but are not limited to, no specific order:

(a) Plasma cleaning, washing, drying, blowing drying

(b) chemical cleaning such as piranha cleaning, basic etching (eg hydrogen peroxide and ammonium hydroxide);

(c) chemical or physical alterations to enhance ink coating, adhesion or transfer (e.g., base treatment to provide a charged surface of silicon nitride tips, silanization with amino or mercapto silanizing agents, small molecules or poly Non-covalent modifications with polymeric agents such as (ethylene glycol). Such modifications include those that increase the loading of ink on the tip by increasing the porosity or increasing the surface area available for ink delivery.

Deposition Steps:

Deposition steps include, but are not limited to, deposition of one or more inks, for example by DPN printing or deposition using one or more probes. Possible inks include, but are not limited to, precursors, compounds that form the bulk of the final pattern, catalysts, solvents, small molecule or polymer carriers, host matrix materials, or sacrificial reducing agents, and mixtures of these materials. They can be deposited as thin films or as thick multilayers (formed by multiple deposition steps) with or without a change in chemical composition from layer to layer.

Post-deposition steps include, but are not limited to (no specific order):

(1) For example, heating a substrate using a heating lamp, a high temperature blower, or a hot plate

(2) Irradiation of the substrate using electromagnetic radiation (eg IR, visible and UV light) or charged particles (eg ions emitted from electrons, guns or plasma sources). This process can be carried out with or without photosensitizers in air, vacuum or in solution.

(3) soaking in one or more solutions of the patterned substrate

(4) electrochemical reduction

(5) chemical reduction

(6) exposure of the patterned substrate to vapor or gas;

(7) Ultrasonic decomposition of the patterned substrate, as well as all nanoscale local equivalents of the foregoing steps. Where available, the source of energy and / or the composition of matter is provided by one or more probes, which may or may not be the same as the DPN probe. This includes, but is not limited to:

(a) local heating of the deposited material or surrounding substrate

(b) Local investigation of the deposited material or surrounding substrate and all combinations thereof.

All or some of the steps may be repeated several times.

The metal nanostructures may be in the form of conductive nanoscale grids that may include nanowires. For example, a crossbar structure can be formed. Metal layers may be formed on top of each other. The structures can be included to integrate nanoscale conductive patterns with micro and macro test methods. Resistors, capacitors, electrodes and inductors can be used as needed to form a circuit. Semiconductors and transistors can be used as needed. Formation of the multilayer can be performed to increase the height of the structure. Different metals may form different layers of the multilayer. The method of the invention can be used to electrically connect the electrodes. For example, in sensor applications, metal deposits can have a resistivity that changes when the analyte is bound to the structure. For example, in biosensor applications, antibody-antigens, DNA hybridization, protein adsorption and other molecular recognition events can be used to trigger a change in resistivity. The method of the present invention can also be used for barcode applications.

For example, US Pat. No. 6,579,742 to Chen describes nanolithography structures formed by imprinting for nanocomputing and microelectronics applications. However, imprinting can cause a mold sticking effect. Nanocomputing applications and structures of US Pat. No. 6,579,742 can be performed using the nanolithography methods described herein, which are incorporated by reference in their entirety.

Substrates may be, for example, prototype substrates, as described in US Pat. This allows the conductivity of the printed substrate to be inspected by the microscopic method.

Non-limiting embodiments of Reference 16 are described below.

Of reference 16 Examples

General approach:

This method provides for direct deposition of metal nanopatterns. Oxidative and reducing compounds can be mixed together, applied to the tip, and deposited at selected locations on the substrate by DPN printing or deposition. The ink mixture can then be heated (by heating the entire substrate or by local probe induction heating). In particular, metal salts and organic ligand cocktails can be used. Representative ink formulations may include metal salts (eg carboxylates, nitrates or halides) with appropriate organic Lewis bases or ligands (amines, phosphines). Additives that change the solubility, reactivity or flowability of the ink (small molecules such as ethylene glycol, polyethylene oxide, PMMA, polymers such as polyvinylcarbazole, etc.) may also be used. After deposition of the ink mixture, appropriate heating (eg, 40-200 ° C.) in an atmospheric or inert environment assists in the disproportionation of salts to form metal precipitates and volatile organics. This approach enables the deposition of various metals or metal oxides, including, for example, copper, under mild conditions with very little organic contamination (e.g., the complete disclosure of which is specifically incorporated herein by reference for deposition materials). US Pat. No. 5,980,998 to Shama et al.). Potential risks may arise if the ligand evaporates from the patterned substrate before the reaction occurs. In this case, the salt patterned substrate may be exposed to the ligand in the second step before heating.

Deposition experiments and AFM imaging can be performed using CP study AFM (Veeco Instruments, Santa Barbara, Calif.) Or NSCRIPTOR (nanoink). For both deposition and imaging, contact modes can be used, including topography or lateral force modes.

Example 1 of Reference 16

One particular example of the use of this method includes palladium acetylacetonate (1 mg / microliter; generally a nearly saturated ink solution is preferred) dissolved in chloroform on silicon oxide, glass or amino silanated glass. DPN printing or deposition was used for patterning. After patterning the dots, a drop of formamide (1 microliter) was placed on a horizontal substrate and heated to 150 ° C. for 2 minutes. The resulting metal pattern was stable to solvent rinsing (including water, alcohol and other nonpolar organics), while the salt pattern before reduction was removed by solvent rinsing. 1 shows AFM images and height scans of patterns before (FIG. 1A) and after (FIG. 1B and FIG. 1C) treatment with formamide and heat.

Example 2 in Reference 16

Palladium nano patterns were deposited by DPN printing and metallized by vapor reduction. DPN inks made of palladium acetate in dimethylformamide were patterned on silicon oxide using DPN technology. The DPN pen used was a gold coated silicon nitride probe. This process also works well for aluminum coated DPN probes because Al coating does not promote the reduction of metal salts directly on the cantilever as in gold coated probes. Prior to patterning, the silicon / silicon oxide wafers were cleaned by sonication for 5 minutes in millipore water. The patterned substrate was placed vertically in a conical polyethylene tube and 10 microliters of formamide liquid was placed at the bottom of the tube. The tube was placed on a heating block and heated at 80 ° C. for 30 minutes, causing vapor to reduce the metal precursor. This method is useful because it protects the metal pattern on the substrate. The resulting metal structure withstands solvent rinsing and other common cleaning methods.

Example 3 in Reference 16

Palladium nanopatterns deposited by DPN were metallized by chemical reduction. DPN inks made of disodium palladium chloride in water with 10% polyethylene oxide (MW 10,000) were patterned onto amino silanized glass (short glass company) using DPN technology. The patterned substrate was exposed to a solution of 0.03 M aqueous solution of dimethylamine: borane complex (DMAB) to cause reduction of the metal precursor to the conductive metal. The resulting metal structure withstands solvent rinsing. 2 shows AFM images and height scans of patterns before (2a) and after (2b, 2c) DMAB processing.

Example 4 in Reference 16

Platinum nanopatterns deposited by DPN were metallized by chemical reduction. DPN inks made of platinum tetrachloride in water were patterned onto amino silanated glass (short glass company) using DPN technology. The patterned substrate was exposed to a solution of 0.03 M aqueous solution of dimethylamine: borane complex (DMAB) to cause reduction of the metal precursor to the conductive metal. Reduction occurs within a few seconds after soaking. The resulting metal structure withstands solvent rinsing. 3 shows an AFM height scan of platinum nanostructures deposited by DPN and reduced by DMAB.

Example 5 in Reference 16

Palladium pattern was deposited by DPN. DPN inks made of palladium acetate in dimethylformamide were patterned on silicon oxide using DPN technology. Prior to patterning, the substrate was washed with piranha solution at 80 ° C. for 15 minutes. After patterning, the substrate was heated using a hot plate in air for at least 1 minute. After heating the pattern was imaged by AFM. The resulting metal structure exhibits high topography and withstands solvent rinsing and other common cleaning methods. 4 and 5 show the desired structural design (left drawing), the actual pattern before reduction (center drawing) and the actual pattern after heat reduction (right drawing). Imaging of these patterns, in particular already reduced patterns, can be improved, for example, by using clean tips that are not used for deposition.

In sum, in reference 16, nanolithographic deposition of metal nanostructures is provided using coated tips for use in microelectronics, catalysts, and diagnostics. The AFM tip can be coated with a metal precursor and the precursor can be patterned on the substrate. The patterned precursor can be converted to a metal state by the application of heat. This concludes the section on "Additional description from Reference 16 (" Conductive Pattern ").

Additional embodiments

The following describes additional examples that further illustrate and enable the present invention, particularly with respect to alternative ink formulations, alternative substrates that may be patterned. Multilayer patterning, delivery of ink to cantilevers using microfluidic reservoirs, and repair of actual TFT substrates have also been demonstrated.

Example  8: ink formulation

Various ink compositions can be written directly by contacting the cantilever. In addition to the polyol and gold nanoparticle / mesitylene inks described above, the following ink formulations have been successfully deposited using CMD:

Ink Composite # 1: Mesitylene Of Decanol  Gold nanoparticles in mixture

The gold nanoparticle inks described in the above examples were improved by the addition of alcohols, for example decanol CH ₃ (CH ₂ ) ₉ OH. The addition of decanol improves the wettability of the hydrophilic substrate and, in particular, prevents the dropping of deposited inks that form discrete (non-conductive) lines on the hydrophilic substrate. This ink composite was prepared by dissolving 1 mg of hexaneetholol capped gold nanoparticles in 1.5 microliters of thiotic acid dissolved in mesitylene (1 mg / mL) and 0.3 microliters of decanol in general. The ink was converted to a low resistivity metal form by high temperature curing at 250-300 ° C. for 7 minutes followed by low temperature curing at 120 ° C. for 60 minutes.

Ink Composite # 2: 1,3,5- Triethylbenzene  Gold nanoparticles within

The gold nanoparticle inks described above were further improved by replacing mesitylene and decanol with 1,3,5-triethylbenzene (1,3,5-TEB), a solvent with a higher boiling point than mesitylene. Solvent replacement increases the lifespan of inks, such as the decanol-based inks described above (due to less drying), and eventually between the decanol-rich state and the mesitylene-rich state, which leads to nanoparticle precipitation and loss of useful metal content. Prevent state separation.

Ink Composite # 3: Commercial Silver Nanoparticle Inks

Commercial silver paste (Nanopaste NPS-J, http://www.harima.co.jp, available from Harima Chemicals, Japan) was used as ink for flat panel display repair. The silver paste contains mono dispersed nano particles produced by gas evaporation and protected by a dispersant. The average nanoparticle diameter is about 7 nm. When each nanoparticle is covered with a dispersant, the ink behaves almost like a liquid even at high metal contents. Therefore, it may be necessary to concentrate this ink in advance (by evaporation of the solvent in the air) to reach the optimum viscosity. Circuit formation through printing, dispersing and injection of this ink is known in the art. The sintering temperature is less than 200 degreeC. Similar commercial inks including silver, gold (Harima NPG-J) or other types of nanoparticles can also be used.

Example  9: of different inks on different substrates composure

20, 21, 22 and 39 show successful deposition on various substrates of the ink described in Example 8. For example, FIG. 20 shows direct writing of silver lines on silicon nitride substrates using Harima silver nanoparticle inks (composite # 3). Changes in line width and quality observed are the result of an increase in viscosity (increase in concentration) of the ink over time. Over time, the ink becomes too viscous to form continuous lines. All lines were drawn at the same cantilever speed for the substrate. The streaks observed are the product of the stationary and progressive motion of the high precision stage used in this experiment. Figure 21 shows the deposition of the same ink on a glass substrate. Figure 22 shows deposition and low temperature cure of commercial silver nanoparticle inks on glass substrates coated with a chromium thin film. Laser ablation was used to form grooves in the chromium film to expose the lower glass substrate (center of the image). Two lines were then drawn on each side and across the gap of the laser removed gap on the chromium film using a tipless cantilever. Deposition on the chromium film itself was successful, but not across the gap, because in this case the glass substrate remaining after laser removal was particularly rough (> 1 micron. Higher than the deposited film). Figure 39 shows the deposition of Ink Composite # 1 on chromium and glass, and Figure 30 (described below) shows the deposition of gold nanoparticles / 1,3,5-TEB ink.

Example  10: Preparation of Multilayer Pattern

Figure 23 shows the preparation of a multilayer line (up to three layers) using a tipless cantilever coated with gold nanoparticles / mesitylene ink described above. The first layer was deposited on the substrate. After reloading the ink, the cantilever was relocated to the beginning of the first layer line and used to draw the second layer directly on top of the first layer. Note that because the amount deposited is small, the solvent in the first layer dries fast enough to allow drawing of the second layer without the need for an intermediate thermal curing step. The same process was repeated to form a third layer line by depositing a third layer. This process enables the production of thicker lines with greater conductivity and improves line continuity. Line enlargement was also observed. However, it is believed that part of the line magnification is the result of the limitations of the existing XY stage. Substitution with more repeatable stages results in narrower lines.

Example  11: Cantilever  Ink delivery

Figure 24 shows an ink coating of a tipless cantilever (with or without slits) by soaking into a microfabrication reservoir. In this experiment, a microfabricated cantilever was mounted on a scanning head of an NSCRIPTOR instrument (Nano Ink, Inc., Illinois, Chicago), an ink bottle made of silicon microfabricated with the aid of a XY motor stage and a planar video microscope integrated into the instrument. Placed on the chip. The manufacture of such ink bottle chips, which is generally used to deliver ink to tips for dip-pen nanolithography printing, is described in US Pat. No. 10 / 705,776, et al. The ink bottle contains a micro flow millimeter scale reservoir capable of containing ink using a pipette. The cantilever was contained in the ink pool in one of the reservoirs described above (bottom of the image). Note the meniscus around the cantilever in image B. The process is easily automated using the appropriate (Z axis) placement device and software.

Example  12: actual TFT LCD  Repair of samples

25 shows repair of a thin film transistor (TFT) flat panel display. Holes were formed in the insulating layer (silicon nitride) to protect each side of the defect in the conductive traces forming the electronic circuit on the flat panel display using laser ablation. Lines were drawn between these holes using gold nanoparticle ink and then cured to form an electrical bridge between the left and right portions of the trace to repair the bond.

Example 13: Integration Slit  Or with micro flow channels Cantilever  Used composure

Figure 26 is a schematic diagram of a tipless cantilever with ink storage slits or channels. This cantilever can store more ink volume with each dip, which yields better uniformity through the length of the line, increased line height, better conductivity and better writing capability through higher steps. Figure 27 shows four additional designs of a tipless slit cantilever, which may be triangular or square, and may include enlargements that function as reservoirs for fluid storage. The manufacturing technique can be adapted from the methods for the production of AFM cantilevers known in the art. In short, a silicon nitride film is deposited on the sacrificial silicon substrate via CVD. A portion of the silicon nitride is then patterned and then etched to form cantilevers and slits. The bottom silicon can be partially anisotropically etched to free the cantilever. Alternatively, the silicon nitride layer can be bonded to a Pyrex glass wafer and the silicon substrate is etched entirely. The wafer is then diced to provide a chip with a tipless slit cantilever at the end. The cantilever can optionally be coated with a thin layer of reflective metal. The metal coating should be carefully chosen so that it does not react with or affect the ink. Figures 28 and 29 show ink composite # 3 (silver nanoparticles) on a glass substrate and across the gap between the patterned gold electrodes on the glass substrate, prepared by a slit silicon nitride cantilever (blueprint of Figure 26). ) To indicate actual deposition. The resistance between the two gold electrodes in image B was about 100 ohms after thermal curing. Note that the ink deposited directly on top of the gold electrodes becomes invisible after hot ray curing, which is a possible result of alloying or dewetting during curing. 30 demonstrates the deposition of gold nanoparticles / 1,3,5-TEB ink composite # 2 using the same type of cantilever.

Further embodiments

The following describes additional embodiments, particularly related to instruments and methods for repairing flat panel displays.

Embodiment 3: Cantilever  Micro composure  And methods for repairing flat panel displays using laser and laser curing

The present invention further provides a mechanism for repairing gaps in open traces on flat panel display substrates and similar devices, comprising: (1) a cantilever (or microbrush) suitable for containing ink; (2) cantilever holding and placing means adapted to contact and move the cantilever on the surface of the flat panel display substrate to pattern the ink on the substrate in the form of a repair patch; (3) an ink supply mechanism for supplying the ink to the cantilever; (4) Optionally, a curing system suitable for converting the deposited material into a low resistivity form suitable for electrical conduction. The curing system may include a laser and its focusing optics. The cantilever placement means includes: (1) a nanometer resolution stage for controlling the movement of the microbrush along the X, Y, and Z axes; (2) a coarse long range Z stage suitable for contacting the microbrush to the substrate; (3) a rotating stage capable of placing the microbrush at any angle with respect to a Z axis; (4) Optionally, cantilever contact detection means may be included.

When the cantilever or cantilever element has at least a partially reflective coating, the contact detection and cantilever deflection measuring means are (1) computing suitable for measuring the brightness of the video camera, its associated optics, the light source and the light reflected by at least a portion of the cantilever. Way; (2) laser reflection sensors; And (3) a confocal distance measurement system.

In a preferred embodiment, the present invention provides a mechanism suitable for repairing other substantially flat circuits such as flat panel displays and printed circuit boards. This organization may include some or all of the following:

(1) (sub) micrometer wide cantilever

(2) Micro / nanometer scale XYZ stages providing fine movement of the cantilever

(3) laser to cure the deposited material (ink)

(4) Ink supply mechanism for supplying the material (ink) to the micro cantilever before the touchdown operation

(5) Large travel Z stage mover that can provide coarse Z travel for ink supply

(6) a rotating stage capable of positioning the cantilever at any angle with respect to the Z axis.

Figure 31 shows a first design of this instrument for monitoring the brightness of the cantilever through video imaging to detect the touchdown of the cantilever to the surface. In this embodiment, the task of detecting the exact height that the microbrush or cantilever contacts the substrate is by computer monitoring of the video image area corresponding to the cantilever for a change in brightness as the nanometer scale XYZ stage moves the cantilever downward. Is achieved. At the time of contact, a large change in brightness occurs with a sensitivity sufficient to enable detection of the contact under appropriate illumination (due to the bending of the cantilever). After contacting, the nanometer scale XYZ stage can move the cantilever in the XYZ direction to deposit ink on the 2D surface and the 3D surface structure. The 360 degree motor driven rotating stage allows the cantilever to be always pulled rather than pushed (ie, in a direction parallel to its length, from its free end to its mating end; see example below). This prevents cantilever buckling and other problems that result in poor patterning results.

To apply ink to the cantilever, the cantilever is moved up by the coarse motor driven Z stage until it is above the level of the ink bottle rotation stage. The ink bottle rotation stage then rotates the ink bottle to the position just below the cantilever. The cantilever is then lowered into the ink bottle and the ink is coated on the cantilever. The cantilever then moves back up, and the ink bottle rotates out of the cantilever area. The cantilever is then ready to deposit ink on the substrate.

After the ink deposition in the given area is completed, the curing laser is driven. Through the mirror and beam splitter (or other device that selectively reflects light from the laser toward the substrate), the laser light is directed onto the area where the ink is deposited. Hardening can be observed when hardening occurs with the camera and microscope assembly through the beam splitter. The entire assembly can be moved remotely so that the assembly can be placed on the area of the substrate that needs repair. The required flat panel display support frame and remote placement system are not shown but are known in the art. Alternatively, the laser light can be directed down or at an angle using a gantry that can move the entire assembly over a distance (meters) to place the cantilever or curing laser on the repair area without a mirror. Note that the use of direct laser light can preclude microscopic observation of the curing process.

In another embodiment (FIG. 32), the task of detecting the exact height at which the microbrush or cantilever contacts the substrate is accomplished by computer monitoring of the output of the Z axis laser reflection sensor focused on the cantilever. On contact, a large change in sensor output occurs with sensitivity that allows detection of contact. After contacting, the nanometer scale XYZ stage can move the cantilever in the XYZ direction to deposit ink on the 2D surface and the 3D surface structure. In another embodiment (FIG. 33), the task of detecting the exact height at which the cantilever is in contact with the substrate is computer monitoring of the output of a confocal distance sensor (available from Keyence Corp.) targeting the cantilever. Is achieved by. The confocal sensor can include a built-in CCD array, which can be observed when laser curing occurs.

The present invention also provides a method for repairing the addition of a gap in an open trace on a flat panel display substrate by local deposition of precursor ink followed by curing of the ink to conductor form.

Providing a cantilever (or microbrush);

Providing a precursor ink;

Depositing the ink on the cantilever;

Providing a substrate surface;

Contacting the cantilever and the substrate surface such that ink is transferred from the cantilever to the substrate surface;

Curing the deposited ink.

Example  14: bidirectional entry  And Cantilever  rotation

In Figure 34, gold traces were deposited from a 5 micron tipless cantilever loaded with gold nanoparticle ink across the insulating gap between conductive ITO (indium tin oxide) electrodes. When this experiment is repeated several times, these gold traces are often discontinuous and appear to have a small gap close to only one of the ITO steps. 35 illustrates how a gap can be formed near the topography step when drawing a line using a tipless cantilever. In this figure, the cantilever draws a line with ink from right to left on top of two ITO islands on an insulating glass substrate separated by grooves (see Fig. 34). The cantilever end faithfully deposits ink on the right edge, but can rise from the bottom of the groove when the cantilever body strikes the left edge. This may form insulating lines after curing of the ink. A simple solution to this problem consists of (i) writing the first layer of ink from right to left, for example, and (ii) writing the second layer from left to right over the first layer (aka "bidirectional writing" method). ). Preferably, the cantilever is rotated 180 degrees before writing the second layer because the best patterning result (narrowest line) is obtained when moving the cantilever parallel to its path and from its free end towards its mating end. Otherwise, the cantilever can bend or bend to release the ink in unwanted areas. This is best achieved by including a cantilever rotation stage in the patterning instrument.

Those skilled in the art will recognize that there are various alternative embodiments and applications of the present invention. Such alternatives are considered to be within the scope of the present invention. In particular, this may include (i) fabrication of a network of conductive traces on a flat panel display; (ii) repair or manufacture of metal conductive traces and other flat panel display elements, including but not limited to a semiconductor (polysilicon) layer, a transparent conductive oxide layer (eg ITO); (iii) repair of color filters, particularly in flat panel displays; (iv) repair or manufacture of other types of flat panel or flexible displays; (v) repair of organic light emitting diode (OLED) displays; (vi) the manufacture or repair of masks used in the manufacture of semiconductor chips, including photomasks used in UV photolithography; (vii) manufacturing or repairing thin film resistors or other thick or thin film passive components; And (viii) the use of the cantilever for other micron scale precision deposition applications. The cantilever used for CMD can be improved for better ink retention or deposition capability. For example, the entire cantilever can be coated with a layer of polymer such as PDMS (polydimethylsiloxane). The patterning can be better controlled using an integrated actuator such as a cantilever with an integrated heater and a heat driven bimorph. A cantilever suitable for CMD, for example an AFM cantilever with an integrated chip for high resolution imaging or a cantilever with a heated chip for ink curing after deposition, can be coupled to the same chip along with other devices.

The following is an exemplary specification for open line repair.

Features Specifications Tolerance comment Line width 5 and 10 micron +/- 20% Line width? Height 0.1 micron +/- 30% Height is related to resistance (see below). Resistivity ~ 10 (μΩ? Cm) What is the maximum resistivity (μΩ? Cm) for line or repair? Line length Line length = 200 microns +/- 10 microns from specified length What is the longest line to fill in a single pass? Fill / cure time per repair 100 micron line deposition + 1 cure. 60 seconds or less What is the maximum allowable repair time? This helps to determine the writing speed and curing time. Curing conditions 200 ° C (depending on the ink used) Can I use a 170 ° C hot plate or choose a laser system for curing? adhesion Scotch tape test The ink withstands Scotch tape testing and water rinsing.

Claims (50)

Is a method of delivering ink to the substrate surface, Providing a tipless cantilever having a cantilever end; Providing ink disposed at the cantilever end; Providing a substrate surface; Moving the cantilever end or moving the substrate surface to transfer the ink from the cantilever end to the substrate surface. delete delete The method of claim 1, wherein the substrate is a substrate of a flat panel display. The method of claim 1, wherein the ink comprises one or more metals, metal salts, or metal nanoparticles. The method of claim 1, wherein the ink comprises one or more solvents having a boiling point above 100 ° C. 3. The method of claim 1, wherein the ink forms on the substrate surface a substrate surface that forms a structure having dimensions controlled by the geometry of the cantilever. delete The method of claim 1, wherein the ink forms a structure on the substrate surface and the structure delivers ink to the substrate surface that is exposed to melting, sintering or coalescing conditions. The method of claim 1, wherein the ink forms a structure on the substrate surface and the structure delivers ink to the substrate surface to be annealed. The method of claim 1, wherein the ink forms a structure on the substrate surface and the structure delivers ink to the substrate surface that is exposed to light. The method of claim 1, wherein the ink forms a structure on the substrate surface and the structure delivers ink to a substrate surface that is laser cured. The method of claim 1, wherein the ink forms a structure that is continuous after contact on the substrate surface. The method of claim 1, wherein the ink forms a structure on the substrate surface that is converted into a metal state having a resistivity of 1 μΩ · cm to 10 μΩ · cm. delete The method of claim 1, wherein the method is repeated to form layers of ink on the substrate surface. The method of claim 1, wherein the cantilever includes ink storage slits or channels. delete delete delete The method of claim 1, wherein the method delivers ink to a substrate surface for use in thin film transistor repair. The method of claim 1, wherein the cantilever is one of a plurality of cantilevers that deposit ink in parallel. The method of claim 1, wherein the ink is a polyol ink. The method of claim 1, wherein the ink comprises a metal salt with one or more alcohols or polyols. delete delete delete Is a method of writing a conductive metal, Providing two or more cantilevers, each having a cantilever end, wherein the cantilever can include a tip at the end or can be a tipless cantilever, the cantilevers having a gap of between 1 micron and 20 microns between the cantilevers; Providing more than one cantilever; Providing ink disposed within the gap; Providing a substrate surface; Contacting the at least two cantilevers with ink disposed in the gap with the substrate surface to transfer the ink from the gap to the substrate surface. 29. The method of claim 28, wherein the gap is between 1 micron and 5 microns. 29. The method of claim 28, wherein the gap is between 5 microns and 10 microns. 29. The method of claim 28, wherein the gap is between 10 microns and 20 microns. Ink formulations for nanolithography or microlithography, At least one metal salt and at least one solvent, Ink formulations have a concentration of 1 mg / 100 μL to 500 mg / 100 μL. 33. The ink formulation of claim 32, wherein the concentration of the metal salt is between 1 mg / 100 μL and 200 mg / 100 μL. 33. The ink formulation of claim 32, wherein the concentration of the metal salt is between 5 mg / 100 μL and 30 mg / 100 μL. 33. The ink formulation of claim 32, wherein the formulation further comprises two or more oligomeric or polymeric additives having different average molecular weights. 33. The ink formulation of claim 32, wherein the formulation further comprises one or more oligomers and one or more polymers. 33. The ink formulation of claim 32, wherein the formulation comprises two or more metal salts. 33. The ink formulation of claim 32, wherein said formulation further comprises an epoxy. A method for direct writing of a conductive metal or metal precursor, Providing a tipless cantilever having a cantilever end; Providing ink disposed at the cantilever end; Providing a substrate surface; Contacting the cantilever end with the substrate surface to transfer the ink from the cantilever end to the substrate surface; And the ink comprises one or more metals, one or more metal nanoparticles, or one or more metal salts. 40. The method of claim 39, wherein the cantilever is pulled instead of pushed. 40. The method of claim 39, wherein the tipless cantilever is part of an array of cantilevers. 40. The method of claim 39, wherein the ink comprises metal nanoparticles. 40. The method of claim 39, wherein the ink is cured after being delivered to the substrate surface. The method of claim 39, wherein the ink is cured at a temperature of 50 ° C. to 300 ° C. after it is delivered to the substrate surface. To deposit metal traces, Depositing a metal trace from a tipless cantilever loaded with nanoparticle ink across an insulating gap between conductive materials. A method for additive repair of a gap in an open trace on a flat panel display substrate by local deposition of precursor ink followed by curing of the ink in conductor form, Providing a cantilever; Providing a precursor ink; Depositing the precursor ink on the cantilever; Providing a substrate surface; Contacting the cantilever with the substrate surface to transfer the precursor ink from the cantilever to the substrate surface; Curing the deposited precursor ink in the form of a conductor. For repairing flat panel displays and other substantially flat circuits, (1) a micrometer wide cantilever for depositing ink on a substrate; (2) an XYZ stage on a micro / nanometer scale that provides fine movement of the cantilever; (3) a laser for curing the ink deposited on the substrate; (4) an ink supply mechanism or device for supplying the ink to the cantilever before the deposition; (5) a large moving Z stage mover for providing coarse Z moving for ink supply; (6) a mechanism comprising a rotating stage capable of positioning the cantilever at any angle with respect to a Z axis. 48. The instrument of claim 47 wherein the instrument further comprises an apparatus for detecting cantilever bending upon deposition of the ink. A mechanism for repairing gaps in open traces on flat panel display substrates and similar devices, (1) a cantilever adapted to receive ink; (2) a cantilever holding and placing device for contacting and translating said cantilever on a surface of said flat panel display substrate for patterning ink on said substrate in the shape of a repair patch; (3) an ink supply device for supplying the ink to the cantilever; (4) Optionally, an apparatus comprising a curing system for converting the deposited material into a low resistivity form for electrical conduction. 50. The system of claim 49, wherein the curing system is present, the curing system comprises a laser and its focusing optics, The cantilever arrangement device, (1) a nanometer resolution stage for controlling the movement of the cantilever along the X, Y, and Z axes; (2) a coarse long-range Z stage suitable for contacting the cantilever to the substrate; (3) a rotating stage capable of positioning the cantilever at any angle with respect to a Z axis; (4) Optionally, a mechanism including a cantilever contact detection device.

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