TW201543978A - Pulsed-mode direct-write laser metallization - Google Patents

Abstract

A method for manufacturing includes coating a substrate (22) with a matrix (28) containing a material to be patterned on the substrate. A pattern is fixed in the matrix by directing a pulsed energy beam to impinge on a locus of the pattern so as to cause adhesion of the material to the substrate along the pattern without fully sintering the material in the pattern. The matrix remaining on the substrate outside the fixed pattern is removed, and after removing the matrix, the material in the pattern is sintered.

Description

Direct writing laser metallization in pulse mode

The present invention relates generally to the production of printed wiring on circuit substrates, and in particular to methods and systems for direct writing of metal features.

Direct laser sintering of metallic inks is one of the known techniques for metallization of printed wiring. For example, U.S. Patent Application Publication No. 2008/0286488 describes a method of forming a conductive film based on depositing a non-conductive film on one surface of a substrate. The film contains a plurality of copper nanoparticles, and at least a portion of the film is exposed to light by photo sintering or melting the copper nanoparticles such that the exposed portions are electrically conductive.

Kumpulainen et al. describe a direct laser sintering technique in "Low Temperature Nanoparticle Sintering with Continuous Wave and Pulse Lasers" ( Optics & Laser Technology 43 (2011), pp. 570-576). The authors refer to "printed electronics" in which nano inks printed on the surface of a substrate contain additives such as dispersants and carrier liquids, which are provided by varying the viscosity and separating the nanoparticles of the ink. Good printing properties. In the sintering process, the ink particles are heated to a specific temperature of the ink and the carrier liquid and dispersant are evaporated from the ink. The additional heating after evaporation causes the nanoparticles to begin to cohere. Laser sintering is said to achieve short sintering times and selective sintering, making it possible to have printed structures containing fragile active components produced by other techniques. The paper describes tests performed with two different types of lasers: pulsed waves and continuous waves.

Further, after the priority date of this patent application, Theodorakos et al. further describe the laser in "Selective Laser Sintering of Ag Nanoparticles Ink for Applications in Flexible Electronics" ( Applied Surface Science 336 (2015), pp. 157-162). Sintering technology. The authors investigated the possibility of operating three different laser sources at 532 nm and 1064 nm as an efficient tool for selective laser sintering of Ag nanoparticle ink layers on flexible substrates: continuous wave (CW) or Pulse nanosecond laser and pulse picosecond laser. Theoretical simulations indicate that the picosecond laser pulse limits the heat affected zone to only a few microns around the irradiated zone of the ink layer. These forecasts have been confirmed experimentally.

Embodiments of the present invention provide enhanced methods and systems for laser based direct writing of traces on a substrate.

Thus, in accordance with an embodiment of the present invention, a method for manufacturing is provided, the method comprising: coating a substrate with a substrate, the substrate containing a material to be patterned on the substrate, and by directing a pulse The energy beam is incident on a track of a pattern to cause the material to adhere to the substrate along the pattern to secure a pattern in the substrate without completely sintering the material in the pattern. The substrate remaining on the substrate outside the fixed pattern is removed, and the material in the pattern is sintered after the substrate is removed.

In certain embodiments, the material to be patterned comprises nanoparticle. In one disclosed embodiment, the material in the form of the nanoparticles is electrically conductive, and the pulsed energy beam comprises a radiation pulse having a selected one of a flux and a repetition rate such that after the pattern is fixed One of the traces maintains a resistivity that is at least ten times greater than that achieved by completely sintering the material in the pattern after removal of the substrate.

Typically, directing the pulsed energy beam includes directing a pulse train of the energy beam onto each of the tracks on the substrate.

In these disclosed embodiments, the pulsed energy beam has a pulse repetition rate of at least 1 MHz and possibly at least 10 MHz.

Typically, in addition to the material to be patterned, the substrate also includes an organic compound, and directing the pulsed energy beam includes directing a pulse train of the energy beam having a selected one of the pulse fluxes for incomplete sintering. The material in the pattern causes the organic compound to evaporate from the substrate. The per-pulse flux applied in fixing the pattern is selected such that the material remains sufficiently porous to permit permeation of the organic compound in the absence of ablation or delamination of the material due to the evaporation of the organic compound. The pores in the material evaporate.

In some embodiments, sintering the material comprises applying a bulk sintering process to the pattern secured to the substrate. Alternatively, sintering the material includes: directing a pulse of the pulsed energy beam to sinter the pattern secured to the substrate.

In one disclosed embodiment, coating the substrate comprises drying the substrate on the substrate prior to irradiating the coated substrate. Additionally or alternatively, removing the substrate comprises applying a solvent to remove the substrate remaining on the substrate outside of the fixed pattern.

According to an embodiment of the present invention, a method for manufacturing is also provided, the method comprising: coating a substrate with a substrate, the substrate containing a material to be patterned on the substrate, and guiding comprising a slope One pulse of the pulse of the time-varying curve is irradiated with a flux on a point on the coated substrate sufficient to fix the material to the substrate and to sinter the material at that point.

In the disclosed embodiments, in addition to the material to be fixed to the substrate, the substrate also contains an organic compound, and the ramp time-varying curve and the flux are selected so as not to cause The ablation or delamination of the material by the evaporation of the compound causes the organic compound to evaporate from the substrate prior to sintering the material. In certain embodiments, the material comprises nanoparticles and the material is sintered to cause the nanoparticles Melt at this point.

In one disclosed embodiment, the pulses have a duration of no more than 20 ns.

In some embodiments, directing the pulsed energy beam comprises forming a pattern of the material on the substrate by directing the pulses to illuminate a sequence of dots defining the pattern on the coated substrate. The points in the sequence may not overlap each other. Typically, the method includes removing the substrate remaining on the substrate outside of one of the traces of the pattern after forming the pattern.

In accordance with an embodiment of the present invention, there is additionally provided a system for manufacturing, the system comprising a coating machine configured to coat a substrate with a substrate, the substrate containing a pattern to be patterned on the substrate One of the materials. A writing machine configured to illuminate a track of a pattern by directing a pulse of energy light to cause the material to adhere to the substrate along the pattern without completely sintering the material in the pattern A pattern is fixed in the matrix. A substrate removal machine is configured to remove the substrate remaining on the substrate outside of the fixed pattern. A sintering machine is configured to sinter the material in the pattern after the substrate is removed.

According to an embodiment of the present invention, there is further provided a system for manufacturing, the system comprising: a coating machine configured to coat a substrate with a substrate, the substrate containing a pattern to be patterned on the substrate One of the materials. A write machine configured to direct a pulsed energy beam comprising a pulse having a ramped time-varying curve to illuminate a point on the coated substrate with a flux sufficient to secure the material to the The substrate and the material is sintered at this point.

The invention will be more fully understood from the following detailed description of embodiments of the invention

20‧‧‧ system

22‧‧‧Substrate

24‧‧‧Coating machine

26‧‧‧Drying machine

28‧‧‧Material

30‧‧‧Laser writing machine/machine/write machine

32‧‧‧pulse laser/laser

34‧‧‧

36‧‧‧beam scanner

38‧‧‧ Controller

40‧‧‧ memory

42‧‧‧ Traces

44‧‧‧Matrix removal machine/machine

46‧‧‧Sintering machine

48‧‧‧High intensity light source/source

50‧‧‧Sintered Trace/Nano Particles

52‧‧‧ Traces

60‧‧‧lower curve/curve

62‧‧‧Upper curve/curve

70‧‧‧Rectangular pulse volume curve/quantity curve

72‧‧‧Slope-type quantitative curve/quantity curve

74‧‧‧ light spots

76‧‧‧ Damaged area

78‧‧‧ light spots

80‧‧‧ pattern

82‧‧‧ points

1 shows one of direct writes based on lasers in accordance with an embodiment of the present invention. A schematic pictorial illustration of a stage in the operation of the system and the system; FIGS. 2A-2E illustrate a sequential phase of a program forming one of the patterns in accordance with an embodiment of the present invention Schematic top view of a substrate of a pattern; FIGS. 3A and 3B are schematic cross-sectional views of a substrate on which a trace is written, as illustrated by successive stages of a process for forming a trace, in accordance with an embodiment of the present invention. Figure 4A to Figure 4D are schematic cross-sectional views of a substrate on which a trace is written at a continuous time during the fixation of the trace, in accordance with an embodiment of the present invention; Figure 4E is in accordance with the present invention A schematic cross-sectional view of the substrate and trace of FIGS. 4A through 4D after annealing of the trace in one embodiment; FIG. 5 illustrates a write to a substrate in accordance with an embodiment of the present invention. A graph of the dependence of one of the upper traces and one of the pulse energy thresholds of the damage to the trace; FIG. 6A is a pulsed parameter having variations thereon according to an embodiment of the invention a pulse beam with a little matrix A schematic top view of a substrate on which a spot is written; and FIG. 6B is a schematic top view of a pattern formed on a substrate by applying a pulsed beam to a sequence of dots in accordance with an embodiment of the present invention. .

Overview

As explained in the above-referenced PCT patent application PCT/IL2014/000014, single-step direct laser sintering of metallic inks and other nanoparticle sinterable inks generally does not give sufficiently uniform results. (The term "nanoparticles" as used in this specification and the scope of the claims is intended to mean microscopic particles having at least one dimension of less than 100 nm.) This problem stems at least in part from the heat transfer that occurs during the local sintering process. The uneven thermal diffusion under these conditions results in a thermal change which in turn leads to inconsistent sintering. This effect is most pronounced when dealing with high resolution patterning of small metal features of the order of a few microns. At the same time, direct sintering of metallic inks requires high laser flux (approximately tens to hundreds of J/cm ² ) which makes the process slow and inefficient when processing large area patterns.

In some embodiments of the invention, the writing step is separated from the sintering step in a manner that enhances the uniformity and reliability of the resulting trace. A substrate is coated with a suitable substrate and the substrate can be dried after coating to remove excess solvent. (These substrates typically include an ink, paste or suspension containing one of the nanoparticles, and are simply referred to herein as "NP inks" for convenience.) Then, in the case where the nanoparticles are not completely sintered A next pulse energy beam source, such as a laser, is scanned over the substrate to write the desired pattern. The term "in the case of incomplete sintering" as used in the specification and claims means that the nanoparticles in the bulk of the matrix remain substantially separated from one another such that in the case of metallic nanoparticles, this stage The resistivity at the trace is still at least ten times greater than the final resistivity that will be achieved after complete sintering.

This stage of the process in which the energy beam is written into the pattern is referred to herein as "fixing" the pattern into the substrate. In some embodiments, the beam of light has a pulse sequence (or "cluster") having a flux sufficient to cause the material to adhere to the substrate along the pattern but substantially below the threshold for complete sintering. Scan over the trace of the pattern to be written on the substrate. This fixation step stabilizes the matrix against subsequent removal (relative to the unirradiated substrate). The use of pulsed irradiation in this step enhances the quality of the traces of the pattern by reducing the likelihood of damage due to rapid expansion of the gas trapped in the matrix.

During this stationary phase, the material remains sufficiently porous to permit evaporation of the organic compound in the matrix through the pores in the material prior to complete sintering of the nanomaterial, thereby preventing erosion of the material which may otherwise be caused by excessive rapid evaporation of the organic compound or Delamination. To ensure such controlled evaporation, a laser (or other source of energy) typically directs the pulse train to each of the locations at a high repetition rate (for example, at least 1 MHz and possibly greater than 10 MHz). Each pulse flux is selected such that the desired porosity of the substrate is maintained until the fixation is completed.

After the pattern has been fixed in this manner, the substrate is removed from all non-fixed regions such that only the stabilized pattern remains. For example, this removal can be accomplished by application of a chemical solvent or by radiation ablation. Typically, the substrate is then uniformly heated in a bulk sintering process to sinter the nanoparticles in the remaining pattern. This method achieves uniform metallization as compared to the unevenness typically encountered when using direct laser sintering. This is also particularly useful for printing thick lines because the laser fixation step is less sensitive to thickness than full laser sintering, while for example, in an oven, overall sintering works well for coarse ink traces.

Thus, these embodiments provide a simple and fast metallization procedure with fewer steps than conventional methods. The first step of the procedure involves only relatively low laser power. Subsequently, an actual metallization requiring a high throughput can be implemented using a high power source with a large area coverage, such as a heat source or a high power flash or a high power laser or laser array. Step (integral sintering procedure). Because these embodiments avoid high local temperatures associated with single-step direct laser sintering, they are suitable for use in the patterning of precision flexible substrates such as plastics and foils.

In other embodiments, a pulsed laser or other energy beam is used for sintering and fixation. In this case, the inventors have found that pulses having a ramped time-varying curve achieve substantially better results than conventional pulses, such as square wave pulses, whose intensity over time is substantially uniform. A ramp-type time-varying curve is advantageous because it causes the organic compound to evaporate from the substrate coated on the substrate before sintering and thus melting of the nanomaterial. The time-volume curve and the flux of the pulses are selected to enhance this effect and thus avoid erosion or delamination of the patterned material due to evaporation of the organic compound. These single-step embodiments are particularly, but not exclusively, suitable for forming a pattern of individual sintered spots or such spots of light on a substrate.

The use of one of the pulsed lasers for direct writing (for fixed or direct sintering) in embodiments of the present invention achieves high resolution with the possibility of adaptive calibration, as in digital imaging techniques. Metal lines and other features formed by the disclosed techniques can be achieved The width is as small as micrometers. The resolution is limited only by the size of the laser spot that can be generally focused to a range of 1 μm to 2 μm or less. The quality of resolution and line definition can be improved by tuning the parameters of the laser during scanning. Any pattern can be drawn in this way, which may be derived directly from computer-aided design and computer-aided manufacturing (CAD/CAM) data.

In some embodiments, the entire cycle of writing and sintering is performed without contacting the substrate. This feature is particularly beneficial for applications such as photovoltaic cell and plastic electronic foil production.

Other potential applications of the techniques described herein include, for example, liquid crystal displays and organic light emitting diode (OLED) displays, rear end metallization, touch screen metallization, OLED lighting device routing, and plastics. Printed electronic circuits and devices on foil. The techniques described herein can be similarly applied to various dielectric, ceramic, semiconductor, polymer, paper, and metal substrates with various NP materials (including not only metals but also semiconductors and dielectric particles (such as ceramic particles). )) Write the pattern.

Although the embodiments disclosed herein specifically refer to the formation of a single metallization layer for simplicity, in alternative embodiments, traces may be written into multiple layers by appropriate repetition of the techniques of the present invention. The same or different inks are used in each of the layers.

System specification

Referring now to Figures 1 and 2A through 2E, the figures schematically illustrate a system 20 based on laser direct writing and a program in accordance with an embodiment of the present invention. 1 is a pictorial illustration of component devices and stages in one of the processes implemented by system 20. 2A-2E are schematic top views of a substrate 22 on which a trace pattern is written in system 20, illustrated in successive stages of the process. As mentioned earlier, substrate 22 can comprise, for example, glass or other dielectric, ceramic, semiconductor, plastic foil or other polymeric material, paper or metal.

First, a coating machine 24 is coated with a uniform thick layer of substrate 28 (Fig. 2B), such as a metal nanoparticle (NP) ink, a metal NP paste, or a metal complex ink or paste. Substrate 22 (Fig. 2A). The ink or paste may contain, for example, silver, copper, nickel, palladium and/or gold nanoparticles and alloys of such metals, or possibly non-metallic nanoparticles (such as tantalum or nano ceramic particles) ). The layer thickness of the substrate 28 can vary from about 0.2 [mu]m to more than 10 [mu]m depending on the desired end result. Coating machine 24 can be applied to any suitable zone coating technique known in the art (such as screen printing, slot die coating or strip coating, spray coating, gravure coating or spin coating).

Optionally, a drying machine 26 dries the substrate that has been applied to the substrate 22. The ink or paste applied by the coating machine 24 typically contains a significant amount of solvent, and the metal volume content at this stage does not exceed about 40%. Therefore, it may be advantageous (although not mandatory) to dry the substrate prior to the laser scanning step to enhance the stability of the substrate and reduce the loss of laser energy to the solvent. Possible drying methods include low temperature baking (by convection or by radiation), air flow, vacuum drying or a combination of such techniques.

A laser writing machine 30 secures one of the traces 42 to the substrate 28 as illustrated in Figure 2C. In a typical embodiment, the substrate 22 having the substrate 28 coated thereon is mounted on a suitable stage 34, and a beam scanner 36 scans a pulsed laser 32 (or other suitable pulse energy source) over the substrate. beam.

The laser 32 "writes" the desired pattern into the substrate by exposing the substrate to a sharply defined sequence of laser pulses at a predetermined location on the film. The pattern is typically determined by a controller 38 based on the appropriate CAD/CAM data stored in a memory 40. Pulse parameters including wavelength, spot size, flux, duration, pulse shape, scan speed, and repetition rate are selected to optimize the quality of the pattern, as further described below. For high throughput, multiple laser beams can be scanned simultaneously over different regions of the substrate (generated by multiple lasers or by splitting a single high power pulsed laser beam into sub-beams, as illustrated in Figure 1). Note), where each beam is independently controlled.

Various types of laser and laser systems can be used for the laser writing machine 30. In some embodiments, a source of laser diodes is directly modulated at a high rate for from one nanosecond to several tens of nanometers. A pulse of the desired shape is emitted on one of the time scales. In some such embodiments, the pulse shape is ramped (as further described below) having a ramp time tuned to match the trace thickness. The pulse parameters can also be tuned according to the width of the trace, where shorter pulses are used when very thin lines are required. The choice of pulse parameters also depends on whether the machine 30 is only used for the fixation that will be subsequently sintered overall or whether the laser 32 is used to fully sinter the trace.

Alternatively, a CW laser source (such as a CW fiber laser) can be modulated at a desired high repetition rate to provide the desired pulsed beam. A fast external modulator (such as an electro-optic modulator or acousto-optic modulator) can be used for this purpose.

3A shows a schematic cross-sectional view of one of the traces 42 secured to the substrate 28 by the writing machine 30, in accordance with an embodiment of the present invention. Trace 42 at this stage typically does not contain a significant amount of sintered metal, but is more adherent and more stable against substrate 22 removal due to laser exposure (as a result of a photon effect or thermal effect) than the surrounding substrate 28. a material state. As mentioned above, the laser parameters of the writing machine 30 are selected to provide the localized changes required for the properties of the substrate. The optimum parameters will vary depending on the precise matrix material and size and the method of writing selected and will be determined in each case by empirical testing and evaluation. In either case, the power applied at this stage is much less than the power required to completely sinter the nanoparticles in the matrix.

After irradiation, a substrate removal machine 44 removes the unsecured substrate 28 from all areas of the substrate 22 leaving only traces 42 (Fig. 2D). Machine 44 can include, for example, a solvent bath in which the substrate is submerged to wash away one of the matrices other than the pattern. Alternatively, or as such, machine 44 may employ other types of removal techniques (such as chemical ablation or physical ablation of unfixed substrates).

FIG. 3B is a schematic cross-sectional view of trace 42 remaining on substrate 22 following removal of substrate 28 by machine 44.

Finally, the traces 42 remaining on the substrate 22 after substrate removal are sintered in a sintering machine 46 to produce sintered traces 50 as shown in Figure 2E. If the substrate 22 (for example In the case where it is usually a glass substrate, which is suitable for this treatment, the sintering machine 46 may comprise a conventional sintering oven. Alternatively, the sintering machine 46 can be sintered using photons that are generally preferably suitable for sensitive substrates such as plastic foils. Alternatively, other sintering methods can be adapted to sensitive substrates, such as plasma sintering or microwave sintering, both of which can sinter a metallic ink pattern without damaging the underlying plastic substrate.

In general, photon sintering (or microwave sintering or plasma sintering) is preferred for oven sintering when treating copper inks in a surrounding atmosphere (due to the tendency of copper to readily oxidize) and treating inks containing other metals that are susceptible to oxidation. Oven sintering using copper ink can also be used in a suitable atmosphere (i.e., a non-oxidizing atmosphere and/or a reducing atmosphere).

The sintering machine 46 as shown in FIG. 1 is sintered using photons having a high intensity light source 48 scanned over the surface of the substrate 22. Source 48 may include, for example, a set of laser diode strips configured as a column or a stack, thus providing the desired flux even over a large area. Commercially available laser diode strips are used in the nearby infrared range (approximately 800 nm to 1000 nm) (such as by Oclaro Inc. (San Jose, Calif.), Coherent Inc. (Santa Clara, CA) or Jenoptik (Germany) Jena City) produces them to achieve an average power of approximately several kilowatts.

The next section of this specification will describe a method by which the writing machine 30 can be applied to secure the desired pattern to the substrate 28. In an alternate embodiment illustrated in Figures 6A and 6B, the writing machine 30 can also perform sintering by applying sufficient energy to a target point of a defined pattern on the substrate. In this latter case, a separate sintering machine 46 may not be required. The techniques set forth herein can be applied in conjunction with the materials and methods set forth in the above-referenced PCT patent application PCT/IL2014/000014, and other suitable materials and methods well known in the art.

Pulsed laser pattern fixed

Referring now to Figures 4A-4E, which are schematic cross-sectional views of a substrate 22 at a continuous stage of writing a trace 52 onto a substrate in accordance with one embodiment of the present invention. Figure 4A 4D shows the substrate 28 at successive times during the fixation of the trace, while FIG. 4E shows the trace 52 after annealing.

In particular, Figures 4A-4D show the cumulative effect of one of the pulse bursts directed to one of the substrates 28 by the laser 32. At the beginning of the procedure, the nanoparticles 50 are suspended in one of the bulk volatile organic components of the matrix 28. Each successive laser pulse heats the substrate and evaporates an additional amount of organic components such that the density of the nanoparticles 50 in the matrix 28 increases from one pulse to the next. However, due to thermal diffusion within the substrate and substrate, the increase in density above the volume of the substrate is substantially uniform. Thus, as shown in Figure 4D, the pores through which the evaporative material can escape remain between the nanoparticles 50 in the matrix 28 even after almost all of the organic material has been expelled from the substrate. As shown in Figure 4E, the nanoparticles are melted together together to form traces 52 only during the subsequent sintering step.

In contrast, the inventors have discovered that when a CW laser is used for pattern fixation, the nanodensity tends to increase particularly in the upper layer of the substrate, leaving the organic material trapped in the lower portion. Such heating of the trapped organic material can result in rapid boiling evaporation, resulting in erosion or delamination of the surrounding nanomaterial, thereby degrading the quality of the traces formed on the substrate.

In contrast, when pulsed radiation is used for immobilization, the pulse parameters are selected to promote gradual evaporation of the organic components of the matrix 28 during the course of a pulse burst while avoiding solidification of the upper layer of the nanoparticle 50. The inventors have found that having short pulses of pulse width in the range of from about 1 ns to tens of nanoseconds produces the best results. A high repetition rate (at least 1 MHz and possibly 10 MHz or higher) is desirable in order to achieve a fast fix of the trace and thus a high program throughput. Pulse flux and other parameters are typically selected to maximize throughput without potentially damaging the trace.

Figure 5 is a diagram illustrating a window for fixing a trace by a laser pulse in accordance with an embodiment of the present invention. The data points in the graph indicate the number of pulses applied to a given point on the substrate 22 on the abscissa and the per-pulse flux on the ordinate. A lower curve 60 indicates that the pattern is fixed in the substrate for any given number of pulses. The minimum flux required. In other words, as long as the pulse at a given point has at least this minimum flux for a specified number of pulses, the substrate will not be washed away from that point after the stationary phase. An upper curve 62 indicates the maximum flux that can be used without damaging the trace for a given number of pulses. Beyond this flux level, rapid heating of the substrate tends to result in erosion and/or delamination.

Thus, curve 60 and curve 62 define a pulsed fixed working window of substrate 28. As can be seen in Figure 5, a larger number of low flux pulses produces a wider window and thus a larger range of program tolerances. Within these limits, the pulse flux and number of pulses applied to each location can be selected to produce a fixed desired solidity when the program throughput is maximized. The optimum choice will also depend on other process parameters (such as the thickness and composition of the substrate 28 as well as the laser wavelength and spot size). Curves 60 and 62 were generated on a 460 nm thick substrate film using a diode laser operating at 980 nm. Alternatively, a pulsed laser in the form of other portions of the ultraviolet, visible or infrared range can be used. The number of pulses required to fix the pattern (as reflected by curve 60) tends to scale exponentially with film thickness.

Pulsed laser sintering

6A is a schematic top plan view of a substrate on which one of the spots 74, 78 has been written in a point array by a pulsed beam having one of varying pulse parameters, in accordance with an embodiment of the present invention. In this embodiment, the substrate is coated with a substrate containing one of the nanoparticle materials. A pulsed laser beam is directed at a point on the substrate that is sufficient to secure the material to the substrate and sufficient to sinter the material at each point in the array. The laser beam in this case is also a diode laser operating at 980 nm in pulse mode. The peak power of the laser pulses applied in the formation of spots 74 and 78 increases from the bottom of the array shown in Figure 6A to the top thereof, while the pulse duration increases from left to right, with the maximum pulse duration set. It is about 20ns. Similar results are obtained at other wavelengths.

Two different pulse amount curves are used to sinter the spot shown in Figure 6A: a rectangular pulse rate curve 70 is used to sinter the spot 74, and a ramp pulse rate curve 72 is used to sinter the spot 78. The instantaneous power at the pulse increases with the pulse duration (the largest of which The quantity curve 72 is "slope type" in the sense that power occurs near the trailing edge of the pulse. The ramp time variation curve and the ramp pulse flux are selected to cause the organic compound to evaporate from the substrate prior to sintering the nanoparticle material without causing erosion or delamination of the material due to boiling evaporation of the organic compound. This advantageous effect of the ramp-type quantitative curve can be seen from a wide range of peak power and pulse duration, as illustrated by spot 78. In contrast, the spot 74 formed using the quantitative curve 70 exhibits a damaged region 76 due to ablation and delamination of the nanoparticle material.

The ramped gauge curve 72 is particularly useful for forming a single sintered spot on a substrate. These spots will typically have a larger diameter than the laser beam itself due to the lateral thermal diffusion of the beam energy above the vicinity of the substrate. (The ramp beam volume curve is usually less critical in online scanning because each point in the line is preheated at the previous point of sintering except for the initial point.) A single spot of this type can be used The laser pulse is directed to illuminate a sequence of dots defining the pattern on the coated substrate to form a pattern on the substrate. The points in the sequence may not overlap each other, that is, the area of the beam used to form the laser pulse adjacent to the spot does not need to overlap itself, since each spot has a specific ratio for fixing and sintering the spot. The laser beam is one area larger. After the pattern is formed in this manner, the remaining substrate on the substrate other than the track of the pattern is removed, as in the previous embodiment.

Figure 6B is a schematic top plan view of a pattern 80 formed on a substrate by applying a pulsed beam to a sequence of dots 82, in accordance with an embodiment of the present invention. In this example, pattern 80 includes a line formed by the overlap of spots 78, but points 82 themselves do not overlap. A pattern substantially in any desired form can be formed efficiently in this manner.

It will be appreciated that the various embodiments set forth above are cited by way of example, and the invention is not limited to what has been particularly shown and described herein. Rather, the scope of the invention includes both combinations and sub-combinations of the various features described hereinabove, as well as the various features which are apparent to those skilled in the <RTIgt; Changes and modifications.

20‧‧‧ system

22‧‧‧Substrate

24‧‧‧Coating machine

26‧‧‧Drying machine

28‧‧‧Material

30‧‧‧Laser writing machine/machine/write machine

32‧‧‧pulse laser/laser

34‧‧‧

36‧‧‧beam scanner

38‧‧‧ Controller

40‧‧‧ memory

42‧‧‧ Traces

44‧‧‧Matrix removal machine/machine

46‧‧‧Sintering machine

48‧‧‧High intensity light source/source

50‧‧‧Sintered Trace/Nano Particles

Claims (38)

A method for manufacturing, comprising: coating a substrate with a substrate containing a material to be patterned on the substrate; by directing a pulse of energy beam onto a track of a pattern to Incompletely sintering the material in the pattern such that the material is adhered to the substrate along the pattern to fix the pattern in the substrate; the substrate remaining on the substrate outside the fixed pattern is moved Dividing; and sintering the material in the pattern after removing the substrate. The method of claim 1, wherein the material to be patterned comprises nanoparticle. The method of claim 2, wherein the material in the form of the nanoparticles is electrically conductive, and wherein the pulsed energy beam comprises a radiation pulse having a selected one of a flux and a repetition rate such that after the pattern is fixed One of the traces maintains a resistivity that is at least ten times greater than that achieved by completely sintering the material in the pattern after removal of the substrate. The method of claim 1, wherein directing the pulsed energy beam comprises directing a pulse train of the energy beam to illuminate each of the trajectories on the substrate. The method of claim 1, wherein the pulsed energy beam has a pulse repetition rate of at least 1 MHz. The method of claim 5, wherein the pulse repetition rate is at least 10 MHz. The method of claim 1, wherein the substrate comprises an organic compound in addition to the material to be patterned, and wherein directing the pulsed energy beam comprises directing the energy beam having a selected one of the pulse fluxes. A pulse sequence is such that the organic compound evaporates from the substrate without completely sintering the material in the pattern. The method of claim 7, wherein the per-pulse flux applied in fixing the pattern is selected such that the material remains sufficiently porous to be ablated or delaminated in the absence of the evaporation of the organic compound. In this case, the organic compound is allowed to permeate through the pores in the material. The method of any one of claims 1 to 8, wherein sintering the material comprises applying a bulk sintering procedure to the pattern that is fixed to the substrate. The method of any one of claims 1 to 8, wherein sintering the material comprises: further directing a pulse of the pulsed energy beam to sinter the pattern secured to the substrate. The method of any one of claims 1 to 8, wherein coating the substrate comprises drying the substrate on the substrate prior to irradiating the coated substrate. The method of any one of claims 1 to 8, wherein removing the substrate comprises applying a solvent to remove the substrate remaining on the substrate outside the fixed pattern. A method for manufacturing, comprising: coating a substrate with a substrate, the substrate containing a material to be patterned on the substrate; and guiding a pulse energy beam including a pulse having a ramp time-varying curve The flux is applied to a point on the coated substrate with a flux sufficient to secure the material to the substrate and to sinter the material at the point. The method of claim 13, wherein the substrate comprises an organic compound in addition to the material to be fixed to the substrate, and wherein the ramp time amount curve and the flux are selected so as not to cause an organic compound The erosion or delamination of the material caused by the evaporation causes the organic compound to evaporate from the substrate prior to sintering the material. The method of claim 13, wherein the material comprises nanoparticles, and wherein sintering the material causes the nanoparticles to melt at the point. The method of claim 13, wherein the pulses have a duration of no more than 20 ns between. The method of any one of claims 13 to 16, wherein directing the pulsed energy beam comprises: forming on the substrate by directing the pulses to illuminate a sequence of dots defining the pattern on the coated substrate One of the patterns of the material. The method of claim 17, wherein the points in the sequence do not overlap each other. The method of claim 17, and comprising removing the substrate remaining on the substrate outside the track of one of the patterns after forming the pattern. A system for manufacturing comprising: a coating machine configured to coat a substrate with a substrate comprising a material to be patterned on the substrate; a writing machine having Configuring to illuminate a pattern along one of the traces of a pattern by directing a pulse of energy light to cause the material to adhere to the substrate along the pattern to thereby secure a pattern to the substrate without completely sintering the material in the pattern In the matrix; a substrate removal machine configured to remove a substrate remaining on the substrate outside the fixed pattern; and a sintering machine configured to sinter the substrate after removing the substrate The material in the pattern. The system of claim 20, wherein the material to be patterned comprises nanoparticle. The system of claim 21, wherein the material in the form of the nanoparticles is electrically conductive, and wherein the pulsed energy beam comprises a radiation pulse having a selected one of a flux and a repetition rate such that after the pattern is fixed One of the traces maintains a resistivity that is at least ten times greater than that achieved by completely sintering the material in the pattern after removal of the substrate. The system of claim 20, wherein the writing machine is configured to direct a pulse train of the energy beam to each of the tracks on the substrate. The system of claim 20, wherein the pulsed energy beam has a pulse repetition rate of at least 1 MHz. The system of claim 24, wherein the pulse repetition rate is at least 10 MHz. A system of claim 20, wherein the substrate comprises an organic compound in addition to the material to be patterned, and wherein the writing machine is configured to direct the energy beam having a selected one per pulse flux A pulse sequence is such that the organic compound evaporates from the substrate without completely sintering the material in the pattern. The system of claim 26, wherein the per-pulse flux applied in fixing the pattern is selected such that the material remains sufficiently porous to be ablated or delaminated in the absence of the evaporation of the organic compound. In this case, the organic compound is allowed to evaporate through the pores in the material. The system of any one of claims 20 to 27, wherein the sintering machine is configured to apply a bulk sintering procedure to the pattern that is secured to the substrate. The system of any one of claims 20 to 27, wherein the sintering machine is configured to further apply a pulse of the pulsed energy beam to sinter the pattern secured to the substrate. The system of any one of clauses 20 to 27, and comprising a drying machine configured to dry the substrate on the substrate prior to irradiating the coated substrate. The system of any one of clauses 20 to 27, wherein the substrate removal machine is configured to apply a solvent to remove the substrate remaining on the substrate outside the fixed pattern. A system for manufacturing, comprising: a coating machine configured to coat a substrate with a substrate containing a material to be patterned on the substrate; and a writing machine Configurable to guide including having a ramp time amount One pulse of the pulse of the line of energy illuminates a point on the coated substrate with a flux sufficient to secure the material to the substrate and to sinter the material at that point. The system of claim 32, wherein the substrate comprises an organic compound in addition to the material to be fixed to the substrate, and wherein the ramp time-varying curve and the flux are selected so as not to cause The ablation or delamination of the material caused by the evaporation of the organic compound causes the organic compound to evaporate from the substrate prior to sintering the material. The system of claim 32, wherein the material comprises nanoparticles, and wherein sintering the material causes the nanoparticles to melt at the point. The system of claim 32, wherein the pulses have a duration of no more than 20 ns. The system of any one of clauses 32 to 35, wherein the writing machine is configured to form on the substrate by directing the pulses to illuminate a sequence of dots defining the pattern on the coated substrate One of the patterns of the material. The system of claim 36, wherein the points in the sequence do not overlap each other. The system of claim 36, and comprising a substrate removal machine configured to remove the substrate remaining on the substrate outside of one of the traces of the pattern.