Two-step, direct-write laser metallization
View Patent ↗A method for manufacturing includes coating a substrate ( 22 ) with a matrix ( 28 ) containing a material to be patterned on the substrate. A pattern ( 42 ) is fixed in the matrix by directing an energy beam to impinge on the coated substrate so as to fix the pattern in the matrix without fully sintering 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.
1. A method for manufacturing, comprising:
coating a substrate with a matrix containing a material to be patterned on the substrate and comprising a photosensitive surfactant additive, which migrates to a top surface of the matrix so as to form an outer layer;
irradiating the coated substrate with an energy beam so as to activate the surfactant additive in order to fix a pattern in the outer layer of the matrix without fixing a bulk of the matrix or sintering the material that is to be patterned in the matrix, such that a resistivity of the patterned material remains at least ten times greater than a final resistivity that is to be achieved after full sintering;
removing the matrix remaining on the substrate outside the fixed pattern; and
after removing the matrix, sintering the material in the pattern so as to achieve the final resistivity of the patterned material.
2. The method according to claim 1 , wherein irradiating the coated substrate causes polymerization or crosslinking of the outer layer of the matrix.
3. The method according to claim 2 , wherein the substrate photosensitive surfactant additive comprises a photoinitiator, and wherein irradiating the coated substrate causes the photoinitiator to release free radicals in the outer layer, which induce the polymerization or crosslinking.
4. The method according to claim 2 , wherein irradiating the coated substrate causes heating in the outer layer, which thermally induces the polymerization or crosslinking.
5. The method according to claim 1 , wherein the material to be patterned comprises nanoparticles.
6. The method according to claim 1 , wherein sintering the material comprises applying a bulk sintering process to the pattern fixed on the substrate.
7. The method according to claim 1 , wherein coating the substrate comprises drying the matrix on the substrate before irradiating the coated substrate.
8. The method according to claim 1 , wherein irradiating the coated substrate comprises directing the energy beam to impinge on a locus of the pattern.
9. The method according to claim 1 , wherein removing the matrix comprises applying a solvent to remove the matrix remaining on the substrate outside the fixed pattern.
10. The method according to claim 1 , wherein removing the matrix comprises ablating the matrix remaining on the substrate outside the fixed pattern.
11. A method for manufacturing, comprising:
coating a substrate with a matrix comprising a sacrificial resin and containing nanoparticles to be patterned on the substrate;
irradiating the coated substrate with an energy beam so as to fix a pattern in the matrix by modifying a state of the sacrificial resin so as to cause cohesion between the nanoparticles without fully sintering the nanoparticles, such that a resistivity of the pattern remains at least ten times greater than a final resistivity that is to be achieved after full sintering;
removing the matrix remaining on the substrate outside the fixed pattern; and
after removing the matrix, sintering the nanoparticles in the pattern so as to achieve the final resistivity of the pattern.
12. The method according to claim 11 , wherein irradiating the coated substrate releases thermal energy in the matrix, which causes at least one of polymerization and crosslinking of a molecular component within the pattern.
13. The method according to claim 11 , wherein the nanoparticles comprise a metal, and wherein irradiating the coated substrate causes formation of a coordination polymer linking the metal to a ligand.
14. The method according to claim 11 , wherein sintering the nanoparticles comprises applying a bulk sintering process to the pattern fixed on the substrate.
15. The method according to claim 11 , wherein coating the substrate comprises drying the matrix on the substrate before irradiating the coated substrate.
16. The method according to claim 11 , wherein irradiating the coated substrate comprises directing the energy beam to impinge on a locus of the pattern.
17. The method according to claim 11 , wherein irradiating the coated substrate comprises directing the energy beam to impinge on an area of the coated substrate area that excludes a locus of the pattern.
18. The method according to claim 11 , wherein removing the matrix comprises applying a solvent to remove the matrix remaining on the substrate outside the fixed pattern.
19. The method according to claim 11 , wherein removing the matrix comprises ablating the matrix remaining on the substrate outside the fixed pattern.
20. The method according to claim 11 , wherein modifying the state of the sacrificial resin comprises ablating or burning the resin within the pattern.
21. The method according to claim 11 , wherein modifying the state of the sacrificial resin comprises softening or melting the sacrificial resin, so that upon cooling, the sacrificial resin adheres to the nanoparticles.
22. A method for manufacturing, comprising:
coating a substrate with a matrix containing a material to be patterned on the substrate;
irradiating the coated substrate with a first energy beam so as to fix a pattern in the matrix while increasing a reflectivity of the matrix within a locus of the pattern by directing the energy beam to impinge on the locus of the pattern without fully sintering the material in the matrix;
ablating the matrix remaining on the substrate outside the fixed pattern without ablating the locus of the pattern by irradiating the matrix with a second energy beam at a fluence that is less than an ablation threshold of the matrix within the locus of the pattern; and
after ablating the matrix, sintering the material in the pattern.
23. The method according to claim 22 , wherein the material to be patterned comprises nanoparticles.
24. The method according to claim 22 , wherein sintering the material comprises applying a bulk sintering process to the pattern fixed on the substrate.
25. A system for manufacturing, comprising:
a coating machine, which is configured to coat a substrate with a matrix comprising a sacrificial resin and containing nanoparticles to be patterned on the substrate;
a writing machine, which is configured to irradiate the coated substrate with an energy beam so as to fix a pattern in the matrix by modifying a state of the sacrificial resin so as to cause cohesion between the nanoparticles without fully sintering the nanoparticles, such that a resistivity of the pattern remains at least ten times greater than a final resistivity that is to be achieved after full sintering;
a matrix removal machine, which is configured to remove the matrix remaining on the substrate outside the fixed pattern; and
a sintering machine, which is configured to sinter the material in the pattern after removal of the matrix so as to achieve the final resistivity of the pattern.