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EP-4739812-A1 - ATOMIC LAYER DEPOSITION METHODS FOR MAKING OMNIDIRECTIONAL STRUCTURAL COLOR MULTILAYER STRUCTURES

EP4739812A1EP 4739812 A1EP4739812 A1EP 4739812A1EP-4739812-A1

Abstract

A method of forming a multilayer structure that reflects an omnidirectional structural color by atomic layer deposition (ALD) includes introducing at least one reflective core particle into a reaction chamber and depositing a conformal dielectric layer encapsulating the at least one reflective core particle in a dielectric-layer ALD cycle. Subsequently, a conformal barrier layer encapsulating the conformal dielectric layer is deposited in a barrier-layer ALD cycle, and a conformal absorber layer encapsulating the conformal barrier layer is deposited in an absorber-layer ALD cycle.

Inventors

  • WU, SONGTAO
  • BANERJEE, DEBASISH
  • ZHANG, MINJUAN

Assignees

  • Toyota Jidosha Kabushiki Kaisha

Dates

Publication Date
20260513
Application Date
20240708

Claims (20)

  1. 1. A method of forming a multilayer structure that reflects an omnidirectional structural color by atomic layer deposition (ALD), comprising: introducing at least one reflective core particle into a reaction chamber; depositing a conformal dielectric layer encapsulating the at least one reflective core particle in a dielectric-layer ALD cycle; depositing a conformal barrier layer encapsulating the conformal dielectric layer in a barrier-layer ALD cycle; and depositing a conformal absorber layer encapsulating the conformal barrier layer in an absorber-layer ALD cycle.
  2. 2. The method of claim 1, wherein the at least one reflective core particle comprises a conformal protective layer encapsulating the at least one reflective core particle.
  3. 3. The method of claim 2, wherein the conformal protective layer is formed by ALD, CVD, or wet chemistry methods.
  4. 4. The method of claim 1, further comprising depositing a conformal outer protective layer encapsulating the conformal absorber layer in an outer-protective-layer ALD cycle.
  5. 5. The method of claim 1, further comprising depositing a second conformal barrier layer encapsulating the conformal absorber layer in a second barrier-layer ALD cycle; and depositing a second conformal dielectric layer encapsulating the second conformal barrier layer in a second dielectric-layer ALD cycle.
  6. 6. The method of claim 5, further comprising depositing a conformal outer protective layer encapsulating the second conformal dielectric layer in an outer-protective-layer ALD cycle.
  7. 7. The method of claim 1, wherein the dielectric-layer ALD cycle comprises, in sequence: supplying a first component selected from the group consisting of halides, alkyl, alkoxides, alkylamides, and carbonyls of Ti, Zn, Zr, Hf, Fe, Al, Pb, Ga, In, Si, Mg, K, and combinations thereof into the reaction chamber; purging the reaction chamber with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof; supplying a second component selected from the group consisting of O2, O3, H2O, H2O2, AS2O3, AS2O5, H2S, S2, Bn, HF, NH4F, SF 6 , and combinations thereof into the reaction chamber; and purging the reaction chamber with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof.
  8. 8. The method of claim 1, wherein the barrier-layer ALD cycle comprises, in sequence: supplying a first component is selected from the group consisting of halides, alkyl, alkoxides, alkylamides, and carbonyls of Al, Si, Mg, K, Zn, and combinations thereof into the reaction chamber; purging the reaction chamber purged with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof; supplying a second component selected from the group consisting of O2, O3, H2O, H2O2, Bn, HF, NH4F, and combinations thereof into the reaction chamber; and purging the reaction chamber is purged with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof.
  9. 9. The method of claim 1, wherein the absorber-layer ALD cycle comprises, in sequence: supplying a first component selected from the group consisting of halides, alkyl, alkoxides, alkylamides, and carbonyls of W, Cr, Ge, Ni, Pd, Ti, Si, V, Co, Mo, Nb, and combinations thereof into the reaction chamber; purging the reaction chamber with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof; supplying a second component selected from the group consisting of SiH4, Si2He, BH3, B2H6, H2, N2, NH3, O2, O3, H2O, H2O2, and combinations thereof into the reaction chamber; and purging the reaction chamber with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof.
  10. 10. The method of claim 4, wherein the outer-protective-layer ALD cycle comprises, in sequence: supplying a first component selected from the group consisting of halides, alkyl, alkoxides, alkylamides, and carbonyls of Al, Si, Mg, K, Zn, and combinations thereof into the reaction chamber; purging the reaction chamber with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof; supplying a second component selected from the group consisting of O2, O3, H2O, H2O2, Bn, HF, NH4F, and combinations thereof into the reaction chamber; purging the reaction chamber with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof; supplying trimethyl aluminum and water into the reaction chamber; and purging the reaction chamber with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof.
  11. 11. The method of claim 5, wherein the second barrier-layer ALD cycle comprises, in sequence supplying a first component selected from the group consisting of halides, alkyl, alkoxides, alkylamides, and carbonyls of Al, Si, Mg, K, Zn, and combinations thereof into the reaction chamber; purging the reaction chamber with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof; supplying a second component selected from the group consisting of O2, O3, H2O, H2O2, Bn, HF, NH4F, and combinations thereof into the reaction chamber; and purging the reaction chamber with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof.
  12. 12. The method of claim 5, wherein the second dielectric-layer ALD cycle comprises, in sequence: supplying a first component selected from the group consisting of halides, alkyl, alkoxides, alkylamides, and carbonyls of Ti, Zn, Zr, Hf, Fe, Al, Pb, Ga, In, Si, Mg, K, and combinations thereof into the reaction chamber; purging the reaction chamber with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof; supplying a second component selected from the group consisting of O2, O3, H2O, H2O2, AS2O3, AS2O5, H2S, S2, Bn, HF, NH4F, SF 6 , and combinations thereof into the reaction chamber; and purging the reaction chamber with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof.
  13. 13. The method of claim 1, wherein the reaction chamber, in each of the dielectric-layer ALD cycle, the barrier-layer ALD cycle, and the absorber-layer ALD cycle individually, comprises: a pressure that is greater than or equal to 13 pascals and less than or equal to 2666 pascals; and a temperature that is greater than or equal to 60°C and less than or equal to 150°C.
  14. 14. The method of claim 5, wherein the reaction chamber, in each of the second barrier-layer ALD cycle and the second dielectric-layer ALD cycle individually, comprises: a pressure that is greater than or equal to 13 pascals and less than or equal to 2666 pascals; and a temperature that is greater than or equal to 60°C and less than or equal to 150°C.
  15. 15. The method of claim 1 , wherein the at least one reflective core particle is selected from the group consisting of Au, Cu, Al, brass, bronze, TiN, Cr, stainless steel, alumina (AI2O3), silica (SiO2), bismuth oxychloride, glass materials, mica, and combinations thereof.
  16. 16. The method of claim 1 , wherein the conformal dielectric layer is selected from the group consisting of TiO2, ZnS, Z1O2, HfCh, FesCM, AlAs, Fe2O3, PbS, GaAs, InAs, SiO2, MgF2, KBr, ZnO, AI2O3, and combinations thereof; the conformal barrier layer is selected from the group consisting of AI2O3, SiO2, MgF2, KBr, ZnO, and combinations thereof; and the conformal absorber layer is selected from the group consisting of W, Cr, Ge, Ni, stainless steel, Pd, Ti, Si, V, TiN, Co, Mo, Nb, ferric oxide, and combinations thereof.
  17. 17. The method of claim 4, wherein the conformal outer protective layer is selected from the group consisting of SiO2, AI2O3, organosilane, organic phosphine, phosphates, and combinations thereof.
  18. 18. The method of claim 5, wherein the second conformal barrier layer is selected from the group consisting of A1 2 O 3 , SiO 2 , MgF2, KBr, ZnO, and combinations thereof; and the second conformal dielectric layer is selected from the group consisting of TiO2, ZnS, ZrO 2 , HfO 2 , Fe 3 O 4 , AlAs, Fe 2 O 3 , PbS, GaAs, InAs, SiO 2 , MgF 2 , KBr, ZnO, A1 2 O 3 , and combinations thereof.
  19. 19. The method of claim 6, wherein the conformal outer protective layer is selected from the group consisting of SiO 2 , A1 2 O 3 , organosilane, organic phosphine, phosphates, and combinations thereof.
  20. 20. The method of claim 1, wherein the conformal dielectric layer has a thickness that is greater than or equal to 5 nm and less than or equal to 500 nm; the conformal barrier layer has a thickness that is less than or equal to 50 nm; and the conformal absorber layer has a thickness that is greater than or equal to 2 nm and less than or equal to 50 nm.

Description

ATOMIC LAYER DEPOSITION METHODS FOR MAKING OMNIDIRECTIONAL STRUCTURAL COLOR MULTILAYER STRUCTURES FIELD OF THE INVENTION [0001] The present disclosure is related to methods for making multilayer structures that reflect an omnidirectional structural color (OSC), and in particular to methods for making multilayer structures comprising metal and metal oxide layers encapsulating at least one reflective core particle, where at least one of the metal and metal-oxide layers are deposited by atomic layer deposition (ALD), and a barrier layer is positioned between each adjacent metal and metal-oxide layer. BACKGROUND OF THE INVENTION [0002] Preparing OSC multilayer structures can be a complex, expensive process because, in part, very tight control over layer thicknesses and layer quality is required. Small variation in the layer thickness and minute contamination in layer materials (i.e., including the infiltration of materials between adjacent layers) can affect the optical performance of OSC multilayer structures. [0003] However, conventional deposition methods used to form multilayer structures can vary in complexity and cost depending on the desired thickness of the layer and the material that makes up a given layer. Also, conventional deposition methods limit the size and shape of substrates or the direction of deposition leaving the sides and edges of substrates uncoated or unevenly coated. The defects on the sides and at the edges of the substrates can lead to, for example, unwanted scattering or transmission loss. [0004] Forming OSC multilayer structures using ALD methods are known. However, conventional ALD methods are low-volume and therefore are cost-prohibitive to manufacture at a commercial scale. SUMMARY OF THE INVENTION [0005] A first aspect comprises a method of forming a multilayer structure that reflects an omnidirectional structural color by atomic layer deposition (ALD), the method comprising: introducing at least one reflective core particle into a reaction chamber; depositing a conformal dielectric layer encapsulating the at least one reflective core particle in a dielectric-layer ALD cycle; depositing a conformal barrier layer encapsulating the conformal dielectric layer in a barrier- layer ALD cycle; and depositing a conformal absorber layer encapsulating the conformal barrier layer in an absorber-layer ALD cycle. [0006] A second aspect includes the method of the first aspect, wherein the at least one reflective core particle comprises a conformal protective layer encapsulating the at least one reflective core particle. [0007] A third aspect includes the method of the second aspect, wherein the conformal protective layer is formed by ALD, CVD, or wet chemistry methods. [0008] A fourth aspect includes the method of any of the previous aspects , further comprising depositing a conformal outer protective layer encapsulating the conformal absorber layer in an outer-protective-layer ALD cycle. [0009] A fifth aspect includes the method of any of the previous aspects, further comprising depositing a second conformal barrier layer encapsulating the conformal absorber layer in a second barrier-layer ALD cycle; and depositing a second conformal dielectric layer encapsulating the second conformal barrier layer in a second dielectric-layer ALD cycle. [0010] A sixth aspect includes the method of the fifth aspect, further comprising depositing a conformal outer protective layer encapsulating the second conformal dielectric layer in an outer- protective-layer ALD cycle. [0011] A seventh aspect includes the method of any of the previous aspects, wherein the dielectric-layer ALD cycle comprises, in sequence: supplying a first component selected from the group consisting of halides, alkyl, alkoxides, alkylamides, and carbonyls of Ti, Zn, Zr, Hf, Fe, Al, Pb, Ga, In, Si, Mg, K, and combinations thereof into the reaction chamber; purging the reaction chamber with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof; supplying a second component selected from the group consisting of O2, O3, H2O, H2O2, AS2O3, AS2O5, H2S, S2, Bn, HF, NH4F, SF6, and combinations thereof into the reaction chamber; and purging the reaction chamber with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof. [0012] An eighth aspect includes the method of any of the previous aspects, wherein the barrier-layer ALD cycle comprises, in sequence: supplying a first component is selected from the group consisting of halides, alkyl, alkoxides, alkylamides, and carbonyls of Al, Si, Mg, K, Zn, and combinations thereof into the reaction chamber; purging the reaction chamber purged with a purge gas selected from the group consisting of nitrogen, argon, and combinations thereof; supplying a second component selected from the group consisting of O2, O3, H2O, H2O2, Bn, HF, NH4F, and combinations thereof into the reaction chamber; and purging the reaction chamber is purged