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EP-4735935-A2 - SURFACE ACTIVATED CHEMICAL VAPOR DEPOSITION AND USES THEREOF

EP4735935A2EP 4735935 A2EP4735935 A2EP 4735935A2EP-4735935-A2

Abstract

Surface activated chemical vapor deposition (SACVD) methods and uses thereof are described herein. Polymeric coatings deposited by SACVD demonstrate high uniformity and conformality, as compared to other deposition techniques, such as initiated chemical vapor deposition (iCVD). Such polymeric coatings are useful for various applications, such as semiconductor applications.

Inventors

  • CHEN, BENNY
  • O'SHAUGHNESSY, W. SHANNAN
  • YOU, Siheng Sean

Assignees

  • Gvd Corporation

Dates

Publication Date
20260506
Application Date
20240701

Claims (20)

  1. We claim: 1. A method for forming a polymeric coating on at least one substrate or material, the method comprising the steps of: (i) placing the at least one substrate or material into a reaction chamber; (ii) sealing and purging the reaction chamber under a vacuum; (iii) wherein the reaction chamber is at an initiation temperature sufficient to activate one or more gaseous initiators; wherein one or more surfaces of the at least one substrate or material have a surface temperature equal to or substantially equal to the initiation temperature; and (iv) flowing one or more gaseous monomers, the one or more gaseous initiators, and optionally one or more carrier gases into the reaction chamber to form the polymeric coating on at least a portion of a surface of the at least one substrate or material; wherein the partial pressure of the one or more gaseous monomers is sufficient to form the polymeric coating on the portion of the surface at the surface temperature; optionally wherein the surface temperature during step (iv) is sufficient to preclude the one or more gaseous monomers or the one or more gaseous initiators from exceeding their saturation pressure at the surface temperature; wherein the polymeric coating comprises carbon, hydrogen, and oxygen; and wherein the polymeric coating has an atomic carbon content of at least about 30% of the total atomic composition of the polymeric coating.
  2. 2. A method for forming a polymeric coating on at least one substrate or material, the method comprising the steps of: (i) placing the at least one substrate or material onto a platform within a reaction chamber; wherein the platform and the reaction chamber and/or components thereof are independently temperature controlled; (ii) sealing and purging the reaction chamber under a vacuum; 45662721.1 (iii) wherein the platform is at an initiation temperature sufficient to activate one or more gaseous initiators; wherein one or more surfaces of the at least one substrate or material have a surface temperature equal to or substantially equal to the initiation temperature; and (iv) flowing one or more gaseous monomers, the one or more gaseous initiators, and optionally one or more carrier gases into the reaction chamber to form the polymeric coating on at least a portion of a surface of the at least one substrate or material; wherein the reaction chamber and/or components thereof are independently heated to a reaction chamber temperature, wherein the reaction chamber temperature is lower than the initiation temperature and the surface temperature during step (iv); optionally wherein the components comprise walls of the reaction chamber; wherein the partial pressure of the one or more gaseous monomers is sufficient to form the polymeric coating on the portion of the surface at the surface temperature; optionally wherein the reaction chamber temperature during step (iv) is sufficient to preclude the one or more gaseous monomers or the one or more gaseous initiators from exceeding their saturation pressure at the reaction chamber temperature; wherein the polymeric coating comprises carbon, hydrogen, and oxygen; and wherein the polymeric coating has an atomic carbon content of at least about 30% of the total atomic composition of the polymeric coating.
  3. 3. The method of any one of claims 1-2, wherein the polymeric coating forms via vinyl polymerization, wherein the one or more gaseous monomers comprise monomers having at least one vinyl moiety thereon.
  4. 4. The method of claim 3, wherein the vinyl polymerization is a free-radical vinyl polymerization.
  5. 5. The method of any one of claims 1-4, wherein the polymeric coating has a microscale conformality to the surface of at least about 50%, as determined by microtrench method. 45662721.1
  6. 6. The method of claim 5, wherein the microscale conformality is at least about 60%, 65%, 70%, 75%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, or 99.9%, as determined by the microtrench method.
  7. 7. The method of any one of claims 1-6, wherein the initiation temperature ranges from about 0 ºC to about 400 ºC, 0 °C to 300 °C, 0 °C to 200 °C, 0 °C to 100 °C, 20 °C to 400 °C, 20 °C to 300 °C, 20 °C to 200 °C, 20 °C to 100 °C, 50 °C to 400 °C, about 50 ºC to about 300 ºC, about 50 ºC to about 200 ºC, or about 50 ºC to about 100 ºC.
  8. 8. The method of any one of claims 1-7, wherein the initiation temperature ranges from about 50 ºC to about 100 ºC.
  9. 9. The method of any one of claims 1-8, wherein the one or more gaseous monomers comprise carbon-containing monomers each independently having an atomic carbon content of at least about 25%, 30%, 35%, 40%, 45%, or 50% of the total atomic composition of the carbon-containing monomer; or in a range from about 25% to 50% of the total atomic composition of the carbon-containing monomer.
  10. 10. The method of any one of claims 1-9, wherein the one or more gaseous initiators comprise carbon-containing initiators each independently having an atomic carbon content of at least about 20%, 25%, 30%, 35%, 40%, 45%, 50%, or 55% of the total atomic composition of the carbon-containing initiator; or in a range from about 20% to 55% of the total atomic composition of the carbon-containing initiator.
  11. 11. The method of any one of claims 1-10, wherein the polymeric coating has an atomic carbon content is in the range of about 30 to 70%, 30 to 65%, 30 to 60%, 30 to 55%, 30 to 50%, 30 to 45%, 30 to 40%, or 30 to 35% of the total atomic composition of the polymeric coating. 45662721.1
  12. 12. The method of any one of claims 1-10, wherein the polymeric coating has an atomic carbon content above about 30%, above about 40%, or above about 50% of the total atomic composition of the polymeric coating.
  13. 13. The method of any one of claims 1-10, wherein the polymeric coating has an atomic carbon content of about 50% of the total atomic composition of the polymeric coating.
  14. 14. The method of any one of claims 1-13, wherein the method further comprises a step of reducing organic content in the polymeric coating following step (iv), such as by applying an annealing step.
  15. 15. The method of claim 14, wherein the annealing step occurs during the flowing step (iv).
  16. 16. The method of claim 14, wherein the annealing step occurs after the flowing step (iv).
  17. 17. The method of claim 16, further comprising prior to the annealing step, transferring the substrate or material having the polymeric coating thereon into another chamber where the annealing step is carried out.
  18. 18. The method of any one of claims 14-17, wherein the annealing step occurs at a temperature ranging from about 50 °C to 800 °C, 50 °C to 750 °C, 50 °C to 700 °C, 50 °C to 650 °C, 50 °C to 600 °C, 50 °C to 550 °C, 50 °C to 500 °C, 50 °C to 450 °C, 50 °C to 400 °C, 50 °C to 350 °C, 50 °C to 300 °C, 50 °C to 250 °C, 50 °C to 200 °C, 50 °C to 150 °C, or 50 °C to 100 °C.
  19. 19. The method of any one of claims 14-18, wherein the annealing step is carried out under a process gas selected from the group consisting of nitrogen, argon, ammonia, hydrogen, syn gas, and combinations thereof; and wherein the process gas is free or substantially free of oxygen (O 2 ) gas; or wherein the process gas comprises oxygen (O 2 ) gas or air. 45662721.1
  20. 20. The method of any one of claims 14-19, wherein the annealing step occurs for a time period ranging from about 2 minutes to about 3 hours.

Description

SURFACE ACTIVATED CHEMICAL VAPOR DEPOSITION AND USES THEREOF CROSS-REFERENCE TO RELATE APPLICATIONS This application claims the benefit of and priority to U.S. Provisional Application No. 63/567,076, filed March 19, 2024, and to U.S. Provisional Application No.63/510,920, filed June 29, 2023, which are hereby incorporated by reference in their respective entirety. FIELD OF THE INVENTION This invention is in the field is surface activated chemical vapor deposition which can be used, for example, to form carbon coatings and films. BACKGROUND OF THE INVENTION Coatings play a critical role throughout many industries where they are applied to surfaces for a variety of reasons such as sealing to protect a surface from the environment, adding mechanical protection, imparting optical effects, modifying surface properties, and enhancing biological or chemical compatibility. A significant benefit of modifying a surface with a coating is that a relatively small quantity of material can be used to dictate surface properties over a large area without altering the properties of the bulk material. Typical processes for applying coatings include spraying, dipping, painting, and immersion in chemical baths. These application methods utilize liquids which add complications related to curing, surface tension, and viscous effects that can lead to pinholes, limit conformality, and increase the minimum practical thickness of the coating. In many industries, the importance of coating conformality has become increasingly important as substrates become more intricate and surface area to volume ratios increase. Chemical vapor deposition (CVD) is a subset of coating application processes which apply coatings directly from the vapor phase. The desired coating material is directly synthesized from gaseous precursors. However, typical CVD processes rely on a spatially-located energy source to activate the chemical synthesis process, such as filaments, plasma, ultraviolet irradiation, or lasers. These energy sources can cause conformality issues imposed by line- of-sight limitations, directionally influenced electric fields, and high energy molecules that readily react upon impact which can also cause damage to the resultant coating. These factors ultimately limit the conformality of the resultant coating. 45662721.1 Thus, there exists a need for alternate deposition methods which permit facile deposition of coatings without unduly limiting the conformality of coatings produced. Further, there is a need for improved methods for coating semiconductors, for example, microelectronics stacks, boards, electronic device components, and 3-D integrated heterogeneous packages, having high aspect ratio features, which can benefit from coatings exhibiting high conformality which provide various benefits. Therefore, it is an object of the invention to provide deposition methods which produce coatings with high conformality. Therefore, it is also an object of the invention to provide deposition methods where the conformal coatings produced can provide particular compositions and properties on coated substrates and materials. Therefore, it is a further object of the invention to use such methods to produce substrates or materials having highly conformal coatings for various applications. SUMMARY OF THE INVENTION Methods for surface activated chemical vapor deposition to form highly conformal carbon coatings and films, and uses thereof, are described herein. In some instances, a surface activated chemical vapor deposition (SACVD) may be carried out under isothermal or non-isothermal conditions. The SACVD methods described can be used to form or deposit polymeric coatings or films of particular compositions. In one non-limiting instance, a first example of an isothermal SACVD method for forming a polymeric coating on at least one substrate or material can include the steps of: (i) placing the at least one substrate or material into a reaction chamber; (ii) sealing and purging the reaction chamber under a vacuum; (iii) wherein the reaction chamber is at an initiation temperature sufficient to activate one or more gaseous initiators; wherein one or more surfaces of the at least one substrate or material have a surface temperature which is equal to or substantially equal to the initiation temperature; and 45662721.1 (iv) flowing one or more gaseous monomers, the one or more gaseous initiators, and optionally one or more carrier gases into the reaction chamber to form the polymeric coating on at least a portion of a surface of the at least one substrate or material; wherein the partial pressure of the one or more gaseous monomers is sufficient to form the polymeric coating on the portion of the surface at the surface temperature; wherein the polymeric coating comprises carbon, hydrogen, and oxygen; and wherein the polymeric coating has an atomic carbon content of at least about 30% of the total atomic composition of the polymeric coating. In some inst