Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
  • H01L21/02104—Forming layers
  • H01L21/02107—Forming insulating materials on a substrate
  • H01L21/02225—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer
  • H01L21/0226—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a deposition process
  • H01L21/02282—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a deposition process liquid deposition, e.g. spin-coating, sol-gel techniques, spray coating
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
  • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
  • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
  • H01L21/28—Manufacture of electrodes on semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/268
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D1/00—Processes for applying liquids or other fluent materials
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D1/00—Processes for applying liquids or other fluent materials
  • B05D1/60—Deposition of organic layers from vapour phase
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
  • B05D3/04—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by exposure to gases
  • B05D3/0493—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by exposure to gases using vacuum
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
  • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
  • C23C16/4412—Details relating to the exhausts, e.g. pumps, filters, scrubbers, particle traps
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
  • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
  • C23C16/448—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for generating reactive gas streams, e.g. by evaporation or sublimation of precursor materials
  • C23C16/4486—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for generating reactive gas streams, e.g. by evaporation or sublimation of precursor materials by producing an aerosol and subsequent evaporation of the droplets or particles
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
  • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
  • C23C16/455—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for introducing gases into reaction chamber or for modifying gas flows in reaction chamber
  • C23C16/45563—Gas nozzles
  • C23C16/4558—Perforated rings
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
  • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
  • C23C16/46—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating characterised by the method used for heating the substrate
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
  • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
  • C23C16/48—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating by irradiation, e.g. photolysis, radiolysis, particle radiation
  • C23C16/482—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating by irradiation, e.g. photolysis, radiolysis, particle radiation using incoherent light, UV to IR, e.g. lamps
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
  • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
  • C23C16/52—Controlling or regulating the coating process
• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C26/00—Coating not provided for in groups C23C2/00 - C23C24/00
  • C23C26/02—Coating not provided for in groups C23C2/00 - C23C24/00 applying molten material to the substrate
• • C—CHEMISTRY; METALLURGY
  • C30—CRYSTAL GROWTH
  • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
  • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
  • C30B29/60—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape characterised by shape
  • C30B29/68—Crystals with laminate structure, e.g. "superlattices"
• • C—CHEMISTRY; METALLURGY
  • C30—CRYSTAL GROWTH
  • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
  • C30B7/00—Single-crystal growth from solutions using solvents which are liquid at normal temperature, e.g. aqueous solutions
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L28/00—Passive two-terminal components without a potential-jump or surface barrier for integrated circuits; Details thereof; Multistep manufacturing processes therefor
  • H01L28/40—Capacitors
  • H01L28/55—Capacitors with a dielectric comprising a perovskite structure material
  • H01L28/56—Capacitors with a dielectric comprising a perovskite structure material the dielectric comprising two or more layers, e.g. comprising buffer layers, seed layers, gradient layers
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10N30/00—Piezoelectric or electrostrictive devices
  • H10N30/01—Manufacture or treatment
  • H10N30/07—Forming of piezoelectric or electrostrictive parts or bodies on an electrical element or another base
  • H10N30/074—Forming of piezoelectric or electrostrictive parts or bodies on an electrical element or another base by depositing piezoelectric or electrostrictive layers, e.g. aerosol or screen printing
  • H10N30/076—Forming of piezoelectric or electrostrictive parts or bodies on an electrical element or another base by depositing piezoelectric or electrostrictive layers, e.g. aerosol or screen printing by vapour phase deposition
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
  • H01L21/02104—Forming layers
  • H01L21/02107—Forming insulating materials on a substrate
  • H01L21/02109—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates
  • H01L21/02112—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer
  • H01L21/02172—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer the material containing at least one metal element, e.g. metal oxides, metal nitrides, metal oxynitrides or metal carbides
  • H01L21/02197—Forming insulating materials on a substrate characterised by the type of layer, e.g. type of material, porous/non-porous, pre-cursors, mixtures or laminates characterised by the material of the layer the material containing at least one metal element, e.g. metal oxides, metal nitrides, metal oxynitrides or metal carbides the material having a perovskite structure, e.g. BaTiO3
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L28/00—Passive two-terminal components without a potential-jump or surface barrier for integrated circuits; Details thereof; Multistep manufacturing processes therefor
  • H01L28/40—Capacitors
  • H01L28/55—Capacitors with a dielectric comprising a perovskite structure material
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K3/00—Apparatus or processes for manufacturing printed circuits
  • H05K3/10—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern
  • H05K3/105—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern by conversion of non-conductive material on or in the support into conductive material, e.g. by using an energy beam

Definitions

• the invention relates to methods for depositing high quality films of complex (compound) materials on substrates at high deposition rates, and apparatus for effecting such methods.
• the invention relates to nonreactive chemical vapor deposition (CVD) methods and apparatus for depositing high quality, stoichiometrically-correct, thin films of a large variety of complex compounds at high deposition rates utilizing stabilized liquid compound sources.
• CVD nonreactive chemical vapor deposition
• the present invention has been developed to overcome the many problems and disadvantages associated with known deposition techniques for depositing thin films of complex chemical compounds including those discussed above, and to generally fulfill a great need in the art by providing a production worthy process which can be used for easily and economically producing thin films (from a few angstroms to microns in thickness) of various complex materials such as ferroelectrics, superconductors, and metal oxides.
• Fig. 1 is a schematic view of a CVD apparatus according to a first embodiment of the invention.
• Fig. 2 is an enlarged plan view of a nozzle assembly and an exhaust assembly used in the embodiment of Fig. 1.
• Fig.3 is an enlarged schematic view of a manifold system used in the first and second embodiments of the invention.
• Fig. 4 is a vertical cross sectional view of a preferred apparatus for forming a mist of a stabilized solution according to the present invention.
• Figs. 5a and 5b show modifications of the apparatus of Fig. 4.
• Fig. 6 is a schematic flow chart showing the preparation of a stabilized solution to be used in forming a thin film of lead zirconium titanate according to the present invention.
• stabilized sources or stabilized solutions of desired chemical compounds will initially be prepared and then mists or vapors of the solutions will be generated, flowed into a deposition chamber and deposited in thin films/layers on substrates disposed within the deposition chamber.
• Such stabilized solutions include at least all of those used in known liquid application techniques and specifically include sol-gels (which include alcohols as the solvent base thereof), metallorganic decomposition (MOD) formulations (which utilize n-decanoic acid as the solvent base thereof), solutions having water as the solvent base thereof, solutions having carboxylic acid as the solvent base thereof, etc.
• the term "stabilized source” as used herein is intended to designate a source which is obtained by mixing precursors for each element using sol-gel techniques, or other wet chemistry mixing techniques, which lead to a common solvent, and then using the solution having that common solvent as the sole source for the entire compound. Other sources may also be used in parallel for doping or modifying the compound. In the stabilized source the elements are already in the compound in solution with the common solvent or metallorganic precursor.
• the stabilized solutions used in the present invention are substantially less toxic and easier to handle than the corresponding reactants which are used in conventional, reactive CVD methods as discussed above, whereby the stabilized solutions can be handled and processed at substantially lower cost than the corresponding reactants.
• the stabilized compound sources assures high quality of the thin films produced thereby because the stabilized source can be accurately and consistently produced such that the desired chemical compound contained therein is uniformly, stoichiometricalh/ correct, and because the deposition methods of the present invention do not involve any chemical reactions which might destabilize the chemical compound of its predetermined molecular formulation. Instead, thin films of the stabilized source are directly deposited on substrates from a mist/vapor under vacuum at ambient temperatures and subsequently dried.
• Fig. 1 there is shown a thin film deposition apparatus according to a preferred embodiment of the invention, the apparatus being generally designated at 1.
• the apparatus 1 generally comprises a vacuum chamber 2, a substrate holder 4, a barrier plate 6, a nozzle assembly 8, and an exhaust assembly 10.
• the vacuum chamber 2 includes a main body 12, a lid 14 which is securable over the main body to define an enclosed space within the vacuum chamber, and the chamber is connected to an appropriate vacuum source (not shown) as generally indicated at 16.
• the lid 14 is preferably pivotally connected to the main body 12 using a hinge as indicated at 18.
• the substrate holder 4 is preferably supported on a rotatable shaft 20 which is in turn connected to a motor (not shown) so that the holder may, if desired, be rotated during a deposition process.
• Indicated at 22 is an insulating connector which electrically insulates the substrate holder 4 and a substrate 5 supported thereon from the rest of the deposition apparatus 1 so that a DC or AC (RF) bias can be created between the substrate holder 4 and the barrier plate 6, if desired, utilizing the DC/RF feedthrough indicated at 23.
• RF AC
• Such a DC bias could be utilized, for example, for field-poling of thin films as they are being deposited on the substrate 5.
• an electrical source (not shown) would be operativery connected across the barrier 6 and the substrate holder 4.
• the barrier plate 6 is preferably made of an electrically conductive material such as stainless steel, and is of sufficiently large size to extend completely over the substrate 5 in parallel thereto so that a vaporized source or mist as injected by the nozzle assembly 8 is forced to flow between the plate 6 and the substrate holder 4 over the substrate 5.
• the barrier plate 6 is preferably connected to the lid 14 by a shaft 24 so that the plate 6 will be moved away from the substrate 5 whenever the lid is opened.
• the shaft 24 is preferably adjustable in length so that the spacing between the holder 4 and the plate 6 can be adjusted depending on the source materials, the flow rate, etc. For example, the spacing may be adjustable to define a spacing in the range of 2 - 50 mm.
• the nozzle assembly 8 preferably includes an input tube 26 which receives a vaporized source from a manifold assembly 40 as discussed below in relation to Fig. 3, and an arcuate nozzle tube 28 having a plurality of small holes with removable screws 30 provided in a uniformly spaced manner along a surface of the tube 28 facing inwardly of the deposition chamber 2.
• the screws 30 can be selectively removed depending on the stabilized source, flow rate, etc. to adjust the flow of the vaporized source over the substrate 5.
• Indicated at 32 are end caps of the tube 28.
• the structure of the exhaust assembly 10 is substantially the same as that of the nozzle assembly 8, except that a pipe 34 leads to a vacuum/exhaust source (not shown).
• the arcuate tube 28 of the nozzle assembly 8 and the corresponding arcuate tube of the exhaust assembly 10 will preferably surround respective, oppositely disposed peripheral portions of the substrate 5, and the arcuate tubes will be spaced from each other across a central or intermediate portion of the substrate 5.
• the substrate holder 4, the barrier plate 6, the nozzle assembly 8 and the exhaust assembly 5 collectively cooperate to define a relatively small deposition cavity surrounding an upper/exposed surface of the substrate 5, and within which the vaporized source is substantially contained throughout the deposition process.
• the manifold assembly 40 is utilized for supplying a vaporized source to the nozzle assembly 8, and generally comprises a mixing chamber 42, a plurality of inlets 44 which are connected to corresponding source generators 46 through respective valves 48, a valve 50 for regulating flow from the mixing chamber 42 to the nozzle assembly 8, and an exhaust valve 52.
• one or more of the source generators 46 are utilized to generate one or more different vaporized sources or mists which are then flowed into the mixing chamber 42 through the valves -48 and inlets 44.
• the vaporized sources as flowed into the mixing chamber 42 are mixed to form a single, uniform vaporized source or mist, which is then flowed into the vacuum chamber 2 at an appropriate flow rate through the valve 50.
• the valve 50 can be selectively closed off so that the vacuum chamber 2 can be pumped down to dry a deposited film of a stabilized liquid source, or to clean and purge the system when necessary.
• the outlet of the exhaust valve 52 is connected to a vacuum source (not shown) so that, when necessary to exhaust purge one or more of the mist generators 46, the valve 50 can be closed off, the valve 52 and one or more of the valves -48 can be opened, and the mixing chamber 42 can be pumped down to clean and purge the source generators) and the mixing chamber.
• a mist will be flowed from the manifold assembly 40 into the nozzle assembly 8 at ambient temperature or slightly above room temperature.
• the generator 46 includes a closed container 54, an ultrasonic transducer 56 fluid-tightly sealed into the bottom of the container 54, a valve 58 for introducing a stabilized liquid source such as a sol-gel or an MOD formulation into the container 54 while the container is maintained under sealed, vacuum-tight conditions, and an inlet port 60 and an outlet port 62 for passing a carrier gas through the container 54.
• a stabilized liquid source such as a sol-gel or an MOD formulation
• a stabilized liquid source 64 will be introduced into the container 54 through the valve 58 up to an appropriate level as measured by a level-detecting means (not shown), the transducer 56 is activated to generate a mist 66 of the stabilized liquid source, and an appropriate carrier gas is passed through the mist 66 via the ports 60, 62 where it becomes wet or saturated with the mist, and the wet carrier gas is then passed from the outlet port 62 into the manifold assembly -40 as discussed above.
• the carrier gas will normally, be an inert gas such as argon or helium, but may comprise a reactive gas in appropriate situations.
• the valve 58 will be selectively actuated as necessary to maintain the stabilized liquid source 64 at an appropriate level within the container 54.
• the preferred source generator -46 as shown in Fig. 4 is particularly advantageous because it creates a vaporized source which can be effectively flowed or injected into the vacuum deposition chamber 2 without complications such as freezing.
• Fig. 5a there is shown a source generator -46' which is modification of the source generator 46 shown in Fig. 4 whereby the ultrasonic transducer 56 does not come into contact with the stabilized liquid source 64.
• the stabilized liquid source 64 is contained within a first, closed container 54' while the transducer 56 is sealingly fitted to a bottom wall of a second, open container 68, a working medium 70 such as water or another liquid is disposed in the second container 68 over the transducer, and the first container 54' is disposed in spaced relation above an upper surface of the working medium 70 such that a mist plume 72 of the working medium created by the ultrasonic transducer contacts a bottom wall of the first container 54' for thereby creating the mist 66 of the stabilized liquid 64 within the first container 54', which is then flowed into the manifold assembly 40 in the same manner as discussed above in relation to Fig. 4.
• the modified source generator -46' shown in Fig. 5 has all of the advantages of the source generator 46 shown in Fig. 4, as well as an additional advantage that the ultrasonic transducer 56 does not become contaminated with a stabilized liquid used to form a desired thin film.
• FIG. 5b there is shown another modification of the mist generating apparatus of Fig.4.
• the modification of Fig.5b is very similar to that of Fig. 4 except that the transducer 56 is suspended in the generator 46" above the stabilized liquid source rather than being sealed into the bottom wall of the container.
• a stabilized liquid source could be provided within a closed container and an appropriate carrier gas could be simply bubbled through the stabilized liquid and then flowed into the mixing chamber 40; or a spray nozzle could be used to generate a mist of a stabilized liquid source within a closed container, and an appropriate carrier gas could be flowed through the mist and into the mixing chamber 40 using an inlet and outlet port similar to the ports 60, 62 shown in Fig. 4.
• YMn0 3 An example of the sol-gel synthesis of YMn0 3 follows. 1 gm. of yttrium isopropoxide Y[OCH(CH 3 ) 2 ] 3 was mixed with 8 ml. of 2-methoxyethanol. The yttrium isopropoxide did not go into solution, but was forced into solution by the addition of approximately 25 drops (slightly over one ml.) of hydrochloric acid. 0.25 grams of manganese acetate Mn(OOCCH 3 ) 2 -H 2 0 was mixed with 5 ml. 2-meth ⁇ xyethanol. The manganese acetate would not dissolve in the 2- meth ⁇ xyethanol, but was forced into solution by the addition of approximately 10 drops of hydrochloric acid.
• the yttrium and manganese solutions were then mixed together at room temperature resulting in a slightly yellow colored solution.
• the resulting YMn0 3 solution did not form a film when spun onto a silicon wafer.
• Adding H 2 0 for hydrolysis did not improve the film-forming characteristics.
• the addition of approximately 25 drops of titanium isopropoxide (a gel former) to the yttrium manganese solution resulted in a solution which remained clear for approximately 3 hours and formed good films when spun onto a silicon wafer.
• Fig. 6 there is shown an exemplary flow chart depicting the preparation of a stabilized liquid solution of lead zirconium titanate (PZT hereinafter) to be deposited utilizing the apparatus of Figs. 1-5.
• PZT lead zirconium titanate
• steps P« -P 3 stabilized liquid precursors of titanium isopropoxide, zirconium N-propoxide and lead acetate are respectively formed utilizing 2-methoxyethanol as the common solvent of each of the precursors.
• step P 4 the stabilized solutions of titanium isopropoxide and zirconium n-propoxide are mixed, while at step P 5 such mixture is further mixed with the stabilized solution of lead acetate precursor together with dopants or additives (if any) desired in the thin film to be deposited.
• step P 6 the final mixture of P 5 is filtered to form a stock solution as shown in P r Table I below presents a more detailed analysis of steps P.*-P r
• steps P 1 through P 8 are conventional steps utilized in forming sol-gels used in conventional spin-on thin film forming procedures.
• step P p the conventional stock solution of P 7 or the conventional hydroryzed solution of P a are modified for use in the deposition processes of the present invention.
• step P 9 essentially involves adjusting the concentration of the desired chemical compound in the sol-gel, or other stabilized liquid source, such that small droplets of the vaporized source (mist) as flowed into the vacuum chamber
• the sol-gel concentration will be adjusted such that a film of the sol- gel will deposit completely over the substrate 5 before a significant amount of drying of the individual droplets occur, which would undesirably result in the creation of small disconnected particles on the substrate, the particles ultimately resulting in a thin film which is very porous and or granular.
• Determination of ihe appropriate concentration of chemical compound in the sol-gel or other stabilized liquid source involves considerations of the particular chemical compound and solvent used in the stabilized liquid source, as well as of the vacuum level maintained within the vacuum chamber 2.
• solvents having relatively high boiling points such as 2-methoxyethanol used in the PZT sol-gel discussed above, are slower to dry than solvents having relatively low boiling points such as methanol; while higher vacuum levels result in faster drying of any given stabilized liquid source.
• the stock solution of P 7 or the hydroryzed solution of P 8 will be modified in step P 9 by the addition of 10-15 percent (by volume) of methanol.
• the normal sol-gel is diluted to a sufficient degree to assure that the small droplets of the vaporized source which deposit on the substrate 5 are sufficiently fluid to spread out and interconnect to form a continuous, uniform film as discussed above.
• step P 10 the modified solution of step P 9 is vaporized using a source generator such as shown in Figs. 4 or 5, and is flowed into the deposition apparatus 1 through the manifold assembly 40 where it is deposited on the substrate 5 to form a thin film of the sol-gel.
• the thickness of the deposited thin film will be continuously monitored by conventional means (not shown).
• the substrate 5 having a thin film of the sol-gel or other stabilized liquid source thereon is subjected to vacuum to remove the solvent from the sol-gel, thus leaving a thin film of the desired chemical compound on the substrate, while at step P 12 the thin film of the chemical compound will, if necessary, be annealed.
• drying step P ⁇ r drying of the sol-gel film may alternatively be accomplished by using a heating means to bake or otherwise heat the deposited film.
• P 12 may be effected within the vacuum chamber 2 using appropriate heating means or may be performed in different apparatus outside of the vacuum chamber 2.
• the substrate having a thin film of the chemical compound thereon is further processed, such as by having a top electrode deposited thereon.
• the apparatus of the first embodiment of the present invention as discussed above in relation to Figs.1-5 is very advantageous because it effectively combines the best of vacuum, CVD, and wet chemistry (sol-gel, MOD, etc.) techniques to readily produce very complex, multi-element films in a controlled environment.
• Some specific advantages include the ability to carefully, consistently control the sto hiometiy of thin films being deposited, the relative ease with which stabilized liquid sources may be generated and handled, the ability to keep the deposited films free from contaminants (because the deposition process is operated under vacuum conditions), the ability to form very thin, uniform films fully covering a substrate surface, etc.
• the deposition process according to the invention will be conducted at room/ambient temperatures.
• an aspect of the invention is that the stabilized compound sources are agitated ultrasonically to atomize the sources before they are introduced into the process chamber. Depending upon the particular stabilized source and application, it may be desirable to heat the lines through which the vapor is introduced into the manifold assembly and/or into the process chamber.
• a solvent exchange technique arrives at a common solvent in order to produce a sol-gel or other stabilized liquid having compounds X and Y.
• the invention is advantageous in depositing complex, compound thin films of materials such as ferroelectrics, super-conductors, materials with high dielectric constants, gems, etc., but is not limited to depositing such complex thin films.

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=24649498

Family Applications (1)

Country Status (4)

Cited By (5)

Families Citing this family (1)

Citations (9)

• 1992
  • 1992-02-21 JP JP4511586A patent/JP2860505B2/ja not_active Expired - Lifetime
  • 1992-02-21 KR KR1019930702549A patent/KR100202532B1/ko not_active IP Right Cessation
  • 1992-02-21 AU AU20139/92A patent/AU2013992A/en not_active Abandoned
  • 1992-02-21 WO PCT/US1992/001380 patent/WO1992015112A1/en active Application Filing
• 1998
  • 1998-08-21 JP JP23601498A patent/JP3238663B2/ja not_active Expired - Fee Related

Patent Citations (9)

Also Published As

Similar Documents

Legal Events