Patents by Inventor Chien M. Wai
Chien M. Wai has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20080136028Abstract: The invention includes a method of forming a metal-containing film over a surface of a semiconductor substrate. The surface is exposed to a supercritical fluid. The supercritical fluid has H2, at least one H2-activating catalyst, and at least one metal-containing precursor dispersed therein. A metal-containing film is formed across the surface of the semiconductor substrate from metal of the at least one metal-containing precursor. The invention also includes semiconductor constructions having metal-containing layers which include one or more of copper, cobalt, gold and nickel in combination with one or more of palladium, platinum, iridium, rhodium and ruthenium.Type: ApplicationFiled: October 25, 2002Publication date: June 12, 2008Inventors: Chien M. Wai, Hiroyuki Ohde, Steve Kramer
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Publication number: 20080134837Abstract: Embodiments of a method and a system for recovering a metal, such as uranium, from a metal-containing material are disclosed. The metal-containing material is exposed to an extractant containing a liquid or supercritical-fluid solvent and an acid-base complex including an oxidizing agent and a complexing agent. Batches of the metal-containing material are moved through a series of stations while the extractant is moved through the stations in the opposite direction. After the extraction step, the metal is separated from the solvent, the complexing agent and/or other metals by exposing the extract to a stripping agent in a countercurrent stripping column. The complexing agent and the solvent exit the column and are separated from each other by reducing the pressure. The recovered complexing agent is recharged with fresh oxidizing agent and recombined with fresh or recovered solvent to form a recovered extractant, which is distributed through the extraction stations.Type: ApplicationFiled: January 12, 2006Publication date: June 12, 2008Applicant: IDAHO RESEARCH FOUNDATION, INC.Inventors: Chien M. Wai, Sydney S. Koegler
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Publication number: 20080115627Abstract: A method for separating metals from metal-containing materials by extraction without generating large quantities of liquid waste is disclosed. Also disclosed is an extractant composition for use with this method. The method comprises exposing a metal-containing material to a solvent, such as supercritical carbon dioxide, an acid-base complex, and a chelating agent that is not a component of the acid-base complex. The metal is released into the solvent by a combination of oxidation by an oxidizing agent in the acid-base complex and chelation by the chelating agent. The oxidizing agent in the acid-base complex is solubilized by a solubilizing agent. The disclosed method and composition have many applications and are particularly well suited for the extraction of transition metals, including, but not limited to, platinum group metals, nom a metals and coinage metals. Applications include the recovery of metals from scrap materials and the planarization of semiconductor structures.Type: ApplicationFiled: August 18, 2005Publication date: May 22, 2008Inventors: Joanna S. Wang, Chien M. Wai
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Patent number: 7341947Abstract: The invention includes a method of forming a metal-containing film over a surface of a semiconductor substrate. The surface is exposed to a supercritical fluid. The supercritical fluid has H2, at least one H2-activating catalyst, and at least one metal-containing precursor dispersed therein. A metal-containing film is formed across the surface of the semiconductor substrate from metal of the at least one metal-containing precursor. The invention also includes semiconductor constructions having metal-containing layers which include one or more of copper, cobalt, gold and nickel in combination with one or more of palladium, platinum, iridium, rhodium and ruthenium.Type: GrantFiled: May 25, 2004Date of Patent: March 11, 2008Assignee: Micron Technology, Inc.Inventors: Chien M. Wai, Hiroyuki Ohde, Steve Kramer
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Patent number: 7128840Abstract: Improved methods for the extraction or dissolution of metals, metalloids or their oxides, especially lanthanides, actinides, uranium or their oxides, into supercritical solvents containing an extractant are disclosed. The disclosed embodiments specifically include enhancing the extraction or dissolution efficiency with ultrasound. The present methods allow the direct, efficient dissolution of UO2 or other uranium oxides without generating any waste stream or by-products.Type: GrantFiled: March 25, 2003Date of Patent: October 31, 2006Assignee: Idaho Research Foundation, Inc.Inventors: Chien M. Wai, Youichi Enokida
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Patent number: 6653236Abstract: The invention includes a method of forming a metal-containing film over a surface of a semiconductor substrate. The surface is exposed to a supercritical fluid. The supercritical fluid has H2, at least one H2-activating catalyst, and at least one metal-containing precursor dispersed therein. A metal-containing film is formed across the surface of the semiconductor substrate from metal of the at least one metal-containing precursor. The invention also includes semiconductor constructions having metal-containing layers which include one or more of copper, cobalt, gold and nickel in combination with one or more of palladium, platinum, iridium, rhodium and ruthenium.Type: GrantFiled: March 29, 2002Date of Patent: November 25, 2003Assignee: Micron Technology, Inc.Inventors: Chien M. Wai, Hiroyuki Ohde, Steve Kramer
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Publication number: 20030183938Abstract: The invention includes a method of forming a metal-containing film over a surface of a semiconductor substrate. The surface is exposed to a supercritical fluid. The supercritical fluid has H2, at least one H2-activating catalyst, and at least one metal-containing precursor dispersed therein. A metal-containing film is formed across the surface of the semiconductor substrate from metal of the at least one metal-containing precursor. The invention also includes semiconductor constructions having metal-containing layers which include one or more of copper, cobalt, gold and nickel in combination with one or more of palladium, platinum, iridium, rhodium and ruthenium.Type: ApplicationFiled: March 29, 2002Publication date: October 2, 2003Inventors: Chien M. Wai, Hiroyuki Ohde, Steve Kramer
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Publication number: 20030183043Abstract: Improved methods for the extraction or dissolution of metals, metalloids or their oxides, especially lanthanides, actinides, uranium or their oxides, into supercritical solvents containing an extractant are disclosed. The disclosed embodiments specifically include enhancing the extraction or dissolution efficiency with ultrasound. The present methods allow the direct, efficient dissolution of UO2 or other uranium oxides without generating any waste stream or by-products.Type: ApplicationFiled: March 25, 2003Publication date: October 2, 2003Inventors: Chien M. Wai, Youichi Enokida
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Patent number: 6524628Abstract: Pressurized Water Extraction (PWE) is a method for extracting materials from plants by exposing a plant sample to a pressurized liquid aqueous composition. The exposure may be performed statically, dynamically, or both. For example, the sample may be exposed to a liquid aqueous composition at a temperature of from about 0° C. to about 100° C. and a pressure between about 25 atm and about 1000 atm, more typically from about 50 atm to about 200 atm. Plant materials are selectively isolated in the aqueous compositions by this method more effectively than prior methods. Moreover, the present methods provide facile extraction of thermally labile compounds, such as bilobalides from Gingko leaves.Type: GrantFiled: November 6, 2000Date of Patent: February 25, 2003Assignee: Idaho Research Foundation, Inc.Inventors: Chien M. Wai, Qingyong Lang
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Patent number: 6187911Abstract: A method for separating a desired metal or metalloi from impurities using a supercritical extraction process based on solubility differences between the components, as well as the ability to vary the solvent power of the supercritical fluid, is described. The use of adduct-forming agents, such as phosphorous-containing ligands, to separate metal or metalloid chelates in such processes is further disclosed. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is selected from the group consisting of &bgr;-diketones; phosphine oxides, such as trialkylphosphine oxides, triarylphosphine oxides and alkylarylphosphine oxides; phosphinic acids; carboxylic acids; phosphates, such as trialkylphosphates, triarylphosphates and alkylarylphosphates; crown ethers; dithiocarbamates; phosphine sulfides; phosphorothioic acids; thiophosphinic acids; halogenated analogs of these chelating agents; and mixtures of these chelating agents.Type: GrantFiled: May 7, 1999Date of Patent: February 13, 2001Assignee: Idaho Research Foundation, Inc.Inventors: Chien M. Wai, Neil G. Smart, Cindy Phelps
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Patent number: 6132491Abstract: A method for dissociating metal-ligand complexes in a supercritical fluid by treating the metal-ligand complex with heat and/or reducing or oxidizing agents is described. Once the metal-ligand complex is dissociated, the resulting metal and/or metal oxide form fine particles of substantially uniform size. In preferred embodiments, the solvent is supercritical carbon dioxide and the ligand is a .beta.-diketone such as hexafluoroacetylacetone or dibutyldiacetate. In other preferred embodiments, the metals in the metal-ligand complex are copper, silver, gold, tungsten, titanium, tantalum, tin, or mixtures thereof. In preferred embodiments, the reducing agent is hydrogen. The method provides an efficient process for dissociating metal-ligand complexes and produces easily-collected metal particles free from hydrocarbon solvent impurities. The ligand and the supercritical fluid can be regenerated to provide an economic, efficient process.Type: GrantFiled: August 20, 1998Date of Patent: October 17, 2000Assignee: Idaho Research Foundation, Inc.Inventors: Chien M. Wai, Fred H. Hunt, Neil G. Smart, Yuehe Lin
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Patent number: 6117413Abstract: The invention pertains to compounds which specifically bind radionuclides, and to methods of making radionuclide complexing compounds. In one aspect, the invention includes a radionuclide delivery system comprising: a) a calix[n]arene-crown-[m]-ether compound, wherein n is an integer greater than 3, and wherein m is an integer greater than 3, the calix[n]arene-crown-[m]-ether compound comprising at least two ionizable groups; and b) an antibody attached to the calix[n]arene-crown-[m]-ether compound.Type: GrantFiled: November 12, 1997Date of Patent: September 12, 2000Assignees: Battelle Memorial Institute, Idaho Research Foundation, Inc.Inventors: Darrell R. Fisher, Chien M. Wai, Xiaoyuan Chen
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Patent number: 6075130Abstract: The invention pertains to compounds for binding lanthanide ions and actinide ions. The invention further pertains to compounds for binding radionuclides, and to methods of making radionuclide complexes. Also, the invention pertains to methods of extracting radionuclides. Additionally, the invention pertains to methods of delivering radionuclides to target locations. In one aspect, the invention includes a compound comprising: a) a calix[n]arene group, wherein n is an integer greater than 3, the calix[n]arene group comprising an upper rim and a lower rim; b) at least one ionizable group attached to the lower rim; and c) an ion selected from the group consisting of lanthanide and actinide elements bound to the ionizable group.Type: GrantFiled: November 10, 1998Date of Patent: June 13, 2000Assignees: Battelle Memorial Institute, Idaho Research Foundation, Inc.Inventors: Xiaoyuan Chen, Chien M. Wai, Darrell R. Fisher
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Patent number: 5965025Abstract: A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent is described. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated .beta.-diketone. In especially preferred embodiments the extraction solvent is supercritical carbon dioxide, and the chelating agent comprises a fluorinated .beta.-diketone and a trialkyl phosphate, or a fluorinated .beta.-diketone and a trialkylphosphine oxide. Although a trialkyl phosphate can extract lanthanides and actinides from acidic solutions, a binary mixture comprising a fluorinated .beta.-diketone and a trialkyl phosphate or a trialkylphosphine oxide tends to enhance the extraction efficiencies for actinides and lanthanides.Type: GrantFiled: January 21, 1998Date of Patent: October 12, 1999Assignee: Idaho Research Foundation, Inc.Inventors: Chien M. Wai, Kenneth E. Laintz
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Patent number: 5840193Abstract: Methods for extracting metalloid and metal species from a solid or liquid material by exposing the material to a fluid solvent, particularly supercritical CO.sub.2, and a chelating agent are described. The chelating agent forms a chelate with the species, the chelate being soluble in the fluid to allow removal of the species from the material. In preferred embodiments the extraction solvent is supercritical CO.sub.2 and the chelating agent comprises an organophosphorous chelating agent, particularly sulfur-containing organophosphorous chelating agents, including mixtures of chelating agents. Examples of chelating agents include monothiophosphinic acid, di-thiophosphinic acid, phosphine sulfite, phosphorothioic acid, and mixtures thereof. The method provides an environmentally benign process for removing metal and metalloids from industrial waste solutions, particularly acidic solutions.Type: GrantFiled: July 26, 1996Date of Patent: November 24, 1998Assignee: Idaho Research FoundationInventors: Neil G. Smart, Chien M. Wai, Yuehe Lin, Yak Hwa Kwang
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Patent number: 5792357Abstract: A method of extracting metal and metalloid species from a solid or liquid substrate using a supercritical fluid solvent containing one or more chelating agents followed by back-extracting the metal and metalloid species from the metal and metalloid chelates formed thereby. The back-extraction acidic solution is performed utilizing an acidic solution. Upon sufficient exposure of the metal and metalloid chelates to the acidic solution, the metal and metalloid species are released from the chelates into the acid solution, while the chelating agent remains in the supercritical fluid solvent. The chelating agent is thereby regenerated and the metal and metalloid species recovered.Type: GrantFiled: July 26, 1996Date of Patent: August 11, 1998Assignee: Idaho Research Foundation, Inc.Inventors: Chien M. Wai, Neil G. Smart, Yuehe Lin
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Patent number: 5770085Abstract: A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a fluid solvent, particularly supercritical carbon dioxide, containing a chelating agent is described. The chelating agent forms chelates that are soluble in the fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent comprises a trialkyl phosphate, a triaryl phosphate, a trialkylphosphine oxide, a triarylphosphine oxide, or mixtures thereof. The method provides an environmentally benign process for removing contaminants from industrial waste. The method is particularly useful for extracting actinides from acidic solutions, and the process can be aided by the addition of nitrate salts. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process.Type: GrantFiled: June 2, 1995Date of Patent: June 23, 1998Assignee: Idaho Research Foundation, Inc.Inventors: Chien M. Wai, Neil G. Smart, Yuehe Lin
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Patent number: 5730874Abstract: A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent is described. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated .beta.-diketone. In especially preferred embodiments the extraction solvent is supercritical carbon dioxide, and the chelating agent comprises a fluorinated .beta.-diketone and a trialkyl phosphate, or a fluorinated .beta.-diketone and a trialkylphosphine oxide. Although a trialkyl phosphate can extract lanthanides and actinides from acidic solutions, a binary mixture comprising a fluorinated .beta.-diketone and a trialkyl phosphate or a trialkylphosphine oxide tends to enhance the extraction efficiencies for actinides and lanthanides.Type: GrantFiled: June 2, 1994Date of Patent: March 24, 1998Assignee: Idaho Research Foundation, Inc.Inventors: Chien M. Wai, Kenneth E. Laintz
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Patent number: 5606724Abstract: A method of extracting metals directly from metal oxides by exposing the oxide to a supercritical fluid solvent containing a chelating agent is described. Preferably, the metal is an actinide or a lanthanide. More preferably, the metal is uranium, thorium or plutonium. The chelating agent forms chelates that are soluble in the supercritical fluid, thereby allowing direct removal of the metal from the metal oxide. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is selected from the group consisting of .beta.-diketones, halogenated .beta.-diketones, phosphinic acids, halogenated phosphinic acids, carboxylic acids, halogenated carboxylic acids, and mixtures thereof. In especially preferred embodiments, at least one of the chelating agents is fluorinated. The method provides an environmentally benign process for removing metals from metal oxides without using acids or biologically harmful solvents.Type: GrantFiled: November 3, 1995Date of Patent: February 25, 1997Assignee: Idaho Research Foundation, Inc.Inventors: Chien M. Wai, Neil G. Smart, Cindy Phelps
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Patent number: 5356538Abstract: A method of extracting metalloid and metal species from a solid or liquid material by exposing the material to a supercritical fluid solvent containing a chelating agent. The chelating agent forms chelates that are soluble in the supercritical fluid to allow removal of the species from the material. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is a fluorinated or lipophilic crown ether or fluorinated dithiocarbamate. The method provides an environmentally benign process for removing contaminants from industrial waste without using acids or biologically harmful solvents. The chelate and supercritical fluid can be regenerated, and the contaminant species recovered, to provide an economic, efficient process.Type: GrantFiled: October 21, 1991Date of Patent: October 18, 1994Assignee: Idaho Research Foundation, Inc.Inventors: Chien M. Wai, Kenneth Laintz