Abstract: A microwave heating device includes a variable frequency microwave power supply, a waveguide launcher, and a fixture to contain a material to be heated, with the fixture located directly adjacent to the end of the launcher. All heating occurs in the near-field region, i.e., no cavity modes or standing waves are established within the fixture. This condition may be insured by keeping the thickness of the fixture or workpiece under one wavelength (at all microwave frequencies being used). The launcher is preferably a horn configured to spread the microwave power laterally over a selected area while maintaining a single propagating mode. The invention may be used to enhance catalytic reactions for research and other purposes. Alternatively, the invention may be configured to perform spot curing or repair operations involving adhesives and composites.

Abstract: A microwave heating device includes a variable frequency microwave power supply, a waveguide launcher, and a fixture to contain a material to be heated, with the fixture located directly adjacent to the end of the launcher. All heating occurs in the near-field region. This condition may be insured by keeping the thickness of the fixture or workpiece under one wavelength (at all microwave frequencies being used). The launcher is preferably a horn or waveguide configured to apply the microwave power to a small area to perform spot curing or repair operations involving adhesives and composites. The spot curing may secure components in place for further handling, after which a thermal or oven treatment will cure the remaining adhesive to develop adequate strength for service. A related method is also disclosed.

Abstract: A microwave heating device includes a variable frequency microwave power supply, a waveguide launcher, and a fixture to contain a material to be heated, with the fixture located directly adjacent to the end of the launcher. All heating occurs in the near-field region, i.e., no cavity modes or standing waves are established within the fixture. This condition may be insured by keeping the thickness of the fixture or workpiece under one wavelength (at all microwave frequencies being used). The launcher is preferably a horn configured to spread the microwave power laterally over a selected area while maintaining a single propagating mode. The invention may be used to enhance catalytic reactions for research and other purposes. Alternatively, the invention may be configured to perform spot curing or repair operations involving adhesives and composites.

Abstract: An apparatus for thermal treatment of dielectric films on substrates includes: a microwave applicator cavity and microwave power source; a workpiece to be heated in the cavity, having a porous coating on a selected substrate; and, an apparatus for introducing a controlled amount of a polar species into the porous coating immediately before heating by the microwave power. The interaction of the polar species with the microwaves enhances the efficiency of the process, to shorten process time and reduce thermal budget. A related method includes: depositing a porous film on a substrate; soft baking the film to a selected state of dryness; introducing a controlled amount of a polar species into the soft baked film; and, applying microwave energy to heat the film via interaction with the polar species.

Abstract: A microwave heating device includes a variable frequency microwave power supply, a waveguide launcher, and a fixture to contain a material to be heated, with the fixture located directly adjacent to the end of the launcher. All heating occurs in the near-field region. This condition may be insured by keeping the thickness of the fixture or workpiece under one wavelength (at all microwave frequencies being used). The launcher is preferably a horn or waveguide configured to apply the microwave power to a small area to perform spot curing or repair operations involving adhesives and composites. The spot curing may secure components in place for further handling, after which a thermal or oven treatment will cure the remaining adhesive to develop adequate strength for service.

Abstract: A microwave heating device includes a variable frequency microwave power supply, a waveguide launcher, and a fixture to contain a material to be heated, with the fixture located directly adjacent to the end of the launcher. All heating occurs in the near-field region. This condition may be insured by keeping the thickness of the fixture or workpiece under one wavelength (at all microwave frequencies being used). The launcher is preferably a horn or waveguide configured to apply the microwave power to a small area to perform spot curing or repair operations involving adhesives and composites. The spot curing may secure components in place for further handling, after which a thermal or oven treatment will cure the remaining adhesive to develop adequate strength for service. A related method is also disclosed.

Abstract: A microwave heating device includes a variable frequency microwave power supply, a waveguide launcher, and a fixture to contain a material to be heated, with the fixture located directly adjacent to the end of the launcher. All heating occurs in the near-field region, i.e., no cavity modes or standing waves are established within the fixture. This condition may be insured by keeping the thickness of the fixture or workpiece under one wavelength (at all microwave frequencies being used). The launcher is preferably a horn configured to spread the microwave power laterally over a selected area while maintaining a single propagating mode. The invention may be used to enhance catalytic reactions for research and other purposes. Alternatively, the invention may be configured to perform spot curing or repair operations involving adhesives and composites.

Abstract: A microwave heating device includes a variable frequency microwave power supply, a waveguide launcher, and a fixture to contain a material to be heated, with the fixture located directly adjacent to the end of the launcher. All heating occurs in the near-field region, i.e., no cavity modes or standing waves are established within the fixture. This condition may be insured by keeping the thickness of the fixture or workpiece under one wavelength (at all microwave frequencies being used). The launcher is preferably a horn configured to spread the microwave power laterally over a selected area while maintaining a single propagating mode. The invention may be used to enhance catalytic reactions for research and other purposes. Alternatively, the invention may be configured to perform spot curing or repair operations involving adhesives and composites.

Abstract: A microwave processing system includes: a broadband variable frequency microwave (VFM) source; a plurality of waveguide applicators, each of which includes a waveguide transition and is capable of supporting a selected subset of frequencies within the bandwidth of the broadband VFM source; a microwave switching means allowing the microwave source to be connected to any one of the waveguide transitions so that microwave power is delivered to the corresponding waveguide applicator; and wherein each of the waveguide applicators includes at least one channel through which a microwave transparent tube may be run so that process fluid flowing through the tube may be exposed to microwave power in the applicator.

Abstract: A microwave heating device includes a variable frequency microwave power supply, a waveguide launcher, and a fixture to contain a material to be heated, with the fixture located directly adjacent to the end of the launcher. All heating occurs in the near-field region, i.e., no cavity modes or standing waves are established within the fixture. This condition may be insured by keeping the thickness of the fixture or workpiece under one wavelength (at all microwave frequencies being used). The launcher is preferably a horn configured to spread the microwave power laterally over a selected area while maintaining a single propagating mode. The invention may be used to enhance catalytic reactions for research and other purposes. Alternatively, the invention may be configured to perform spot curing or repair operations involving adhesives and composites.

Abstract: A multilayer structure comprises: a substrate; and, a plurality of polymerizable layers successively deposited on the substrate, with each successive layer having a greater dielectric polarizability than the preceding layer(s), so that each successive layer will absorb microwave energy preferentially to the preceding layer(s). In this way, successive layers can be cured without over-curing the preceding layers. The individual layers are preferably materials from a single chemical family (e.g., epoxies, polyimides, PBO, etc.) and have similar properties after curing. The dielectric polarizabilities may be adjusted by modifying such factors as chain endcap dipole strength, cross-linker dipole strength, promoter, solvent, and backbone type. The invention is particularly suitable for producing various polymer layers on silicon for electronic applications. An associated method is also disclosed.

Abstract: An apparatus for processing battery electrodes includes: a microwave applicator cavity with slots on opposite ends to allow a continuous sheet to move through the cavity in a first direction; a processing chamber constructed of microwave-transparent material, disposed within the applicator cavity and surrounding the continuous sheet, the processing chamber having slots to allow the continuous sheet to pass through it; a microwave power supply to deliver power to the applicator cavity; a source of heated gas providing a controlled gas flow through the processing chamber in a direction opposite the first direction; and, at least one non-contacting temperature measuring device positioned to measure a surface temperature at a selected location on the continuous sheet as it passes through the processing chamber. The apparatus is particularly suited for removing polar solvents from porous electrode coatings. A related method is also disclosed.

Abstract: An apparatus for processing battery electrodes includes: a microwave applicator cavity with slots on opposite ends to allow a continuous sheet to move through the cavity in a first direction; a processing chamber constructed of microwave-transparent material, disposed within the applicator cavity and surrounding the continuous sheet, the processing chamber having slots to allow the continuous sheet to pass through it; a microwave power supply to deliver power to the applicator cavity; a source of heated gas providing a controlled gas flow through the processing chamber in a direction opposite the first direction; and, at least one non-contacting temperature measuring device positioned to measure a surface temperature at a selected location on the continuous sheet as it passes through the processing chamber. The apparatus is particularly suited for removing polar solvents from porous electrode coatings. A related method is also disclosed.

Abstract: An apparatus for thermal treatment of dielectric films on substrates includes: a microwave applicator cavity and microwave power source; a workpiece to be heated in the cavity, having a porous coating on a selected substrate; and, an apparatus for introducing a controlled amount of a polar species into the porous coating immediately before heating by the microwave power. The interaction of the polar species with the microwaves enhances the efficiency of the process, to shorten process time and reduce thermal budget. A related method includes: depositing a porous film on a substrate; soft baking the film to a selected state of dryness; introducing a controlled amount of a polar species into the soft baked film; and, applying microwave energy to heat the film via interaction with the polar species.

Abstract: A method for making a lithium-ion cell includes depositing an electrode material as a coating on a substrate of the lithium-ion cell, irradiating the deposited electrode material with microwave radiation of varying frequency, wetting the irradiated electrode material with a non-aqueous electrolyte solution, and sealing the wetted electrode material in an air-tight enclosure.

Abstract: An apparatus for thermal treatment of dielectric films on substrates includes: a microwave applicator cavity and microwave power source; a workpiece to be heated in the cavity, having a porous coating on a selected substrate; and, an apparatus for introducing a controlled amount of a polar species into the porous coating immediately before heating by the microwave power. The interaction of the polar species with the microwaves enhances the efficiency of the process, to shorten process time and reduce thermal budget. A related method includes: depositing a porous film on a substrate; soft baking the film to a selected state of dryness; introducing a controlled amount of a polar species into the soft baked film; and, applying microwave energy to heat the film via interaction with the polar species.

Abstract: A method for curing photosensitive polyimide (PSPI) films includes the steps of: depositing a PSPI film on a selected substrate, and curing the film by microwave heating at a selected temperature from about 200 to 340° C. in a selected atmosphere containing an oxygen concentration from about 20 to 200,000 ppm. The process atmosphere may be static or flowing. The addition of oxygen improves the removal of acrylate residue and improves the Tg of the cured film, while the low processing temperature characteristic of the microwave process prevents the oxygen from damaging the polyimide backbone. The method may further include the steps of photopatterning and developing the PSPI film prior to curing. The process is particularly suitable for dielectric films on silicon for electronic applications.

Abstract: A microwave heating device includes a variable frequency microwave power supply, a waveguide launcher, and a fixture to contain a material to be heated, with the fixture located directly adjacent to the end of the launcher. All heating occurs in the near-field region. This condition may be insured by keeping the thickness of the fixture or workpiece under one wavelength (at all microwave frequencies being used). The launcher is preferably a horn or waveguide configured to apply the microwave power to a small area to perform spot curing or repair operations involving adhesives and composites. The spot curing may secure components in place for further handling, after which a thermal or oven treatment will cure the remaining adhesive to develop adequate strength for service. A related method is also disclosed.

Abstract: An apparatus for heating a semiconductor wafer includes: a microwave source; an applicator cavity; and, a fixture for supporting a wafer in the cavity. The fixture includes a dielectric mechanical support for the wafer and a grounded metallic ring movably positioned parallel to and concentric with the wafer at some distance from the wafer, to adjust the microwave power distribution to compensate for edge effects. A closed-loop feedback system adjusts the distance based on wafer edge and center temperatures. A method for heating a semiconductor wafer includes: a. placing the wafer in a microwave cavity; b. supporting the wafer on a fixture comprising a dielectric wafer support and a grounded metallic ring movably positioned at some distance from the wafer; c. introducing microwave power into the cavity to heat the wafer; and d. adjusting the distance between wafer and ring to modify the power distribution near the wafer edge.

Abstract: A microwave heating device includes a variable frequency microwave power supply, a waveguide launcher, and a fixture to contain a material to be heated, with the fixture located directly adjacent to the end of the launcher. All heating occurs in the near-field region, i.e., no cavity modes or standing waves are established within the fixture. This condition may be insured by keeping the thickness of the fixture or workpiece under one wavelength (at all microwave frequencies being used). The launcher is preferably a horn configured to spread the microwave power laterally over a selected area while maintaining a single propagating mode. The invention may be used to enhance catalytic reactions for research and other purposes. Alternatively, the invention may be configured to perform spot curing or repair operations involving adhesives and composites.