Ionizing radiation has been found to be widely applicable in modifying the structure and properties of polymers, and can be used to tailor the performance of either bulk materials or surfaces. Fifty years of research in polymer radiation chemistry has led to numerous applications of commercial and economic importance, and work remains active in the application of radiation to practical uses involving polymeric materials. This paper provides a survey of radiation-processing methods of industrial interest, ranging from technologies already commercially well established, through innovations in the active R&D stage which show exceptional promise for future commercial use. Radiation-processing technologies are discussed under the following categories: cross-linking of plastics and rubbers, curing of coatings and inks, heat-shrink products, fiber–matrix composites, chain-scission for processing control, surface modification, grafting, hydrogels, sterilization, natural product enhancement, plastics recycling, ceramic precursors, electronic property materials, ion-track membranes and lithography for microdevice production. In addition to new technological innovations utilizing conventional gamma and e-beam sources, a number of promising new applications make use of novel radiation types which include ion beams (heavy ions, light ions, highly focused microscopic beams and high-intensity pulses), soft X-rays which are focused, coherent X-rays (from a synchrotron) and e-beams which undergo scattering to generate patterns.

High-energy radiation and polymers: A review of commercial processes and emerging applications

Lithography is a field in which advances proceed at a swift pace. This book was written to address several needs, and the revisions for the second edition were made with those original objectives in mind. Many new topics have been included in this text commensurate with the progress that has taken place during the past few years, and several subjects are discussed in more detail. This book is intended to serve as an introduction to the science of microlithography for people who are unfamiliar with the subject. Topics directly related to the tools used to manufacture integrated circuits are addressed in depth, including such topics as overlay, the stages of exposure, tools, and light sources. This text also contains numerous references for students who want to investigate particular topics in more detail, and they provide the experienced lithographer with lists of references by topic as well. It is expected that the reader of this book will have a foundation in basic physics and chemistry. No topics will require knowledge of mathematics beyond elementary calculus.

Principles of Lithography

A lithographic apparatus configured to project a patterned beam of radiation onto a target portion of a substrate is disclosed. The apparatus includes a first radiation dose detector and a second radiation dose detector, each detector comprising a secondary electron emission surface configured to receive a radiation flux and to emit secondary electrons due to the receipt of the radiation flux, the first radiation dose detector located upstream with respect to the second radiation dose detector viewed with respect to a direction of radiation transmission, and a meter, connected to each detector, to detect a current or voltage resulting from the secondary electron emission from the respective electron emission surface.

Lithographic apparatus, and device manufacturing method

Extreme ultraviolet lithography (EUVL) was thoroughly reviewed over a broad range of topics, including history, tools, source, metrology, condenser and projection optics, resists, and masks. Since 1988, many studies on EUVL have been conducted in North America, Europe, and Japan, through state sponsored programs and industrial consortiums. To date, no “show stopper” has been identified, but challenges are present in almost all aspects of EUVL technology. Commercial alpha lithography step-and-scan tools are installed with full-field capability; however, EUVL power at intermediate focus (IF) has not yet met volume manufacturing requirements. Compared with the target of 180W IF power, current tools can supply only approximately 55–62W. EUV IF power has been improved gradually from xenon- to tin-discharge-produced plasma or laser-produced plasma. EUVL resist has improved significantly in the last few years, with 25nm 1:1 line/space resolution being produced with approximately 2.7nm (3σ) line edge roughness. A...

Extreme ultraviolet lithography: A review

An extreme ultraviolet light source apparatus has a magnetic field generator which generates a magnetic field region around a direction of the magnetic field passing through a plasma region in which a plasma is to be generated and converges charged particles including ion emitted from the plasma region toward the direction of the magnetic field, a first charged particle collector (receiver) mounted at both sides of an axis of the magnetic field in the magnetic field region in order to collect (receive) the charged particles converged by the magnetic field, a target supply unit supplying a target from a nozzle located outside a converging region in which the charged particles are to be converged inside the magnetic field region in an extreme ultraviolet light generating chamber, and a target collector located at a position opposite to the nozzle, the target retrieval portion retrieving a residual target which does not contribute to generation of the plasma.

Extreme ultraviolet light source apparatus

An extreme ultraviolet lithography (EUVL) machine or system for producing integrated circuit (IC) components, such as transistors, formed on a substrate. The EUVL machine utilizes a laser plasma point source directed via an optical arrangement onto a mask or reticle which is reflected by a multiple mirror system onto the substrate or target. The EUVL machine operates in the 10-14 nm wavelength soft x-ray photon. Basically the EUV machine includes an evacuated source chamber, an evacuated main or project chamber interconnected by a transport tube arrangement, wherein a laser beam is directed into a plasma generator which produces an illumination beam which is directed by optics from the source chamber through the connecting tube, into the projection chamber, and onto the reticle or mask, from which a patterned beam is reflected by optics in a projection optics (PO) box mounted in the main or projection chamber onto the substrate. In one embodiment of a EUVL machine, nine optical components are utilized, with four of the optical components located in the PO box. The main or projection chamber includes vibration isolators for the PO box and a vibration isolator mounting for the substrate, with the main or projection chamber being mounted on a support structure and being isolated.

Extreme ultraviolet lithography machine

Control of particle contamination on the reticle and carbon contamination of optical surfaces in photolithography systems can be achieved by the establishment of multiple pressure zones in the photolithography systems. The different zones will enclose the reticle, projection optics, wafer, and other components of system. The system includes a vacuum apparatus that includes: a housing defining a vacuum chamber; one or more metrology trays situated within the vacuum chamber each of which is supported by at least one support member, wherein the tray separates the vacuum chamber into a various compartments that are maintained at different pressures; and conductance seal devices for adjoining the perimeter of each tray to an inner surface of the housing wherein the tray is decoupled from vibrations emanating from the inner surface of the housing.

Extreme-UV lithography vacuum chamber zone seal

A system for improving vision that can diagnose monochromatic aberrations within a subject's eyes, apply the wavefront correction, and then enable the patient to view the results of the correction. The system utilizes a laser for producing a beam of light; a corrector; a wavefront sensor; a testing unit; an optic device for directing the beam of light to the corrector, to the retina, from the retina to the wavefront sensor, and to the testing unit; and a computer operatively connected to the wavefront sensor and the corrector.

Adaptive ophthalmologic system

A prototype high-speed tape target transport is constructed for use in a high-repetition-rate laser plasma source. To reduce plasma debris, a 1000–5000-A-thick film of target material is supported by thin Mylar tape backing. Tape is transported to the laser focal volume at a maximum velocity of 356 cm/s, a rate sufficient to accommodate laser repetition rates of 1 kHz. The transport is fully vacuum compatible and can be retracted and then isolated from the laser plasma vacuum enclosure during tape reel replacement. The operating characteristics of the transport are described.

Prototype high-speed tape target transport for a laser plasma soft-x-ray projection lithography source

: The feasibility of producing small feature sizes in resists using soft x-ray projection lithography has been demonstrated. Experiments by AT and T Bell Laboratories have achieved features small as 0.05 microns using a Schwarzschild objective and 140 angstrom radiation from an undulator at the National Synchrotron Light Source. We describe here a similar imaging system in which the illumination is derived from a high-fluence laser plasma source (LPS) of soft x-rays instead of a synchrotron radiation source. The laser plasma source has been shown to be a useful illumination source for soft x-ray microscopy.

Steven J. Haney

Papers

Extreme ultraviolet lithography machine

Extreme-UV lithography vacuum chamber zone seal

Adaptive ophthalmologic system

Prototype high-speed tape target transport for a laser plasma soft-x-ray projection lithography source

Soft-X-Ray Projection Imaging Using a Laser Plasma Source,