Phase-shift mask

About: Phase-shift mask is a research topic. Over the lifetime, 2088 publications have been published within this topic receiving 18058 citations.

Development of advanced reticle inspection apparatus for hp 65 nm node device and beyond

Abstract: The usage of ArF immersion lithography for hp 65nm node and beyond leads to the increase of mask error enhancement factor in the exposure process. Wavelength of inspection tool is required to consistent with wavelength of lithography tool. Wavelength consistency becomes more important by the introduction of phase shift mask such as Tri-tone mask and alternating phase shift mask. Therefore, mask inspection system, whose inspection light wavelength is 199nm, has been developed. This system has transmission and reflection inspection mode, and throughput, using 70 nm pixel size, were designed within 2hours per mask. The experimental results show expected advantages for Die-to-Die and Die-to-Database inspection compared with the system using 257nm inspection optics. Shorter wavelength effect makes transmission inspection sensitivity increase, and realizes 40nm size particle inspection. As for the phase shift mask, the difference of gray value between the area with phase defect and without phase defect was clear relatively. In this paper, specifications and design, experimental results are described.

Phaseshift mask and manufacturing the same

Abstract: The present invention provides a method of manufacturing halftone phase shift masks in less steps to save time and cost and to increase the yield, and a halftone phase shift mask with higher phase—and size controllability. To achieve this, the halftone phase shift mask includes a structure having a shade band of resist film formed on the halftone film delineating fine patterns and around the area of fine pattern.

Large-area high-quality photomasks

Abstract: The LRS family of laser scanning pattern generators with stages 600 by 600, 800 by 800, and 1100 by 1100 mm, a selection of optical resolutions, and lasers for chrome and photographic emulsion cover the complete range of precision large-area masks. The first large-area system was delivered in 1992, and there are now 11 systems installed or on order for applications ranging from precision metal etching to shadow masks and high-end chrome masks for AMLCDs and field-effect displays. These writers match the requirements for the next generation of large screen printers. It is technically feasible to build a full-field projection printer with resolution and geometrical corrections similar to those of a stepper, but with no stitching or intra-field distortion. The pattern quality would be that of the mask and higher productivity would result. The combined experience of masks for flat panels and shadow masks makes the LRS system well characterized for visual display applications. In particular all systematic errors visible in the finished displays are suppressed to very low levels. The LRS writers satisfy the needs for high-quality large-area photomasks, including masks for AMLCDs.

Optimization of laser machining process for the preparation of photomasks, and its application to microsystems fabrication

Abstract: Conventional photolithography normally utilizes a photomask for patterning light onto a chemical resist film. Therefore, the accuracy of microfabrication is highly dependent on the accuracy of the photomasks. Fabrication of hard masks involves the use of expensive laser pattern generators and other sophisticated machines using very high-precision stages and the necessary control instrumentation; therefore, an inexpensive strategy is highly necessary for laboratory-level fabrication. As this technology is primarily based on raster scanning of a laser beam, the mask making as such becomes a low-throughput process. A strategy of high-throughput manufacturing of hard masks with laser micromachining using a one-step exposure process of a chromated glass slide through a micromachined aluminum shadow mask is proposed. The features that are finally embedded in the mask are highly demagnified and well focused. Optimization of the laser machining process is carried out by considering all processing parameters. The features are characterized using an optical microscope, a scanning electron microscope, and a self-developed image analysis code. Geometrical methods are used to estimate the average edge roughness and feature size. We have also validated the usage of these masks by performing microfabrication on films made of photoresist.

Method for fabricating phase shift mask

Abstract: Methods of fabricating phase shift masks, which facilitate easy adjustment of the light transmissivity of a field region and the thickness of a phase shift mask, to thereby simplify the production process, and increase its reliability and performance. Embodiments may include the steps of providing a transparent substrate, forming a conductive light shielding layer on the transparent substrate, implanting oxygen ions into the conductive light shielding layer to form a semitransparent film, and selectively etching the semitransparent film to form a phase shift film.