Journal ArticleDOI
Improving resolution in photolithography with a phase-shifting mask
Reads0
Chats0
TLDR
The phase-shifting mask as mentioned in this paper consists of a normal transmission mask that has been coated with a transparent layer patterned to ensure that the optical phases of nearest apertures are opposite.Abstract:
The phase-shifting mask consists of a normal transmission mask that has been coated with a transparent layer patterned to ensure that the optical phases of nearest apertures are opposite. Destructive interference between waves from adjacent apertures cancels some diffraction effects and increases the spatial resolution with which such patterns can be projected. A simple theory predicts a near doubling of resolution for illumination with partial incoherence σ < 0.3, and substantial improvements in resolution for σ < 0.7. Initial results obtained with a phase-shifting mask patterned with typical device structures by electron-beam lithography and exposed using a Mann 4800 10X tool reveals a 40-percent increase in usuable resolution with some structures printed at a resolution of 1000 lines/mm. Phase-shifting mask structures can be used to facilitate proximity printing with larger gaps between mask and wafer. Theory indicates that the increase in resolution is accompanied by a minimal decrease in depth of focus. Thus the phase-shifting mask may be the most desirable device for enhancing optical lithography resolution in the VLSI/VHSIC era.read more
Citations
More filters
Journal ArticleDOI
Pushing the limits of lithography
Takashi Ito,Shinji Okazaki +1 more
TL;DR: Although the introduction of shorter-wavelength light sources and resolution-enhancement techniques should help maintain the current rate of device miniaturization for several more years, a point will be reached where optical lithography can no longer attain the required feature sizes.
Journal ArticleDOI
Novel cold cathode materials and applications
Ningsheng Xu,S. Ejaz Huq +1 more
TL;DR: In this article, a review of field emission cold cathode materials has been presented, focusing on several kinds of novel cold cathodes that have been developed in the past decade, including materials for microfabricated field-emitter arrays, diamond and related films, carbon nanotubes, other quasi one-dimensional nanomaterials and printable composite materials.
Journal ArticleDOI
Lithography and Other Patterning Techniques for Future Electronics
TL;DR: In this paper, the authors focus on the benefits of using ICs at the 22-nm node and beyond, and no shortage of ideas on how to accomplish this, although it is not clear that optics will be the most economical in this range; extreme ultraviolet is still the official front runner, and electron beam lithography, which has demonstrated minimum features less than 10 nm wide, continues to be developed both for mask making and for directly writing on the wafer (also known as ldquomaskless lithographyrdquo).
Patent
Phase shifting circuit manufacture method and apparatus
Yao-Ting Wang,Yagyensh C. Pati +1 more
TL;DR: In this article, the phase shift mask and the single phase structure mask are derived from a set of masks used in a larger minimum dimension process technology and used for shrinking integrated circuit designs.
Lithography and Other Patterning Techniques for Future Electronics As integrated circuits continue to go smaller, laying down circuit patterns on semiconductor material becomes more expensive and new techniques are needed.
R. Fabian Pease,Stephen Y. Chou +1 more
TL;DR: The benefits of continuing to be able to manufacture electronics at the 22-nm node and beyond appear to justify the investment, and there is no shortage of ideas on how to accomplish this.
References
More filters
Book
Introduction to Fourier optics
TL;DR: The second edition of this respected text considerably expands the original and reflects the tremendous advances made in the discipline since 1968 as discussed by the authors, with a special emphasis on applications to diffraction, imaging, optical data processing, and holography.
Journal ArticleDOI
Partially coherent imaging in two dimensions and the theoretical limits of projection printing in microfabrication
TL;DR: In this article, the authors quantitatively studied the optical projection printing with a diffracted image of two bars of equal width and space and an aspect ratio of three, using the four-dimensional integral for partially coherent imaging.