Photomask

About: Photomask is a research topic. Over the lifetime, 7917 publications have been published within this topic receiving 54524 citations. The topic is also known as: photoreticle & reticle.

Semiconductor device and method of manufacturing the same

Abstract: In a semiconductor device manufacturing method includes the steps of uniformly applying a first photoresist onto a first layer on a semiconductor substrate, a first resist pattern is formed out of the first photoresist by using a first photomask. The first layer is etched by using the resist pattern, thereby forming a first pattern. A second photoresist is uniformly applied onto the semiconductor substrate where the first pattern is formed. A second resist pattern is formed out of the second photoresist by using a second photomask. The first pattern is etched by using the second photoresist, thereby forming a second pattern constituted by the first layer. A semiconductor device fabricated by this method is also disclosed.

Phase shift photomask, phase shift photomask blank, and process for fabricating them

Abstract: The invention relates to a phase shift photomask in which the peripheral region portion of a phase shift layer is removed by a relatively simple procedure and which has no or little defect and is inexpensive, a blank therefor, and a process for fabricating them. The process includes the steps of forming phase shift layer 23 all over the surface of one side of transparent substrate 21, and immersing only the peripheral region of substrate 21 in etching solution 25 to etch away the peripheral region of phase shift layer 23, whereby phase shift layer 27 is confined within an area smaller than that of substrate 21.

Study of the spatial resolution of laser thermochemical technology for recording diffraction microstructures

Abstract: The thermochemical method for recording data, which is based on local laser oxidation of a thin metal film with subsequent etching of the unirradiated region, is an alternative to laser photolithography and direct laser removal of the film material. This recording technology is characterised by the absence of thermal and hydrodynamic image distortions, as in the case of laser ablation, and the number of necessary technological operations is much smaller as compared with the photomask preparation in classical photolithography. The main field of application of the thermochemical technology is the fabrication of diffraction optical elements (DOEs), which are widely used in printers, bar-code readers, CD and DVD laser players, etc. The purpose of this study is to increase the resolution of thermochemical data recording on thin chromium films.

Apparatus for and method of correcting a defective photomask

Abstract: A defect, in a metal photomask, that is either to be etched away, if opaque, or to be rendered opaque, if light-transmitting, is corrected, with the aid of novel apparatus, in a novel method of: (a) depositing a photoresist coating over a patterned film on one surface of the photomask, (b) focusing a projected shaped beam of light, incapable of exposing the photoresist coating, onto the photoresist coating, (c) aligning the focused beam, by viewing it from a surface of the photomask opposite to that which the photoresist coating is on, so that the light overlays the defect, (d) changing the characteristics of the beam of light so as to expose the photoresist coating, and (e) developing the photoresist coating. Depending upon the kind of photoresist coating used, the defect can now be either etched away or rendered opaque.

Mask-induced best-focus shifts in deep ultraviolet and extreme ultraviolet lithography

Abstract: The mask plays a significant role as an active optical element in lithography, for both deep ultraviolet (DUV) and extreme ultraviolet (EUV) lithography. Mask-induced and feature-dependent shifts of the best-focus position and other aberration-like effects were reported both for DUV immersion and for EUV lithography. We employ rigorous computation of light diffraction from lithographic masks in combination with aerial image simulation to study the root causes of these effects and their dependencies from mask and optical system parameters. Special emphasis is put on the comparison of transmission masks for DUV lithography and reflective masks for EUV lithography, respectively. Several strategies to compensate the mask-induced phase effects are discussed.