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.

Phase shift mask blank, phase shift mask, and method for manufacturing phase shift mask blank

Abstract: A phase shift mask blank having, on a transparent substrate, a phase shift film including, as main components, a metal, silicon (Si) and nitrogen (N), having optical characteristics of a transmittance of equal to or greater than 9% and equal to or less than 30% with respect to a wavelength of the ArF excimer laser beam and a phase difference of equal to or greater than 150° and less than 180°, and a light-shielding film formed on the phase shift film. A thickness of the phase shift film is equal to or less than 80 nrn, a refractive index (n) with respect to the wavelength of the ArF excimer laser beam is equal to or greater than 2.3, and an extinction coefficient (k) is equal to or greater than 0.28.

Method of phase shift mask fabrication comprising a tapered edge and phase conflict resolution

Abstract: A method for forming a phase shifting photomask is provided. The method includes forming a transparent substrate having a pattern of opaque features and determining areas of phase conflicts between the features. Phase shifters having a tapered edge are formed on selected portions of the features in the phase conflict areas while the remaining portion of the features remain unprotected. During a subsequent lithographic process using the photomask, the tapered edges of the phase shifters spread out the electric field so that an image corresponding to the tapered edges does not print at the target. This permits the phase shifters to be located without the constraints of an alternating aperture pattern. The phase shifters can be formed using an additive process in which a phase shift layer is deposited over the opaque features or using a subtractive process in which the substrate subjacent to the opaque features is etched.

Phase shift mask blank and phase shift mask

Abstract: PROBLEM TO BE SOLVED: To provide a halftone phase shift mask which has desired optimum optical characteristics with high accuracy and which can suppress changes in the optical characteristics due to cleaning or the like when the mask is manufactured and used SOLUTION: The halftone phase shift mask blank has a light semi-transmitting film consisting of a thin film made of a substance containing metal, silicon and oxygen and/or nitrogen as main structural elements on a transparent substrate In the light semi-transmitting film, changes in the composition is recognized in a region from the surface to 100 Å depth, the total proportion of Si and O in the surface layer from the surface to 20 Å depth is ≥80 atm%, and the total proportion of Si and O in a region deeper than the above surface layer of the semi-transmitting film is smaller than in the surface layer COPYRIGHT: (C)2005,JPO&NCIPI

Optical properties of hydrogenated amorphous-carbon film for attenuated phase-shift mask applications

Abstract: The optical properties of a plasma‐deposited amorphous‐carbon film have been investigated in the ultraviolet (365 nm) and deep ultraviolet range (248 nm). By varying process conditions, the optical transmission through the films was tuned from 4% to 20% at 365 nm and from 3% to 9% at 248 nm. This tuneability was related to the hydrogen content of the film as affected by the process parameters. The index of refraction n measured by spectroscopic ellipsometry is ∼2 at the wavelengths used. These optical properties make this film attractive for use in single layer attenuated phase‐shift masks for potential application in 0.25 μm lithography at 365 and 248 nm.

Enhancements in rigorous simulation of light diffraction from phase-shift masks

Abstract: With the increasing importance of phase-shift masks (PSM), the rigorous simulation of the light diffraction from the mask becomes a standard technique in lithography simulation. The combination of rigorous simulation of light diffraction with scalar and vector imaging theory results in several possible model options. The paper presents an overview about these model options. A new approach to the modeling of oblique incidence of light on the mask is proposed. The performance of field decomposition techniques for two selected examples is discussed. The different model options are applied to the simulation of the imaging of an alternating PSM with a ArF scanner. Resist simulations are performed with a calibrated model. Simulation results are verified experimentally and presented via resist imaging data for different pitches.