Intel Corporation

Renesas Technology Corp.

Dai Nippon Printing Co., Ltd.

Yoshihiro Tezuka

Masaaki Ito

Toshihiko Tanaka

Tsuneo Terasawa

Wilman Tsai

Charles W Holzwarth

Toshifumi Yokoyama

Jeff N Farnsworth

Fred T Chen

Tsukasa Abe

Ping Qu

Steven Labovitz

Marieke Ordway

Adam Seeger

The present disclosure is directed to a EUV mask measurement tool having a source assembly that generates a high power extreme ultraviolet (EUV) light beam, a detector assembly including a projection optics system and a CCD camera, a stage for supporting a patterned mask, the pattern mask including a plurality of predetermined test sites, a processor programmed to determine a site specific best focus plane for each of the plurality of predetermined test sites on the patterned mask, and a program module to generate instructions to move the stage to the best focus plane for each of the plurality of predetermined test sites on the patterned mask. In addition, a method for generating a site specific best focus plane for each of the plurality of predetermined test sites using a continuous scanning process that provides a continuous image output from the test site.

Measurement tool and method for lithography masks

The present disclosure is directed to EUV mask inspection tools including a source assembly that generates a EUV beam, a detector assembly having a projection optics system, a processor, a movable stage supporting a patterned mask, a stage control system, and a processor programmed to set the height for the stage based on instructions of a first program module that analyzes and combines mask pattern data and mask layout information to generate an out-of-plane distortion map. In an aspect, a second program module generates instructions to analyze inspection results outputted by the inspection tool to generate a defocus characterization map. In a further aspect, a present method provides predictive data and actual measured data to determine stage heights for use by a present mask inspection tool for inspection of patterned EUV masks to obtain results that compensate for defocusing to due to bowing of the patterned EUV mask.

Measurement tool and methods for EUV lithography masks

An embodiment of the present invention is a technique to inspect defects in mask blanks. A first iris diaphragm is located at an illumination source to limit an illumination angle of light emitted from the illumination source. A scattering limit unit is located at exit of a dark field optical unit to limit scattering angle of the light scattered after reflecting from a mask blank. A defect analyzer is optically coupled to the dark field optical unit to generate an angular distribution of the scattered light. The angular distribution is used to characterize criticality of a defect found on the mask blank.

Detecting and characterizing mask blank defects using angular distribution of scattered light

Defect detection is performed with two settings, that is, setting of a focus position where a signal intensity obtained from a dot pattern is maximum and setting of a focus position where a signal intensity obtained from a hole pattern is maximum. In addition, defect detection is performed at a predetermined focus position previously set and for the detected defect, the focus position is changed at that position to find a focus position where the signal intensity is maximum. If the focus position is away from a signal light-receiving system, the defect is determined as dot-shaped. If the focus position is close to the signal light-receiving system, the defect is determined as hole-shaped. If the focus position is intermediate of them, the defect is determined as an elongated-shaped.

Method and system of defect inspection for mask blank and method of manufacturing semiconductor device using the same

Embodiments include determining whether defects exist in an extreme ultraviolet (EUV) light mask blank. Incident EUV light scattered or diffused by abnormalities in the layers of the mask blank may be measured, normalized, and compared to threshold values to determine if and where a defect exists. Normalizing may be performed by dividing a light intensity value for a pixel by the average of light intensity values for one or more rings of surrounding pixels. A defect may be determined by considering whether the normalized intensity value for a pixel is greater than a pixel threshold to identify the pixel is a candidate for a location with a defect; and by determining whether the sum of normalized light intensity values for a block of pixels including the pixel satisfies a pixel block threshold to determine whether the block scatters or diffuses a critical amount of light to identify a defect.

Mask blanks inspection tool

Mask blanks inspection method and mask blank inspection tool

The invention provides methods and apparatuses for controlling critical dimension (CD) uniformity of a photomask by neutralizing CD variation associated with pattern density and process fluctuation.

Method and apparatus for photomask fabrication

A method is described comprising depositing a layer of resist on a mask substrate having transparent and opaque layers. The resist layer is then exposed to radiation. The radiation is patterned to produce features within an active device area and a moat surrounding the active device area. The radiation is also controlled to have a differential increased incident energy in the moat area of the mask compared to the active device area. Specifically, the exposure dose applied to the moat is greater than that normally required to completely remove the resist during the developing stage. The magnitude of the additional exposure dose is empirically derived and is based upon such factors as the type of resist and the thickness of the resist.

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Tsukuba, Japan

Yoshihiro Tezuka