Showing papers by "Satoshi Nagai published in 2009"

Exposure method and semiconductor device manufacturing method

Abstract: In an exposure method, an anti-reflection film and a photoresist are stacked in order on the surface of a substrate. A periodic pattern of a pitch P is formed on a pattern surface of a photomask. A medium having a refractive index n is present between a projection lens having a numerical aperture NAp and the substrate. The refractive index, coefficient of extinction and thickness of the anti-reflection film are selected so that the reflectance of exposure light of a wavelength λ at an interface between the photoresist and the anti-reflection film is less than or equal to a desired value when an angle of incidence θ is within a range determined by λ/P−NAp≦n×sin θ≦NAp. The angle of incidence θ is formed to a perpendicular line in the medium by light incident on the surface of the substrate.

Exposure method, mask data producing method, and semiconductor device manufacturing method

Abstract: An exposure method has irradiating a mask with light based on an exposure performing condition, a first mask pattern and a second mask pattern being formed in the mask, and projecting images of the first mask pattern and second mask pattern onto a wafer through a projection lens, a lower-layer film material and a photoresist being sequentially laminated on the wafer, wherein the exposure performing condition is a condition on which, when exposure is performed on a predetermined exposure condition, the predetermined exposure condition is adjusted such that a difference between a wafer position at which a best focus is obtained for the image of the first mask pattern and a wafer position at which a best focus is obtained for the image of the second mask pattern falls within a predetermined range, the wafer position of the first mask pattern and the wafer position of the second mask pattern being predicted using film thicknesses and optical characteristics of the photoresist and the lower-layer film material.

Method for manufacture of semiconductor device

Abstract: A semiconductor device manufacturing method includes designing a resist structure including a film having antireflection function for exposure light and a resist on the film to be formed on a substrate, designing an exposure condition of the resist obtained by exposing and developing the resist such that a resist pattern is finished as designed, obtaining criteria value for estimating influence of a resist pattern upon a dimension or shape of a device pattern, the resist pattern being obtained by exposing the resist under the designed exposure condition and developing the exposed resist, the device pattern being obtained by etching the resist structure using the resist pattern as a mask, determining whether the designed exposure condition is acceptable or not based on the criteria value, and redesigning the exposure condition of the resist without changing the designed resist structure when the designed exposure condition is determined not acceptable.

Design of resist stacks with antireflection coatings from the viewpoint of focus budget

Abstract: Liquid immersion lithography tools with NA=1.3 are being applied for hp4x node device and beyond. As the typical DOF has been reduced to 100 nm or less for this hyper-NA exposure, precise consideration of the error factors that lead to DOF reduction is required. The BFD (Best Focus Difference between pattern kinds) induced by resist stack is one of the error factors yet to be solved. In this work, the BFD induced by resist stack was studied through simulation and experiment by decomposing it into the following three components: One induced by the "refraction" effect, one induced by the "reflection" effect and one induced by the "process" effect. Each BFD was evaluated by simulation to make a BFD budget. Experimental verification was also performed, which confirmed BFD of 25 nm and it was found that over 30 % of the observed BFD was induced owing to resist stack. Based on this result, we discuss a method for controlling the BFD by utilizing projection lens aberration and review the design flow of resist stacks with antireflection coatings.

Eddy current flaw detecting probe, eddy current flaw detecting device, and eddy current flaw detection method

Abstract: PROBLEM TO BE SOLVED: To provide an eddy current flaw detecting probe capable of circumventing reduction in the reliability of detecting defects resulting from a defect-forming state, without having an operation of arrangement change, driving control, or the like, of an excitation coil accompany it. SOLUTION: This eddy current flaw detecting probe comprises an excitation coil group consisting of a first excitation coil 11, a second excitation coil 12, and a third excitation coil 13 for inducing eddy current in a flaw detecting object such as a metallic conduit 20, and a detecting coil 14 for detecting the variation in the eddy current generated in a part of the defect 21, such as, cracks in the flaw detecting object. The center axes of respective excitation coils are set in the mutually different directions. Then, the direction of composite eddy current obtained by vector-composing eddy currents E1, E2 and E3 induced by the excitation coil group is made variable, by strength control of current supplied to each excitation coil, and the composite eddy current sufficiently varies, with respect to various forming states of the defect 21. COPYRIGHT: (C)2009,JPO&INPIT

Method for evaluating flare in exposure tool

Abstract: A method for evaluating flare of an exposure tool has measuring a first reference integral exposure amount of illumination light emitted from the light source, and a unit reference integral exposure amount of illumination light emitted from the light source, the first reference integral exposure amount being required for the first evaluation pattern to be developed on the photosensitive film, the unit reference integral exposure amount being required for the first effective exposure region to be developed on the photosensitive film; calculating a first evaluation value by dividing the unit reference integral exposure amount by the first reference integral exposure amount; and evaluating a total flare amount of the illuminating optical system and the projecting optical system, using the first evaluation value.

Method of controlling exposure device, method of fabricating semiconductor, and photomask

Abstract: A method of controlling exposure device according to an embodiment includes preparing a photomask in which a check pattern is formed, wherein the check pattern comprising a plurality of patterns which have a first diameter and a second diameter and have pattern dimensions being changeable after being transferred according to polarization degree of exposure light are arranged in the second diameter direction, irradiating the photomask with the exposure light having a predetermined polarization degree so as to transfer the check pattern to a transferred object, and measuring the dimensions of the images of the check pattern transferred to the transferred object so as to obtain the polarization degree.