Abstract: A photomask pattern on a substrate is provided. The photomask pattern comprises a main pattern and a sub-resolution assistant feature. The sub-resolution assistant feature is located on the sides of the main pattern. Furthermore, the sub-resolution assistant feature comprises a first assistant feature and a second assistant feature. The first assistant feature is formed close to the main pattern and the second assistant feature is formed further away from the main pattern but adjacent to the first assistant feature. There is a phase difference of 180° between the first assistant feature and the main pattern. Similarly, there is a phase difference of 180° between the second assistant feature and the first assistant feature. Since the main pattern is bordered by reverse-phase assistant feature, exposure resolution of the photomask is increased.

Abstract: A chrome-less mask inspection method is provided. The chrome-less mask at least includes a transparent region and a phase shift region. The method includes providing a database having a mask database corresponding to the chrome-less mask. The mask database further includes a frame line pattern having enclosed area and pattern that corresponds to enclosed area and pattern of the phase shift region of the chrome-less mask and a first inspection signal pattern generated by the mask database. An inspecting device is also provided to inspect a second inspection signal pattern from the chrome-less mask. Furthermore, scanning location of the second inspection signal pattern corresponds with scanning location of the first inspection signal pattern. Thereafter, the first inspection signal pattern and the second inspection signal pattern is compared and any differences are registered.

Abstract: A phase shift mask includes a transparent substrate, a semi-dense pattern, and a dense pattern. The semi-dense pattern is formed on the transparent substrate including a plurality of phase shift regions and non-phase shift regions arranged successively. The dense pattern is formed on the transparent substrate including a plurality of non-phase shift regions, phase shift regions, and non-transparent regions.

Abstract: The present invention relates to a photolithography process using hybrid chromeless phase shift masks. A mask having a gate pattern formed on a base plate is provided. A 180-degree shifter layer is formed at critical dimension locations of the base plate. The mask of the present invention can be used for transferring the gate pattern to a photoresist layer in the exposure process.

Abstract: The method includes performing phase shift mask correction to the main feature through the wafer. The method utilized an assistant feature such as a mixed of chromeless pattern and chrome pattern to correct the pattern. In one case, the assistant feature with chrome utilized to correct the feature pattern to simplify the CAD manufacturing. On the other hand, the feature pattern with chrome is used to replace the feature pattern with chromeless to correct the pattern with large critical dimensional such that the small chromeless pattern will not be used during the mask manufacturing and the occurring probability of defect will be improved.

Abstract: An optical proximity correction method that uses additional corner serifs or hammerhead pattern to correct and avoid pull up of ends in a main pattern. These corner serifs are set such that the main pattern is corrected with only a slight line-end width expansion and line-end approaching the original design in length. Since the optical proximity correction method is able to correct the main pattern so that the end approaches the original design after a photo-exposure, any misalignment that may lead to uncompleted contact or an open of metallic interconnects can be avoided. Furthermore, the slightly expanded end permits a higher process window in the fabrication of metallic interconnects.

Abstract: An unlanded process for manufacturing semiconductor circuits. Optical proximity correction of the electrical connection region of a conductive line is carried out to increase the area so that alignment accuracy between the conductive line and a via/contact improves. Optical proximity correction of the photomask for forming a conductive line pattern is carried out by first determining the electrical connection regions in the conductive line pattern. The regions are expanded equi-directionally or extended outward direction along the edges of the conductive line to form magnified regions. Overlapping regions between the original conductive line pattern and the magnified regions, regions outside the conductive line pattern as well as regions too close to neighboring conductive line pattern are removed. The final magnified regions and the original conductive line pattern are combined to obtain an optical proximity corrected photomask.

Abstract: In a method of optical proximity correction, a main pattern is provided. The main pattern has a critical dimension. When the critical dimension is reduced to reach or fall below a first reference value, a serif/hammerhead is added onto the main pattern. When the critical dimension is further reduced to a second reference value or below, an assist feature is added onto the main pattern. The corrected pattern is then transferred to a layer on the wafer with an improved fidelity.

Abstract: An optical proximity correction method. Assist features, such as scattering bars, are added to a main pattern to be transferred. Calculations are performed on the entire two-dimensional original pattern using model-based optical proximity correction. A series of features are added according to the specific reference indexes of the coordinate system. The original pattern is altered to form a corrected pattern. The process of calculation and correction, however, does not include the scattering bars.

Abstract: A contact hole model-based optical proximity correction method. The method includes building a contact hole model from the database obtained through a series of test patterns each having a plurality of contact holes of different line widths but identical distance of separation. Line width offsets due to proximity effect are eliminated by referring to the contact hole model.

Abstract: An unlanded process for manufacturing semiconductor circuits. Optical proximity correction of the electrical connection region of a conductive line is carried out to increase the area so that alignment accuracy between the conductive line and a via/contact improves. Optical proximity correction of the photomask for forming a conductive line pattern is carried out by first determining the electrical connection regions in the conductive line pattern. The regions are expanded equi-directionally or extended outward direction along the edges of the conductive line to form magnified regions. Overlapping regions between the original conductive line pattern and the magnified regions, regions outside the conductive line pattern as well as regions too close to neighboring conductive line pattern are removed. The final magnified regions and the original conductive line pattern are combined to obtain an optical proximity corrected photomask.

Abstract: A contact hole model-based optical proximity correction method. The method includes building a contact hole model from the database obtained through a series of test patterns each having a plurality of contact holes of different line widths but identical distance of separation. Line width offsets due to proximity effect are eliminated by referring to the contact hole model.

Abstract: An optical proximity correction method that uses additional corner serifs or hammerhead pattern to correct and avoid pull up of ends in a main pattern. These corner serifs are set such that the main pattern is corrected with only a slight line-end width expansion and line-end approaching the original design in length. Since the optical proximity correction method is able to correct the main pattern so that the end approaches the original design after a photo-exposure, any misalignment that may lead to uncompleted contact or an open of metallic interconnects can be avoided. Furthermore, the slightly expanded end permits a higher process window in the fabrication of metallic interconnects.

Abstract: A phase shift mask for photolithography used in fabricating integrated circuits is disclosed. The mask comprises a transparent plate and a first opaque film formed on said transparent plate, which has a first pattern defining a main feature region. The first pattern is then imaged onto a photoresist layer coated on a wafer for the integrated circuits. The present invention further comprises at least one phase shift region formed on said transparent plate to correspond to an active region of the wafer, in which the phase shift region is used to improve optical scattering effect of the first pattern through the active region while performing the photolithography. Moreover, the present invention comprises at least one second opaque film formed on said transparent plate to correspond to a non-active region of the wafer, in which each has at least one second pattern used to improve optical scattering effect of the first pattern through the non-active region while performing the photolithography.

Abstract: A method of optical proximity correction suitable for use in a mixed mode photomask. An original pattern is to be transferred from the mixed mode photomask. A binary mask curve and a phase shift mask curve reflecting relationship between critical dimensions of the photomask and the original pattern are obtained. A critical value of the critical dimension is selected. For the binary mask curve, the portion with the critical dimension of the original pattern larger than the critical value is selected. In contrast, for the phase shift mask curve, the portion with the critical dimension of the original pattern smaller than the critical value is selected. These two portions are combined as an optical characteristic curve. The mixed mode photomask can thus be fabricated according to the optical characteristic curve.

Abstract: In a method of optical proximity correction, a main pattern is provided. The main pattern has a critical dimension. When the critical dimension is reduced to reach or fall below a first reference value, a serif/hammerhead is added onto the main pattern. When the critical dimension is further reduced to a second reference value or below, an assist feature is added onto the main pattern. The corrected pattern is then transferred to a layer on the wafer with an improved fidelity.

Abstract: A loudspeaker system includes at least two loudspeaker units. Each loudspeaker unit includes at least one loudspeaker mechanism mounted on a loudspeaker enclosure. The loudspeaker enclosure includes an outer cabinet body having an open front side, a closed rear side, opposed lateral walls, and opposed top and bottom walls, and an inner baffle frame disposed in the cabinet body. The baffle frame has parallel left and right walls that form a sound space in the baffle frame. The left and right walls further form first clearances with the lateral walls respectively, and have a front portion with the loudspeaker mechanism mounted thereon. The front portion cooperates with the lateral walls to form a pair of acoustic port openings at front ends of the first clearances. The left and right walls further have a rear portion that forms a second clearance with the rear side. The second clearance is communicated with and extends between rear ends of the first clearances.

Abstract: A half-tone phase shift mask is formed from the composite structure of a mask substrate and a half-tone phase shifting layer. The half-tone phase shifting layer induces a 180° phase shift to light passing through the mask. The half tone phase shifting layer further includes a main pattern having a first width and a first length, and an assist feature having a second width and a second length. The assist feature is parallel to the main pattern and disposed at both sides of the main pattern while being separated therefrom by a distance. Using deep ultraviolet light as the exposure source, a wafer scale of the first width is about 0.1-0.15 &mgr;m, a wafer scale of the second width is about 0.055-0.09 &mgr;m and the distance between the main pattern and the assist feature is about 0.22-0.27 &mgr;m.

Abstract: A reticle having an assist feature between semi-dense lines is described. The reticle has two adjacent, substantially parallel, and substantially equally spaced line segments of which each representing a portion of a main feature having a line width, between two adjacent line segments of the group having a gap space, wherein the gap-space/line-width ratio is equal to about 3-6.5. Between the two adjacent line segments, at least one inside assist feature is located. At the outside edges of the extreme left-hand and right-hand line segments, two outside assist features are located, respectively, wherein each of the two assist features has a first width and is spaced apart from the nearest line segment by a distance.

Abstract: A method of optical proximity correction. A main pattern is provided. The main pattern has a critical dimension. When the critical dimension is reduced to reach a first reference value or below, a serif/hammerhead is added onto the main pattern. When the critical dimension is further reduced to a second reference value or below, an assist feature is added onto the main pattern. The corrected pattern is then transferred to a layer on wafer with an improved fidelity.