摘要:
A method of manufacturing semiconductor structures is disclosed. In one embodiment, a first mask is provided above a substrate. The first mask includes first mask lines extending along a first axis. A second mask is provided above the first mask. The second mask includes second mask lines extending along a second axis that intersects the first axis. At least one of the first and second masks is formed by a pitch fragmentation method. Structures may be formed in the substrate, wherein the first and the second mask are effective as a combined mask. The structures may be equally spaced at a pitch in the range of a minimum lithographic feature size for repetitive line structures.
摘要:
A carrier has a surface with a mask layer thereon. An irradiation-sensitive layer on the mask layer is exposed and developed to form a first exposure structure. The first exposure structure is used as an etching mask while the mask layer is etched. The first exposure structure is subsequently removed. A second irradiation-sensitive layer is applied to the mask layer and the carrier. The second irradiation-sensitive layer is exposed with a first exposure dose and a second exposure dose. The second irradiation-sensitive layer is subsequently developed to form a second exposure structure with a first and second exposure structure thickness. The carrier is etched down to a first etching depth in the region of the first exposure structure thickness and down to a second etching depth in the region of the second exposure structure thickness. The first etching depth is larger than the second etching depth.
摘要:
A method of focus variation is described herein to achieve a one-step exposure of a wafer without the limitation of applying a complex y-tilt to a wafer stage. The position of the wafer surface to be exposed is periodically varied with respect to the focal plane, or vice versa. This relative movement between the focal plane, or best focus position along the optical axis and the wafer stage, or the wafer surface, is achieved by applying a movement to at least one of the reticle stage, one or more of the optical elements of the projection lens, and the wafer stage. The frequency of the movement is selected in dependence of the laser frequency (upper limit) or the scanning frequency (lower limit).
摘要:
A method for forming a structure element in a layer arranged on a wafer by a trimming mask set, a developing step, and an etching step for the transfer of the structure pattern are carried out between the exposure steps carried out by the masks. Consequently, edges that are incipiently exposed below a limit value for the structure formation around the resist structures in a first resist layer, which are exposed using a first mask of the set, are transferred dimensionally accurately into an underlying layer on the wafer. Then, the exposure postprocesses the pattern of the first mask using a second mask of the set, the trimming mask, into a second, subsequently applied second resist layer.
摘要:
The present invention relates to a method for producing a structure serving as an etching mask on the surface of a substrate. In this case, a first method involves forming a first partial structure on the surface of the substrate, which has structure elements that are arranged regularly and are spaced apart essentially identically. A second method involves forming spacers on the surface of the substrate, which adjoin sidewalls of the structure elements of the first partial structure, cutouts being provided between the spacers. A third method step involves introducing filling material into the cutouts between the spacers, a surface of the spacers being uncovered. A fourth method step involves removing the spacers in order to form a second partial structure having the filling material and having structure elements that are arranged regularly and are spaced apart essentially identically. The structure to be produced is composed of the first partial structure and the second partial structure.
摘要:
A semiconductor wafer is exposed with a pattern from a mask or reticle in an exposure tool. The exposure tool has an adjustable lens system and a light source, which is tunable in wavelength. A first exposure is performed with a tuned first wavelength and a first setting of the lenses. Prior to performing a second exposure onto the same wafer and into the same resist layer, the wavelength of the light source is varied to a second wavelength in order to mimic a focus offset. A resulting image shift at the slit edges of the scanning system due to chromatic aberration is then corrected for by setting the lens system in dependence of the difference between the tuned first and second wavelength. Having tuned second wavelength of the light source and having set the lens system, the second exposure is performed. A continuous adjustment of the lens system based upon a continuously varying light source wavelength can be accomplished.
摘要:
A photoresist layer on a substrate wafer is exposed in first sections with a first exposure radiation and in second sections with a second exposure radiation that is phase-shifted by 180°. The first and second sections adjoin one another in boundary regions in which the photoresist layer is artificially not sufficiently exposed. Where a distance between these boundary regions is smaller than a photolithographically critical, least distance, the photoresist layer is exposed, at a first boundary region, with a third exposure radiation and at a second boundary region with a fourth exposure radiation phase-shifted by 180°. A trim mask provided for the process has a first translucent region and a second translucent region. The first light-transparent region and the second light-transparent region are fashioned such that the light passing through the first light-transparent region and the light passing through the second light-transparent region has a phase displacement of 180°.
摘要:
The present invention relates to a method for producing a structure serving as an etching mask on the surface of a substrate. In this case, a first method involves forming a first partial structure on the surface of the substrate, which has structure elements that are arranged regularly and are spaced apart essentially identically. A second method involves forming spacers on the surface of the substrate, which adjoin sidewalls of the structure elements of the first partial structure, cutouts being provided between the spacers. A third method step involves introducing filling material into the cutouts between the spacers, a surface of the spacers being uncovered. A fourth method step involves removing the spacers in order to form a second partial structure having the filling material and having structure elements that are arranged regularly and are spaced apart essentially identically. The structure to be produced is composed of the first partial structure and the second partial structure.
摘要:
Semitransparent and trenchlike, absorber-free structure elements are formed jointly on a photomask formed using phase mask technology. The trenchlike structure elements are formed as trench or mesa structure using CPL technology. In a layout, dense, but also if appropriate semi-isolated and isolated, but relatively thin pattern portions are selected to fabricate them on the photomask using CPL technology. By contrast, isolated, wider pattern portions are formed as semitransparent structure elements using halftone phase mask technology. The respective process windows are relatively large and are adapted to one another. The joint process window is enlarged. In the area of dynamic memory chips, structures in a memory cell array can be formed using CPL technology and the support regions using halftone phase mask technology. In logic circuits, thin conductor tracks using CPL technology and wider conductor tracks using halftone phase mask technology can be fabricated.
摘要:
A method is provided for improving a photolithographic simulation model of the photolithographic simulation of a pattern formed on a photomask. Proceeding from a two-dimensional simulation model that takes account of the physical-chemical processes during lithography, a frequency-dependent intensity loss is calculated which is determined by multiplication of the simulated intensity distribution in the Fourier space by a filter function. An accurate calculation of the intensity distribution in the substrate plane is obtained. This method achieves the accuracy of three-dimensional models with a significantly shorter processing duration and is further suitable in particular for the calculation of OPC structures.