Infineon Technologies Ag

Qimonda Ag

Carl Zeiss Sms Ltd.

Siemens Aktiengesellschaft

Advanced Mask Technology Center Gmbh + Co. Kg

Rainer Pforr

Mario Hennig

Molela Moukara

Uwe Griesinger

Christoph Friedrich

Fritz Gans

Jörg Thiele

Frank-Michael Kamm

Burkhard Ludwig

Wolfgang Dettmann

Nicolo Morgana

Roderick Köhle

Thomas Muelders

Karsten Zeiler

Dominique Savignac

Andreas Grassmann

Dietrich Widmann

Vladimir Dmitriev

Christoph Noelscher

Guy Ben-Zvi

Roderick Koehle

Erez Graitzer

J&ouml;rg Thiele

J&uuml;rgen Knobloch

Christian Crell

Michael Heissmeier

Hans-Georg Froehlich

Werner Fischer

Stefan Gruss

Manuel Vorwerk

Gerd Unger

Markus Hofsäss

Wilhelm Maurer

Detlef Hofmann

Carla Byloos

Marco Ahrens

Jürgen Knobloch

Haiko Rolff

Klaus Ergenzinger

Guido Thielscher

Ralf Neubauer

Bernd Kuechler

The invention relates to a method for determining a critical dimension variation of a photolithographic mask which comprises (a) using layout data of the photolithographic mask to determine at least two sub-areas of the photolithographic mask, each sub-area comprising a group of features, (b) measuring a distribution of a transmission of each sub-area, (c) determining a deviation of the transmission from a mean transmission value for each sub-area, (d) determining a constant specific for each sub-area, and (e) determining the critical dimension variation of the photolithographic mask by combining for each sub-area the deviation of the transmission and the sub-area specific constant.

Method and apparatus for determining a critical dimension variation of a photolithographic mask

A photo mask having a first set of patterns and a second set of patterns is provided in which the first set of patterns correspond to a circuit pattern to be fabricated on a wafer, and the second set of patterns have dimensions such that the second set of patterns do not contribute to the circuit pattern that is produced using a lithography process based on the first set of patterns under a first exposure condition. The critical dimension distribution of the photo mask is determined based on the second set of patterns that do not contribute to the circuit pattern produced using the lithography process based on the first set of patterns under the first exposure condition.

Lithographic targets for uniformity control

A method for minimizing errors of a plurality of photolithographic masks that serve for successively processing a substrate is provided. The method includes determining a reference displacement vector field, in which the reference displacement vector field correlates displacement vectors of the errors of the plurality of photolithographic masks. The method includes determining for each of the photolithographic mask a difference displacement vector field as a difference between the reference displacement vector field and the displacement vectors of the errors of the respective photolithographic mask, and correcting the errors for each of the photolithographic masks using the respective difference displacement vector field.

Method and apparatus for minimizing overlay errors in lithography

A lithographic mask comprises a first layer including grooves, a second layer including regions, sections and a groove-like structure that encloses the sections. The first and second layers are formed so as to reduce electrical potential differences within the second layer. A method of forming a lithographic mask includes forming first and second layers to dispose the second layer over the first layer, patterning the second layer to comprise sections, a region, and a groove-like structure enclosing the sections, and forming grooves in the first layer at portions not covered by the second layer. The first and second layers are formed to reduce potential differences within the second layers during the step of forming the grooves in the first layer.

Lithographic mask and method of forming a lithographic mask

Embodiments relate to compensating for lens heating, lithographic projection system and photo mask. Accordingly, lens heating is compensated by providing a layout pattern including a regular pattern being arranged substantially symmetrical in a first region and a sub-resolution pattern including a plurality of sub-resolution structural elements, wherein the sub-resolution pattern in a second region, so as to minimize non-homogenous lens heating of a projection apparatus in case of a lithographic projection.

Methods of compensating lens heating, lithographic projection system and photo mask

A layout is decomposed into partial patterns. An intermediate mask is drawn for each of the partial patterns. The intermediate masks are used in a mask stepper or scanner progressively for projection again into a common pattern on a test mask. A line width distribution LB(x,y) is determined from the test mask or from a test wafer exposed using the mask, and is converted into a distribution of dose corrections. The transmission T(x,y) of the respective intermediate masks is adapted based upon the calculated dose correction. This can be achieved using additional optical elements which are assigned to the intermediate masks and have shading structure elements, or by laser-induced rear-side introduction of shading elements in the quartz substrate of the intermediate masks themselves.

Method for producing a mask for the lithographic projection of a pattern onto a substrate

A reflection mask that includes a structure () for lithographically transferring a layout onto a target substrate, in particular for use in EUV lithography, and a reflective multilayer structure (). At least one flare reduction layer () is at least partly arranged on a bright field of the multilayer structure ().

Reflection mask, use of the reflection mask and method for fabricating the reflection mask

A system for projecting a pattern from a mask onto a substrate comprises a radiation source for emitting a light beam in the extreme ultraviolet wavelength range, a mask including absorbent and reflective structures forming the pattern, a collector mirror and an illumination optical system forming a first part of a beam path in order to direct the light beam onto the mask to produce a patterned light beam, a projection optical system including an arrangement of reflective mirrors forming a second part of the beam path in order to focus the reflected light beam from the mask onto the substrate, and an optical element arranged in the beam path and including at least two regions having different degrees of reflection or transmission. First and second of the regions are assigned to respective different first and second positions on the mask and/or collector mirror in accordance with the beam path.

System and method for projecting a pattern from a mask onto a substrate

A method for reducing an overlay error of structures of a layer to be patterned relative to those of a reference layer includes formation of standard measurement marks assigned to one another in the two layers for determining an overlay error and for setting up further measurement marks for determining an additional optical imaging error of the projection system at least in the current layer. The further measurement marks have a geometry adapted to the geometry of selected structures of the circuit patterns to be transferred by projection from masks onto semiconductor substrates. An imaging error affects circuit structures and further measurement marks in the same way. An alignment correction for a subsequent exposure can be calculated from the measured positional deviations between the two standard measurement marks and between the standard measurement mark and the further measurement mark of the layer currently to be patterned.

Method for reducing an overlay error and measurement mark for carrying out the same

A set of at least two masks, coordinated with one another, for the projection of structure patterns, into the same photosensitive layer arranged on a semiconductor wafer. The first mask includes a semitransparent or nontransparent first layer, which is arranged on a first substrate and in which at least one first opening is formed at a first position, the first opening having a first lateral dimension, which is greater than the resolution limit of a projection system for the projection of the structure patterns. The second mask includes a semitransparent or nontransparent second layer, which is arranged on a second substrate and in which at least one dummy structure assigned to the first opening is formed at a second position, the dummy structure having a second lateral dimension, which is smaller than the resolution limit of the projection system wherein the first position on the first mask corresponds to the second position on the second mask.

Set of at least two masks for the projection of structure patterns

A set of at least two masks for the projection of structure patterns coordinated with one another by a projection system into the same photosensitive layer of a semiconductor wafer, in which the set of at least two masks includes a primary mask having an opaque structure element, which is formed at a first position on the first mask. A second mask of the set, for example a trimming mask, which is assigned to the first mask, can have a semitransparent region assigned to the structure element of the first mask. The semitransparent region can be formed at the same position on the second mask as the opaque structure element on the first mask. With the aid of the suitable choice of the transparency of the semitransparent region, it is possible to enable an undesirable resist region to be trimmed away for enlargement of a process window during exposure of the photosensitive layer on the semiconductor wafer.

Set of masks including a first mask and a second trimming mask with a semitransparent region having a transparency between 20% and 80% to control diffraction effects and obtain maximum depth of focus for the projection of structure patterns onto a semiconductor wafer

A lithography mask has an angled structure element (O) formed by a first opaque segment (O) and by a second opaque segment (O). The structure element has at least one reflex angle (&#x3b1;). The angled structure element (O) includes at least one convex section (A) facing the reflex angle (&#x3b1;). At least one transparent structure (T) adjacent to the angled structure element (O) is provided at the convex section (A) of the angled structure element (O). The transparent structure (T) is formed in separated fashion at the convex section (A) of the angled structure element (O) and thus comprises two distinguishable transparent segments (T, T) formed at least in sections essentially axially symmetrically with respect to the angle bisector (WH) of the reflex angle.

Lithography mask for imaging of convex structures

An improvement of the imaging quality with simultaneous transfer of line-space gratings and peripheral structures including a MUX space is achieved using a quadrupole illumination whose poles are formed in elongate fashion and whose longitudinal axes are arranged perpendicular to the orientation of the lines of the line-space grating arranged on a mask. The structure imaging of the line-space grating is improved with regard to contrast, MEEF, and process window, while the geometrical fidelity of the peripheral structure, in particular of the MUX space, is stabilized over a wide depth of field range.

Apparatus for projecting a pattern into an image plane

Auxiliary openings are assigned to openings on a mask to be transferred to a wafer. These auxiliary openings have a phase-shifting property, preferably between 160&#xb0; and 200&#xb0; with respect to the openings, and a cross section lying below the limiting dimension for the printing of the projection apparatus, so that the auxiliary openings themselves are not printed onto the wafer. However, the auxiliary openings do enhance the contrast of the aerial image, in particular of an associated, isolated or semi-isolated opening on the wafer. The auxiliary openings may have a distance from the opening that lies above the resolution limit of the projection apparatus but that is less than the coherence length of the light used for the projection. A phase-related utilization of the optical proximity effect results, which can produce elliptical structures from square openings on the mask when the auxiliary openings are disposed in the preferential direction.

Photolithographic mask and methods for producing a structure and of exposing a wafer in a projection apparatus

A mask contains a transparent carrier material on which an opaque region is disposed as an image structure. Also disposed on the carrier material is a semitransparent dummy structure, which is spaced apart from all the image structures and differs from the image structure in terms of transparency and phase rotation. The smallest lateral extent of the dummy structure is then selected to be at least half as large as the smallest lateral extent of the image structure. The semitransparent dummy structure is formed in such a way that it is suitable for increasing the depth of focus of structures that stand individually or at least partially individually, in order thereby to improve the process window of the optical projection.

Mask for optical projection systems, and a process for its production

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Dresden, Germany

Rainer Pforr