Light weight high-stiffness stage platen
AssigneeEuv LLC
InventorPaul A. Spence
Life of this patent
Estimating the term…
Abstract
An improved light weight, stiff stage platen for photolithography is provided. The high stiffness of the stage platen is exemplified by a relatively high first resonant vibrational mode as determined, for instance, by finite element modal analysis. The stage platen can be employed to support a chuck that is designed to secure a mask or wafer. The stage platen includes a frame that has interior walls that define an interior region and that has exterior walls wherein the outer surfaces of at least two adjacent walls are reflective mirror surfaces; and a matrix of ribs within the interior region that is connected to the interior walls wherein the stage platen exhibits a first vibrational mode at a frequency of greater than about 1000 Hz.
Claims42
A stage platen, for supporting a chuck on an upper surface, the stage platen comprising:
- a frame that has interior walls that define an interior region and that has exterior walls wherein the outer surfaces of at least two adjacent exterior walls are reflective mirror surfaces wherein the frame has a rectangular interior contour with four corners and the matrix comprises (i) two main ribs each of which are attached to opposite corners of the frame and (ii) a plurality of diagonal ribs each of which is attached to adjacent interior walls of the interior surface;
- and
- a matrix of ribs within the interior region that are connected to the interior walls.
A stage platen, for supporting a chuck on an upper surface, the stage platen comprising:
- a frame that has interior walls that define an interior region and that has exterior walls wherein the outer surfaces of at least two adjacent exterior walls are reflective mirror surfaces;
- and
- a matrix of ribs within the interior region that are connected to the interior walls wherein the stage platen exhibits a first vibrational mode at a frequency of greater than about 1100 Hz.
A stage platen assembly that comprises:
- (a) a stage platen that includes:
- (i) a frame that has a rectangular interior contour with four corners and that has interior walls that define an interior region and that has exterior walls wherein the outer surfaces of at least two exterior adjacent walls are reflective mirror surfaces;
- and
- (ii) a matrix comprises within the interior region that are connected to the interior walls wherein the matrix of ribs two main ribs each of which are attached to opposite corners of the frame and (ii) a plurality of diagonal ribs each of which is attached to adjacent interior walls of the interior surface;
- (b) a chuck having an upper surface adapted to support a substrate wherein the chuck is attached to the matrix of ribs;
- and
- (c) actuators for moving the stage platen in vertical and horizontal directions wherein the actuators are attached to a lower surface of the stage platen.
A process for fabrication of a device comprising at least one element having a dimension ≦0.25 μm, such process comprising construction of a plurality of successive levels, construction of each level comprising lithographic delineation, in accordance with which a subject mask pattern is illuminated to produce a corresponding pattern image on the device being fabricated, ultimately to result in removal of or addition of material in the pattern image regions, in which illumination used in fabrication of at least one level is extreme ultra-violet radiation, characterized in that the process employs a stage platen assembly that comprises:
- (a) a stage platen that includes:
- (i) a frame that has a rectangular interior contour with four corners and that has interior walls that define an interior region and that has exterior walls wherein the outer surfaces of at least two exterior adjacent walls are reflective mirror surfaces;
- and
- (ii) a matrix of ribs within the interior region that are connected to the interior walls wherein the matrix comprises two main ribs each of which are attached to opposite corners of the frame and a plurality of diagonal ribs each of which is attached to adjacent interior walls of the interior surface;
- (b) a chuck having an upper surface adapted to support a substrate wherein the chuck is attached to the matrix of ribs;
- and
- (c) actuators for moving the stage platen in vertical and horizontal directions wherein the actuators are attached to a lower surface of the stage platen.
Dependencies are inferred from the claim text.