I claim:
1. A reticle used for making a semiconductor device in a photolithography process, comprising:
a device exposure region having sides and a device pattern within an area defined by the sides;
an opaque chrome region disposed adjacent to the device region; and
a kerf region surrounded by the opaque chrome region, the kerf region being offset from the sides of the device exposure region by the opaque chrome region.
2. The reticle of claim 1, wherein the device exposure region has first, second, third, and fourth sides.
3. The reticle of claim 2, wherein the device exposure region has a rectangular shape.
4. The reticle of claim 2, wherein the reticle includes first, second, third, and fourth kerf regions surrounded by the opaque chrome region, and the first, second, third, and fourth kerf regions are located offset from the first, second, third, and fourth sides of the device exposure regions correspondingly.
5. The reticle of claim 2, wherein the reticle includes corner kerf regions surrounded by the opaque chrome region, and each of the corner kerf regions are located diagonally offset from each corner defined by the first, second, third, and fourth sides of the device exposure region.
6. The reticle of claim 1, wherein the opaque chrome region surrounds the device exposure region.
7. The reticle of claim 1, wherein the kerf region has a substantially same width as a width of the opaque chrome region located between the device exposure region and the kerf region.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A respirator comprising:
a face mask comprising an opening formed therethrough; and
a unidirectional valve comprising a valve flap located over the opening of the face mask, wherein the valve is movable from a first position in which the opening is closed by the valve flap to a second position in which a portion of the valve flap is spaced from the opening such that fluids can pass through the opening, wherein the valve flap comprises a nonuniform thickness, wherein the valve flap comprises a first end and a second end opposite the first end, wherein the first end is attached to the face mask and wherein the second end is not attached to the face mask.
2. A respirator according to claim 1, wherein the valve flap comprises a first end and a second end opposite the first end, wherein the first end is attached to the face mask and wherein the second end is not attached to the face mask, and further wherein the valve flap is ticker at the first end than at the second end.
3. A respirator according to claim 1, wherein the valve flap comprises a first end and a second end opposite the first end, wherein the first end is attached to the face mask and wherein the second end is not attached to the face mask, and wherein the valve flap is thicker at the first end than at the second end, and further wherein the nonuniform thickness of the valve flap tapers gradually from the first end to the second end.
4. A respirator according to claim 1, wherein the valve flap comprises a first end and a second end opposite the first end, wherein the first end is attached to the face mask and wherein the second end is not attached to the face mask, and wherein the valve flap is thicker at the first end than at the second end, and further wherein the nonuniform thickness of the valve flap tapers gradually from the first end to the second end.
5. A respirator according to claim 1, wherein the valve flap comprises a first end and a second end opposite the first end, wherein the first end is attached to the face mask and wherein the second end is not attached to the face mask, and further wherein the valve flap is thicker at the second end than at the first end.
6. A respirator according to claim 1, wherein the valve flap comprises a first end and a second end opposite the first end, wherein the first end is attached to the face mask and wherein the second end is not attached to the face mask, and wherein the valve flap is thicker at the second end than at the first end, and further wherein the nonuniform thickness of the valve flap tapers gradually from the second end to the first end.
7. A respirator according to claim 1, wherein the face mask comprises a half facepiece respirator.
8. A respirator according to claim 1, wherein the face mask comprises a mask body made of filtering material that is permeable to air, and wherein the opening is formed in the mask body.
9. A respirator according to claim 1, wherein the valve flap comprises a curvature, and wherein the curvature of the valve flap is at least partially flattened when the valve flap is in the first position in which the opening is closed by the valve flap.
10. A respirator comprising:
a face mask comprising a mask body made of filtering material that is permeable to air; an opening formed through the mask body; and
a unidirectional valve comprising a valve flap located over the opening formed through the mask body, wherein the valve is movable from a first position in which the opening is closed by the valve flap to a second position in which a portion of the valve flap is spaced from the opening such that fluids can pass through the opening, wherein the valve flap comprises a nonuniform thickness, and wherein the valve flap comprises a first end and a second end opposite the first end, wherein the first end is attached to the face mask and wherein the second end is not attached to the face mask.
11. A respirator according to claim 10, wherein the valve flap comprises a first end and a second end opposite the first end, wherein the first end is attached to the face mask and wherein the second end is not attached to the face mask, and further wherein the valve flap is thicker at the first end than at the second end.
12. A respirator according to claim 10, wherein the valve flap comprises a first end and a second end opposite the first end, wherein the first end is attached to the face mask and wherein the second end is not attached to the face mask, and wherein the valve flap is thicker at the first end than at the second end, and further wherein the nonuniform thickness of the valve flap tapers gradually from the first end to the second end.
13. A respirator according to claim 10, wherein the valve flap comprises a first end and a second end opposite the first end, wherein the first end is attached to the face mask and wherein the second end is not attached to the face mask, and wherein the valve flap is thicker at the first end than at the second end, and further wherein the nonuniform thickness of the valve flap tapers gradually from the first end to the second end.
14. A respirator according to claim 10, wherein the valve flap comprises a first end and a second end opposite the first end, wherein the first end is attached to the face mask and wherein the second end is not attached to the face mask, and further wherein the valve flap is thicker at the second end than at the first end.
15. A respirator according to claim 10, wherein the valve flap comprises a first end and a second end opposite the first end, wherein the first end is attached to the face mask and wherein the second end is not attached to the face mask, and wherein the valve flap is thicker at the second end than at the first end, and further wherein the nonuniform thickness of the valve flap tapers gradually from the second end to the first end.
16. A respirator according to claim 10, wherein the valve flap comprises a curvature, and wherein the curvature of the valve flap is at least partially flattened when the valve flap is in the first position in which the opening is closed by the valve flap.
17. A respirator comprising:
a face mask comprising a mask body made of filtering material tat is permeable to air; an opening formed through the mask body; and
a unidirectional valve comprising a valve flap located over the opening formed through the mask body, wherein the valve is movable from a first position in which the opening is closed by the valve flap to a second position in which a portion of the valve flap is spaced from the opening such tat fluids can pass through the opening, wherein the valve flap comprises a first end and a second end opposite the first end, wherein the first end is attached to the face mask and wherein the second end is not attached to the face mask, and further wherein the valve flap is thicker at the first end than at the second end.
18. A respirator according to claim 17, wherein the thickness of the valve flap tapers gradually from the first end to the second end.
19. A respirator according to claim 17, wherein the valve flap comprises a curvature, and wherein the curvature of the valve flap is at least partially flattened when the valve flap is in the first position in which the opening is closed by the valve flap.