1. A photomask construction, comprising:
a reticle base; and
a radiation-patterning topography across the reticle base; the radiation-patterning topography comprising pillars that individually contain at least seven distinct layers, and comprising gaps between the pillars; the pillars being transmissive of actinic radiation passed through the photomask construction, each of the layers being optimized relative to a refractive index, extinction coefficient and thickness for maximum imaging contrast between radiation passing through the pillars and radiation passing through the gaps.
2. The construction of claim 1 further comprising liners along sidewalls of the pillars, the liners narrowing the gaps but not eliminating the gaps.
3. The construction of claim 1 wherein the at least seven distinct layers primarily comprise only two distinct materials.
4. The construction of claim 3 wherein said two distinct materials are silicon and molybdenum.
5. The construction of claim 4 wherein the at least seven distinct layers are at least 80 distinct layers.
6. The construction of claim 1 wherein the at least seven distinct layers comprise more than two distinct materials.
7. A photomask construction comprising:
a base comprising quartz; and
a plurality of spaced-apart features supported by the base, individual features comprising alternating first and second layers, the individual features containing a combined total of the first and second layers of at least seven, each of the layers being optimized relative to a refractive index, extinction coefficient and thickness for maximum imaging contrast between radiation passing through the pillars and radiation passing through the gaps.
8. The construction of claim 7 wherein the first layers consist of silicon and the second layers consist of molybdenum.
9. The construction of claim 7 further comprising molybdenum silicide along interfaces of the first and second layers.
10. The construction of claim 7 further comprising a liner extending along sidewalls of the features.
11. The construction of claim 10 wherein the liner comprises one or more members of the group consisting of SiO2, Si3N4, SrF2, MgF2, Al2O3, BaF2, Al, TiN, Cu, Cr and Si.
12. A photomask construction comprising:
a reticle base;
a plurality of pillars comprising stacked layers numbering q, where q is greater than or equal to three, the layers each independently comprising one or more of silicon, silicon dioxide, silicon nitride, tantalum nitride, molybdenum sulfide, MoSix, MoSixOy, MoSixOyNz, TaxHfy, TaxNy, and SixOyNz, where x, y, and z are greater than zero; and
gaps between the pillars, each of the layers being optimized relative to a refractive index (n), extinction coefficient (k value) and thickness in order to obtain maximum imaging contrast between radiation passing through the pillars and radiation passing through the gaps.
13. The construction of claim 12 wherein the number of layers in the pillars varies.
14. The construction of claim 12 further comprising a layer of material formed across the pillars and across the gaps.
15. The construction of claim 12 wherein the optimization is achieved utilizing an optimization loop for layers 1 to q comprising utilizing parameters n, k value and thickness to perform at least one iteration of the following:
vary a first parameter while holding a second and third parameters constant to ascertain an optimized value of the first parameter for chosen conditions;
vary the second parameter while holding the first and third parameters constant to ascertain an optimized value of the second parameter for the chosen conditions, the first parameter being held constant at the optimized value of the first parameter for the chosen conditions while the second parameter is varied; and
vary the third parameter while holding the first and second parameters constant at the optimized values for the first and second parameters for the chosen condition.
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 planar electric precipitator for an air stream, comprising:
planar electrode plate made of electricity-conducting material, having a plurality of electrode units arrayed thereon, each of said electrode units having at least one electrode opening with an inner periphery having at least two electrode tips;
a planar collecting plate, generally parallel to and downstream of said electrode plate and made of electricity-conducting material, having a plurality of collecting units arrayed thereon, each of said collector units having at least one air hole and at least one collector surface which is oriented transverse to a bulk air stream direction and positioned downstream of said corresponding electrode unit;
wherein direct electric voltage is applied between said electrode plate and said collecting plate, so that air passing through is exposed to high electric fields close to said electrode tips of said electrode units, ionizing suspended particles and trapping ionized particles at said collecting plate, so that an air-cleaning effect results.
2. The planar electric precipitator according to claim 1, wherein each of said collecting units has a plurality of air holes at rotationally equiangular positions adjacent to each of said collector surfaces.
3. The planar electric precipitator according to claim 1, wherein said electrode plate and said collecting plate are each a continuous sheet, with a plurality of fixing elements inserted between said electrode plate and said collecting plate, ensuring that said electrode plate and said collecting plate are oriented parallel to each other.
4. The planar electric precipitator according to claim 1, wherein each electrode unit of said plurality of electrode units comprises an electrode opening and a plurality of electrode tips.
5. The planar electric precipitator according to claim 4, wherein for each electrode unit of said plurality of electrode units, said plurality of electrode tips are bent away from said electrode opening at a defined angle.
6. The planar electric precipitator according to claim 4, wherein for each electrode unit of said plurality of electrode units, said plurality of electrode tips are oriented parallel to said electrode opening.
7. The planar electric precipitator according to claim 2, wherein said plurality of electrode units and said plurality of collecting units are centrally aligned to each other.
8. The planar electric precipitator according to claim 2, wherein each collecting unit of said plurality of collecting units comprises a collector surface, which is aligned directly downstream of said electrode opening of one electrode unit of said plurality of electrode units, wherein said collector surface causes stagnation flow downstream of said electrode opening.
9. The planar electric precipitator according to claim 8, wherein for each collecting unit of said plurality of collecting units, said collector surface is surrounded by several air holes, allowing air to pass through.
10. The planar electric precipitator according to claim 3, wherein said electrode plate and said collecting plate, with said fixing elements having been inserted, are mounted on a frame.
11. The planar electric precipitator according to claim 10, wherein said frame has a central opening, allowing air to pass through.
12. The planar electric precipitator according to claim 10, wherein said frame is covered by a cover plate to prevent accidental touching of said electrode plate.
13. The planar electric precipitator according to claim 12, wherein said cover plate has a plurality of ventilation openings, allowing air to enter said electrode plate.
14. The planar electric precipitator according to claim 13, wherein said cover plate has a decorative design for good looks.
15. The planar electric precipitator according to claim 4, wherein for each electrode unit of said plurality of electrode units, said plurality of electrode tips are bent towards said collecting plate at a defined angle.
16. The planar electric precipitator according to claim 10, wherein said frame on a side close to said collecting plate has at least one ventilator to increase air flow towards said electrode plate and said collecting plate.
17. The planar electric precipitator according to claim 16, wherein for each electrode unit of said plurality of electrode units, said plurality of electrode tips are oriented not parallel to said electrode plate, reaching closer to said collecting plate than said electrode plate does.
18. The planar electric precipitator according to claim 1, wherein said collecting plate is a single plane sheet.
19. The planar electric precipitator according to claim 10, wherein said electrode plate, said collecting plate and said frame are fastened to each other by bolts and nuts.
20. The planar electric precipitator according to claim 12, wherein said cover plate is fastened to said frame by screws and nuts.