1. A method for constructing an assembly comprising at least two base wafers, said method comprising:
a) providing a first base wafer having front and back sides, wherein the front side comprises integrated circuits disposed thereon and wherein the base wafer comprises at least one conductive via comprising conductive metal and extending from the front of the base wafer at least partially through the base wafer;
b) affixing the front side of the base wafer having integrated circuits thereon to a carrier;
c) contacting the back side of the base wafer with a polishing pad and a first CMP slurry, said first CMP slurry comprising:
1) a liquid carrier;
2) between 0.1% and 20% by weight of an oxidizer selected from the group consisting of periodic acid or salt thereof, perchloric acid or salt thereof, a persulfate salt or acid thereof, a permanganate salt or acid thereof, ozone, silver oxide, and elemental fluorine;
3) an abrasive; and
4) at least one metal chelating agent, and
d) polishing the backside of the base wafer until at least one conductive via is exposed, wherein the first base wafer is polished using the first CMP slurry at a rate of at least 5,000 angstroms per minute at 7 psi or less of down-force.
2. The method of claim 1 wherein the first base wafer is a silicon wafer.
3. The method of claim 1 wherein the conductive metal is selected from the group consisting of copper and tungsten.
4. The method of claim 1 wherein the oxidizer is selected from the group consisting of periodic acid or salt thereof, perchloric acid or salt thereof, and a persulfate salt or acid thereof.
5. The method of claim 1 wherein the oxidizer is periodic acid.
6. The method of claim 1 wherein the metal chelating agent comprises an aminocarboxylic acid having the structure H2N\u2014R\u2014COOH, where R is a straight or branched alkyl group having between 1 and 6 carbon atoms.
7. The method of claim 6 wherein the metal chelating agent further comprises a hydroxy-carboxylic acid.
8. The method of claim 6 wherein the metal chelating agent is glycine.
9. The method of claim 8 wherein the metal chelating agent is glycine in combination with citric acid.
10. The method of claim 1 wherein the first base wafer is polished using the slurry at a rate of at least 10,000 angstroms per minute at 7 psi or less of down-force.
11. The method of claim 1 wherein the slurry further comprises between 0.0005% by weight and 0.1% by weight of a corrosion inhibitor.
12. The method of claim 1 wherein the slurry comprises between 0.01% and 5% by weight of a citrate salt.
13. The method of claim 1 wherein the slurry comprises between 0.01% and 5% by weight of periodic acid, between 0.3% and 1.5% by weight of ammonium hydroxide, and wherein the pH is between about 8 and about 14.
14. The method of claim 1 wherein the liquid carrier comprises water.
15. The method of claim 11 wherein the corrosion inhibitor is a phenolic compound.
16. The method of claim 15 wherein the phenolic compound in the first CMP slurry is catechol present at a level between 0.001% and 5% by weight.
17. The method of claim 1 wherein the first base wafer: conductive metal selectivity ranges from about 0.5 to about 2.0.
18. The method of claim 1 wherein the base wafer is polished using the first CMP slurry at a rate of at least 7,500 angstroms per minute at 7 psi or less of down-force.
19. The method of claim 1 wherein the pH of the first CMP slurry is basic.
20. The method of claim 1 wherein the backside of the base wafer is not subjected to a grinding step before chemically mechanically polishing the backside of the base wafer.
21. The method of claim 1 wherein the backside of the base wafer is subjected to a grinding step before chemically mechanically polishing the backside of the base wafer.
22. The method of claim 1, further comprising the step of CMP of the backside of the base wafer with a pre-treatment slurry prior to polishing the backside of the base wafer with the first CMP slurry, wherein said pre-treatment slurry polishes the base wafer at a rate of at least 5000 angstroms per minute at a down force of 7 psi.
23. The method of claim 1, wherein the at least one conductive via comprising conductive metal and extending from the front of the base wafer further comprises a barrier material adapted to prevent conductive metal from migrating through silicon, said method further comprising the step of polishing the backside of the base wafer with a second CMP slurry after polishing the backside of the base wafer with the first CMP slurry, wherein said second CMP slurry has a conductive metal to barrier material selectivity of between 0.6 and 1.5.
24. The method of claim 1, further comprising electrically connecting a second base wafer comprising at least one exposed via to the at least one conductive via on the backside of the first base wafer.
25. The method of claim 1, further comprising forming circuits on the backside of the first base wafer after polishing the first base wafer, at least a portion of said circuits being electrically connected to the at least one exposed conductive via on the backside of the first base wafer.
26. A method for constructing an assembly comprising two wafers, said method comprising:
a) providing a silicon base wafer having front and back sides, wherein the front side comprises integrated circuits disposed thereon and wherein the silicon base wafer comprises at least one conductive via comprising copper and extending from a front side of the silicon base wafer at least partially through the silicon base wafer;
b) affixing the front side of the silicon base wafer to a carrier; and
c) contacting the back side of the silicon base wafer with a polishing pad and a first CMP slurry, said first CMP slurry comprising:
1) water;
2) between 0.05% and 10% by weight of periodic acid;
3) an abrasive; and
4) at least one of an organic acid or an amino-carboxylic acid, and
d) polishing the backside of the wafer until at least one conductive via is exposed, wherein the first CMP slurry polishes silicon at a rate of at least 10,000 angstroms per minute at 7 psi or less of down-force.
27. The method of claim 26 wherein the backside of the silicon base wafer is not subjected to a grinding step before chemically mechanically polishing the backside of the silicon wafer.
28. The method of claim 26 wherein the first CMP slurry comprises citric acid and glycine.
29. The method of claim 26 wherein the Si: Cu selectivity ranges from about 0.5 to about 1.5.
30. The method of claim 26 further comprising electrically connecting a second silicon wafer comprising at least one exposed via to the at least one conductive via on the backside of the first base wafer.
31. The method of claim 26 wherein the first CMP slurry has a pH of about 10.5 to about 11.5.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. An optical apparatus, comprising:
a light source,
a reflecting and condensing mirror for reflecting and condensing a light beam from the light source, guiding the light beam to substantially the same direction, and emitting the light beam from a light emitting part,
a first multi-lens array in which a plurality of lens are arranged, and which divides an incident light into a plurality of images, and lays out the light spots of the divided images at predetermined locations, and
a second multi-lens array in which a plurality of lens corresponding to the plurality of light spots condensed by the first multi-lens array are arranged and which is arranged in the proximity of the focal distance of the first multi-lens array, wherein
the first multi-lens array is arranged integrally at the light emitting part of the reflecting and condensing mirror so that the light reflected and condensed by the reflecting and condensing mirror is incident as said incident light.
2. An optical apparatus, comprising:
a light source,
a reflecting and condensing mirror for reflecting and condensing a light beam from the light source, guiding the light beam to substantially the same direction, and emitting the light beam from a light emitting part,
a first multi-lens array in which a plurality of lens are arranged, and which divides an incident light into a plurality of images, and lays out the light spots of the divided images at predetermined locations, and
a second multi-lens array in which a plurality of lens corresponding to the plurality of light spots condensed by the first multi-lens array are arranged and which is arranged in the proximity of the focal distance of the first multi-lens array, wherein
the first multi-lens array is arranged away from the light emitting part at the side where the light source is arranged away so that the light reflected and condensed by the reflecting and condensing mirror is incident as said incident light.
3. An optical apparatus as set forth in claim 2, wherein an aperture is formed in approximately the center portion of said first multi-lens array, and said light source is inserted into the aperture.
4. An optical apparatus as set forth in claim 2, wherein a transparent plate passing the light emitted from said first multi-lens array is arranged at the light emitting part of said reflecting and condensing mirror.
5. An optical apparatus as set forth in claim 3, wherein a transparent plate passing the light emitted from said first multi-lens array is arranged at the light emitting part of said reflecting and condensing mirror.
6. An optical apparatus as set forth in claim 2, wherein said second multi-lens array is arranged integrally at the light emitting part of said reflecting and condensing mirror.
7. An optical apparatus as set forth in claim 3, wherein said second multi-lens array is arranged integrally at the light emitting part of said reflecting and condensing mirror.
8. A projection type display apparatus comprising a modulating means for modulating and emitting a light emitted from an optical apparatus based on image information and a projection optical system for projecting the light emitted from the modulating means on a screen,
the optical apparatus comprising at least
a light source,
a reflecting and condensing mirror for reflecting and condensing a light beam from the light source, guiding the light beam to substantially the same direction, and emitting the light beam from a light emitting part,
a first multi-lens array in which a plurality of lens are arranged, and which divides an incident light into a plurality of images, and lays out the light spots of the divided images at predetermined locations, and
a second multi-lens array in which a plurality of lens corresponding to the plurality of light spots condensed by the first multi-lens array are arranged and which is arranged in the proximity of the focal distance of the first multi-lens array, wherein
the first multi-lens array is arranged integrally at the light emitting part of the reflecting and condensing mirror so that the light reflected and condensed by the reflecting and condensing mirror is incident as said incident light.
9. A projection type display apparatus comprising a modulating means for modulating and emitting a light emitted from an optical apparatus based on image information and a projection optical system for projecting the light emitted from the modulating means on a screen,
the optical apparatus comprising at least
a light source,
a reflecting and condensing mirror for reflecting and condensing a light beam from the light source, guiding the light beam to substantially the same direction, and emitting the light beam from a light emitting part,
a first multi-lens array in which a plurality of lens are arranged, and which divides an incident light into a plurality of images, and lays out the light spots of the divided images at predetermined locations, and
a second multi-lens array in which a plurality of lens corresponding to the plurality of light spots condensed by the first multi-lens array are arranged and which is arranged in the proximity of the focal distance of the first multi-lens array, wherein
the first multi-lens array is arranged away from the light emitting part at the side where the light source is arranged away so that the light reflected and condensed by the reflecting and condensing mirror is incident as said incident light.
10. A projection type display apparatus as set forth in claim 9, wherein an aperture is formed in approximately the center portion of said first multi-lens array, and said light source is inserted into the aperture.
11. A projection type display apparatus as set forth in claim 9, wherein a transparent plate passing the light emitted from said first multi-lens array is arranged at the light emitting part of said reflecting and condensing mirror.
12. A projection type display apparatus as set forth in claim 10, wherein a transparent plate passing the light emitted from said first multi-lens array is arranged at the light emitting part of said reflecting and condensing mirror.
13. A projection type display apparatus as set forth in claim 9, wherein said second multi-lens array is arranged integrally at the light emitting part of said reflecting and condensing mirror.
14. A projection type display apparatus as set forth in claim 10, wherein said second multi-lens array is arranged integrally at the light emitting part of said reflecting and condensing mirror.