We claim:
1. A method for removing polysilane from a semiconductor substrate without stripping during manufacture of a semiconductor device, comprising:
a) coating a polysilane on a semiconductor substrate and coating a resist on said polysilane;
b) patterning said resist with exposure and development;
c) transferring the pattern from said resist to said polysilane using an etch process selective to said resist;
d) stripping said resist;
e) transferring the pattern from said polysilane to a hardmask using an etch selective to said hardmask;
f) subjecting said polysilane to thermal or plasmathermal oxidation to convert said polysilane to silica; and
g) etching the substrate and stripping off the hard mask.
2. The method of claim 1 wherein in step a) said polysilane is coated by spin coating.
3. The method of claim 1 wherein in step a) said polysilane is coated by dipping.
4. The method of claim 1 wherein in step a) said polysilane is coated by casting.
5. The method of claim 1 wherein step a) said polysilane is coated by vacuum evaporation.
6. The method of claim 1 wherein step a) said polysilane is coated by a Langmuir-Blodgett method.
7. The method of claim 2 wherein said polysilane has the formula:
(R1m R2n Xp Si)q(I)
wherein R1 and R2, may be the same or different, are substituted or unsubstituted monovalent hydrocarbon groups, X is a substituted or unsubstituted monovalent hydrocarbon group, alkoxy group or halogen atom, letters m, n and p are numbers satisfying 1mnp<2.2 and q is an integer of from 10 to 100,000;
when R1 and R2 are aliphatic or alicyclic hydrocarbon groups,
the number of carbon atoms is 1 to 12; when R1 and R2 are aromatic hydrocarbon groups, the number of carbon atoms is 6 to 14; and
X is a group as defined for R1, or an alkoxy group of 1 to 8 carbon atoms or a halogen atom.
8. The method of claim 7 wherein said polysilane is in a solvent solution containing a polysilane concentration of from about 1 to about 20% by weight.
9. The method of claim 8 wherein said solvent is an aromatic hydrocarbon.
10. The method of claim 9 wherein said aromatic hydrocarbon is selected from the group consisting of benzene, toluene and xylene.
11. The method of claim 8 wherein said solvent is an ether solvent.
12. The method of claim 11 wherein said ether solvent is selected from tetrahydrofuron or dibutyl ether.
13. The method of claim 2 wherein said thermal or plasma thermal oxidation proceeds at a temperature range of from about 200 C. to about 1000 C.
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. A mirror support structure comprising:
a first mirror and a second mirror disposed a predetermined distance apart from each other in a face-to-face relation;
a first mirror support member and a second mirror support member supporting said first mirror and said second mirror, respectively;
a plurality of main rods connecting said first mirror support member and said second mirror support member with each other;
a plurality of auxiliary rods joined at one ends thereof to said first mirror support member or said second mirror support member and at the other ends thereof to a single connection point;
a plurality of support legs for indirectly supporting said first and second mirrors at a total of three points including two points on said first mirror support member and said single connection point at which said auxiliary rods are joined together; and
a base on which said support legs are fixedly mounted; wherein said support legs are composed of follower members capable of following an expansion or contraction of said base.
2. The mirror support structure as claimed in claim 1, wherein said first mirror support member and said second mirror support member are each composed of a triangular-shaped panel, and said main rods and said auxiliary rods comprise three pairs of main and auxiliary rods joined together in each pair to form a continuous and integral rectilinear configuration, said three pairs of continuously and integrally joined main and auxiliary rods serving to connect three apexes of said first triangular-shaped mirror support member with three corresponding apexes of said second triangular-shaped mirror support member, respectively, to cooperate with three sides of said first triangular-shaped mirror support member and three sides of said second triangular-shaped mirror support member to form a trussed structure.
3. The mirror support structure as claimed in claim 2, wherein said main rods comprise additional main rods connecting three apexes of said first triangular-shaped mirror support member with three different apexes of said second triangular-shaped mirror support member in combinations different from those in which the three apexes of said first triangular-shaped mirror support member and the three corresponding apexes of said second triangular-shaped mirror support member are connected with each other by means of said three pairs of continuous and integrally joined main and auxiliary rods.
4. The mirror support structure as claimed in claim 1, wherein said first mirror support member and said second mirror support member are each composed of a triangular-shaped panel, and said main rods comprise six main rods connecting three apexes of said first mirror support member and three apexes of said second mirror support member, respectively, and said auxiliary rods comprise three auxiliary rods joined to three apexes of said second mirror support member, respectively, said six main rods and said three auxiliary rods cooperating with three sides of said first triangular-shaped mirror support member and three sides of said second triangular-shaped mirror support member to form a trussed structure.
5. The mirror support structure as claimed in claim 1, wherein said first mirror support member and said second mirror support member are each composed of a triangular-shaped panel, and said first triangular-shaped mirror support member and said second triangular-shaped mirror support member are arranged such that they have one side disposed in parallel with a surface of said base, and said main rods comprise six main rods connecting three apexes of said first triangular-shaped mirror support member and three apexes of said second triangular-shaped mirror support member with each other, and said auxiliary rods comprise three auxiliary rods joined to the three apexes of said first triangular-shaped mirror support member, respectively, said six main rods and said three auxiliary rods cooperating with three sides of said first triangular-shaped mirror support member and three sides of said second triangular-shaped mirror support member to form a trussed structure.
6. The mirror support structure as claimed in claim 1, wherein said first mirror support member and said second mirror support member are each composed of a triangular-shaped panel, and said first triangular-shaped mirror support member and said second triangular-shaped mirror support member are arranged such that they have each side disposed in antiparallel with a surface of said base, and said main rods comprise six main rods connecting three apexes of said first triangular-shaped mirror support member and three apexes of said second triangular-shaped mirror support member with each other, and said auxiliary rods comprise three auxiliary rods joined to three apexes of said first triangular-shaped mirror support member, respectively, said six main rods and said three auxiliary rods cooperating with three sides of said first triangular-shaped mirror support member and three sides of said second triangular-shaped mirror support member to form a trussed structure.
7. The mirror support structure as claimed in claim 1, wherein said follower members are each composed of a plate spring.