Photoresist polymers
View Patent ↗The present invention is directed to the preparation of photoresist polymers via living free radical polymerization techniques. Sterically bulky ester monomers are utilized as the polymerization components. Use of chain transfer agents is included in polymerization processing conditions. Cleavage of polymer terminal end groups that include a heteroatom are described.
1. A polymer comprising the formula:
[A] x [B] y [C] z
wherein A, B and C are each individually one of
wherein x is between about 0 and about 200 inclusive, y is between about 1 and about 200 inclusive and z is between about 1 and about 200 inclusive, provided B≠C
wherein the polymer is prepared by a living free radical process (LFRP) in the presence of a chain transfer agent (CTA) having the formula:
wherein R 1 is any group that can be expelled as its free radical form in an addition-fragmentation reaction;
R 2 and R 3 are each independently selected from the group consisting of hydrogen, hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, and substituted heteroatom-containing hydrocarbyl, and combinations thereof, and optionally R 2 and R 3 together to form a double bond optionally substituted alkenyl moiety;
R 4 is selected from the group consisting of hydrogen, hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, and substituted heteroatom-containing hydrocarbyl, and combinations thereof; and optionally, R 4 combines with R 2 and/or R 3 to form a ring structure, with said ring having from 3 to 50 non-hydrogen atoms; and
D is either sulfur, selenium or tellurium.
2. The polymer of claim 1 , wherein x is at least 1.
3. The polymer of claim 1 , wherein the polydispersity index is less than 1.7.
4. The polymer of claim 1 , wherein the polydispersity index is between about 1.2 to about 1.4.
5. The polymer of claim 1 , wherein the M w is between about 3,000 and about 20,000.
6. The polymer of claim 1 , wherein the M w is between about 3,000 and about 10,000.
7. The polymer of any one of claims 1 - 6 , wherein A, B and C are each individually one of
and
x is at least 1.
8. The polymer of any one of claims 1 - 6 , wherein A, B and C are each individually one of
and x is at least one.
9. The polymer of claim 8 , wherein the formula is
10. The polymer of claim 9 , wherein the M w is between about 3,000 and 10,000.
11. The polymer of claim 9 , wherein the polydispersity index is about 1.3.
12. The polymer of any one of claims 1 - 6 , wherein A, B and C are each individually one of
and x is at least one.
13. The polymer of claim 12 , wherein the formula is
14. The polymer of claim 13 , wherein the M w is between about 3,000 to about 12,000.
15. The polymer of claim 13 , wherein the polydispersity index is between about 1.1 and about 1.2.
16. The polymer of any one of claims 1 - 6 , wherein A, B and C are each individually one of
and x is at least one.
17. The method of claim 16 , wherein the formula is
18. The method of claim 17 , wherein the M w of the polymer is between about 3,000 to about 12,000.
19. The method of claim 17 , wherein the polydispersity index of the polymer is between about 1.1 and about 1.2.
20. The polymer of any one of claims 1 - 6 , wherein the terminal end position includes a thiocarbonylthio moiety.
21. The polymer of any one of claims 1 - 6 , wherein the terminal end position includes a termination group having the formula
wherein R′ is CN or COOMe.