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lgadwah
http://domino.research.ibm.com/comm/research_projects.nsf/pages/selfassembly.nxta ...
iniewski
Can direct sub-assembly find application in other areas of manufacturing beyond ...
Momentum builds for directed self-assembly
Dylan McGrath
3/2/2011 4:24 PM EST
SANTA CLARA, Calif.—Directed self-assembly (DSA)—a technology based on a concept that was virtually unknown outside of research labs a few years ago—has emerged as a legitimate contender for use in future semiconductor manufacturing.
"Directed self-assembly cannot be ignored," said Christopher Bencher, a member of the technical staff at Applied Materials Inc., at the SPIE Advanced Lithography conference here Tuesday (March 1). Bencher further suggested that DSA should be moved from the list of emerging lithography technologies to the "current" technologies list.
At SPIE, Bencher presented data on self-assembly patterning for cells with a half-pitch of less than 15-nm that was collected through a joint project with IBM Research. Bencher noted that while lithographers have been enthusiastic about DSA, the biggest concern has been defect density. Bencher said his project demonstrated the use of DSA to build 12-nm line/space structures across an entire 300-mm wafer with a very low rate of less than 1 percent of "dislocation" defects.
Hundreds of particle defects were also measured during the project, but, according to Bencher, particle defects introduced through the use of DSA are no different than particle defects encountered during the use of any new process technology material and will be reduced through better filtration in the fab. Bencher's project was concerned mainly with dislocation defects because, he said, this is a new type of defect inherent to DSA.
"This clearly puts us on a trajectory to make DSA feasible, with fairly good defect control," Bencher said.
In DSA, a block copolymer or polymer blend is deposited on a substrate, usually by spin coating, and subjected to an annealing process that "directs" it to form ordered structures. Researchers say DSA is compatible with conventional 193-nm lithography equipment and would eliminate the need for dual exposure steps.
DSA first landed on the International Technology Roadmap for Semiconductors (ITRS) as a potential solution for leading-edge, critical layer lithography in 2007 and remained part of 2009 ITRS. The technology is also considered complementary to next-generation lithography candidates such as extreme ultraviolet (EUV) lithography and nano-imprint lithography.
But even the most enthusiastic supporters of DSA acknowledge that the technology is years away from being used in CMOS production, even in a best case scenario. Defect density is only one of a number of technical hurdles DSA must overcome to be viable in volume production.
Yoshi Hishiro, director or R&D at materials supplier JSR Micro Inc., estimated that DSA was at least two to three years away from being used in niche CMOS production.
Attendees at SPIE are nervous about the prospects for EUV, long considered the front runner to replace optical lithography. Intel Corp. hopes to put EUV into production at the 10-nm node, but this week its lithography director said EUV is running late for 10-nm design rule definition. Development of power sources for EUV lithography tools remains behind schedule, and several SPIE attendees expressed concern that EUV was still dealing with "basic physics" issues.
Next: Possible niche role
"Directed self-assembly cannot be ignored," said Christopher Bencher, a member of the technical staff at Applied Materials Inc., at the SPIE Advanced Lithography conference here Tuesday (March 1). Bencher further suggested that DSA should be moved from the list of emerging lithography technologies to the "current" technologies list.
At SPIE, Bencher presented data on self-assembly patterning for cells with a half-pitch of less than 15-nm that was collected through a joint project with IBM Research. Bencher noted that while lithographers have been enthusiastic about DSA, the biggest concern has been defect density. Bencher said his project demonstrated the use of DSA to build 12-nm line/space structures across an entire 300-mm wafer with a very low rate of less than 1 percent of "dislocation" defects.
Hundreds of particle defects were also measured during the project, but, according to Bencher, particle defects introduced through the use of DSA are no different than particle defects encountered during the use of any new process technology material and will be reduced through better filtration in the fab. Bencher's project was concerned mainly with dislocation defects because, he said, this is a new type of defect inherent to DSA.
"This clearly puts us on a trajectory to make DSA feasible, with fairly good defect control," Bencher said.
In DSA, a block copolymer or polymer blend is deposited on a substrate, usually by spin coating, and subjected to an annealing process that "directs" it to form ordered structures. Researchers say DSA is compatible with conventional 193-nm lithography equipment and would eliminate the need for dual exposure steps.
DSA first landed on the International Technology Roadmap for Semiconductors (ITRS) as a potential solution for leading-edge, critical layer lithography in 2007 and remained part of 2009 ITRS. The technology is also considered complementary to next-generation lithography candidates such as extreme ultraviolet (EUV) lithography and nano-imprint lithography.
But even the most enthusiastic supporters of DSA acknowledge that the technology is years away from being used in CMOS production, even in a best case scenario. Defect density is only one of a number of technical hurdles DSA must overcome to be viable in volume production.
Yoshi Hishiro, director or R&D at materials supplier JSR Micro Inc., estimated that DSA was at least two to three years away from being used in niche CMOS production.
Attendees at SPIE are nervous about the prospects for EUV, long considered the front runner to replace optical lithography. Intel Corp. hopes to put EUV into production at the 10-nm node, but this week its lithography director said EUV is running late for 10-nm design rule definition. Development of power sources for EUV lithography tools remains behind schedule, and several SPIE attendees expressed concern that EUV was still dealing with "basic physics" issues.
Next: Possible niche role
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Les_Slater
3/2/2011 8:03 PM EST
The article talks about the potential of this technology and at what development stage it may be at but doesn’t explain what it is. It was the title of the article that brought me to read it. The implications are quite attractive.
My first introduction to such concepts was at an MIT talk I attended in the late 80’s by K. Eric Wexler. What this present article is referring to does not seem to be related to his ‘universal assemblers’ though. That was a relief because the mechanism he suggested, engineering proteins for specific mechanical assembly tasks seems quite remote still.
So, on this new ‘directed self-assembly’, the question arises, what is the mechanism of the direction?
Looking around the web a bit I see there is talk of lithographic patterning and random deposition where capillary, electrostatic and van der Waals forces focus or sharpen the random deposition to conform to the lithographic pattern. Is this what we’re talking about here? Sounds exciting.
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Les_Slater
3/2/2011 8:05 PM EST
The article talks about the potential of this technology and at what development stage it may be at but doesn’t explain what it is. It was the title of the article that brought me to read it. The implications are quite attractive.
My first introduction to such concepts was at an MIT talk I attended in the late 80’s by K. Eric Wexler. What this present article is referring to does not seem to be related to his ‘universal assemblers’ though. That was a relief because the mechanism he suggested, engineering proteins for specific mechanical assembly tasks seems quite remote still.
So, on this new ‘directed self-assembly’, the question arises, what is the mechanism of the direction?
Looking around the web a bit I see there is talk of lithographic patterning and random deposition where capillary, electrostatic and van der Waals forces focus or sharpen the random deposition to conform to the lithographic pattern. Is this what we’re talking about here? Sounds exciting.
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dylan.mcgrath
3/3/2011 1:01 PM EST
@les_slater- paragraph 6 of the above article is my best attempt at explaining what I understand DSA to be in the simplest possible terms. I realize it probably falls short. I solicited this quote from Christopher Bencher of Applied Materials to describe what DSA is. I hope it helps:
"Self assembly is a method of patterning using polymer phase-separation to generate features, typically less than 20nm, instead of relying solely on the classic mask projection into photo-resist. It has now established the first 300mm wafer defect density data point for directed self-assembly, and when plotted on historical defect density reduction roadmaps appears to be quite promising; the initial value is comparable to the immersion defect densities in its early years of commercialization. This result merits continued research and development for establishing directed self-assembly as a viable patterning technique for semiconductor manufacturing." -- Christopher Bencher, Applied Materials
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Les_Slater
3/2/2011 8:17 PM EST
K. Eric Wexler is of course, K. Eric Drexler.
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double-o-nothing
3/3/2011 10:08 AM EST
The number of self-assembled lines is too sensitive to the boundary size. A line could disappear if the boundary is a tad narrow.
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selinz
3/3/2011 11:31 PM EST
This sounds similar to the Langmuir blodgett films that IBM was working on in 1983... Cool stuff but it's been around quite a while.. Nice application though.
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iniewski
3/4/2011 11:23 AM EST
Can direct sub-assembly find application in other areas of manufacturing beyond lithography? Kris
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lgadwah
3/4/2011 2:39 PM EST
http://domino.research.ibm.com/comm/research_projects.nsf/pages/selfassembly.nxtalFLASH.html
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