i:\litho\013\Roadmap info\ITRS 07-11 3 Major Lithography Changes from 1999 ITRS Technology Node Timing accelerated 1-2 years –130nm in 2001 –100nm in 2003 90nm in 2004 MPU half-pitch accelerated one additional year.... now lags DRAM half-pitch by only one year MPU gate length (in resist) set at 70% of DRAM half-pitch …. more aggressive than ORTC MPU physical gate length (post-etch) leads MPU gate length (in resist) by one year New DRAM chip sizes allow smaller minimum field size and 5X option for advanced optical tools MEF drives much tighter optical mask requirements Changes supported by 3 of 5 regions
i:\litho\013\Roadmap info\ITRS 07-11 5 Key Concerns for 2000 ITRS Update 1) Review of technology node timing 2) SOC definition 3) ROI study (model) 4) SOC and MPU chip sizes 5) Technical issues - Scanner reduction ratio - Mask (MEF) - Defect 6) New devices - requirements, etc.
i:\litho\013\Roadmap info\ITRS 07-11 6 2000 ITRS Technology Node Timing Roadmap timing continues to be one of the major concerns for Lithography ITWG Discussed extensively by all 5 regions at April and July ITWG meetings. Industry surveys conducted in Japan and USA. Consensus was not reached at July ITRS workshop Three proposals made since July meeting: #1 – IRC ORTC Revision 1 ke, 7/28/00 #2 – USA Lithography TWG, 9/1/00 #3 – Japan Lithography TWG, 9/28/00 Two regions voted for proposal #2, one for proposal #3, and two abstained Lithography Requirements are based on proposal #2
i:\litho\013\Roadmap info\ITRS 07-11 7 2000 ITRS Chip & Field Size High performance (HP) MPU drove minimum field size in 1999 Roadmap (>800mm 2 at 50nm node) Chip Size Study Group (CSSG) reviewed models and current chips in this market segment –Recommended changing model to cut on-chip cache in half (1M in 1999 and doubling every 2 years) HP MPU chip size at 35nm node is now ~ 600mm 2 –MPU designs can be very flexible, will be driven by economics, and should not be used to drive scanner field sizes CSSG also recommended that scanner field sizes should be driven by DRAM... 2 production chips/field
i:\litho\013\Roadmap info\ITRS 07-11 8 2000 ITRS Chip & Field Size FEP ITWG studied issues with DRAM model, a factor is too aggressive –Analyzed tradeoffs of chip size growth rates, density increase rates, a factor, and scanner field sizes (800mm 2 @ 4X, and 572mm 2 @ 5X on 6-inch glass) –Final results show that 2 production chips can be contained in 572mm 2 field size IRC agreed with FEP ITWG and CSSG recommendations and included in ORTC Lithography TWG recommends staying at 6-inch glass for now and studying productivity benefits of 7-inch glass in the future
i:\litho\013\Roadmap info\ITRS 07-11 9 Scanner Reduction Ratio (SRR) ITWG recommends following issues be addressed at May 8, 2000 SRR Workshop organized by ISMT 1) What is the timing? Node, year, wavelength? 2) Comprehensive cost analysis - Impact of throughput reduction - Impact on mask industry; what real benefit do they get? - Does it help accelerate the Roadmap? 3) Complications of 4X, 5X/6X on leading edge mask making? 4) Do all scanner suppliers have to agree? What if they dont? 5) Impact on NGL? Must they follow? Especially EPL?
i:\litho\013\Roadmap info\ITRS 07-11 10 Scanner Reduction Ratio (SRR) Workshop May 8, 2000 The 62 attendees represented a broad cross-section of the industry Voting restricted to one response per company represented –One exception is allowed; captive mask manufacturers are asked to vote separately from their respective wafer lines Chip Manufacturers Mask Manufacturers
i:\litho\013\Roadmap info\ITRS 07-11 11 Mask Availability by Magnification Participants believed that the 70nm node mask availability could be improved by 2+ years if magnification increased above 4X
i:\litho\013\Roadmap info\ITRS 07-11 12 Optical Reticle Size Choice - 157nm Stay at 6 –Minimal support for larger reticles –More support for 7 than 9 Introduce 157nm with 5X Secondary choice mixed –6X has more votes than 4X 100nm Node - 157nm 0 5 10 15 20 25 30 4X 6"5X 6"6X 6"5X 7"6X 7"5X 9"6X 9"No 2nd Choice 70nm Node - 157nm 0 5 10 15 20 25 30 4X 6"5X 6"6X 6"5X 7"6X 7"5X 9"6X 9"No 2nd Choice
i:\litho\013\Roadmap info\ITRS 07-11 13 Recommendations of Tool Suppliers ( 157nm Technology, Updated 11/9/00) PrimarySecondary ASML 5X 6 --- Canon 5X 6 --- Nikon 4X 6 (5X 6) * SVGL 4X 6 --- * However: If reticle accuracy can not be satisfied in the future, Nikon accepts changing to 5X for 157nm under the conditions of…. Accepting lower throughput. Firmly standardizing optical reduction ratio. Accepting difficulties in mix & match between 4X & 5X.
i:\litho\013\Roadmap info\ITRS 07-11 14 Does NGL need to follow the magnification ratio of the optical tools?
i:\litho\013\Roadmap info\ITRS 07-11 15 SRR Workshop (5/8/00) Summary The majority choice for 157nm & 70nm node: –Mask magnification 5X –Slit height 22mm –Substrate 6-inch Recommend adding 5X as an option at 100nm & 70nm nodes for optical tools
i:\litho\013\Roadmap info\ITRS 07-11 16 Mask Error Factor (MEF) is the relation between changes in the pattern found on the mask and the corresponding pattern on the wafer: where M is the scanner reduction ratio Ideally MEF = 1.0. In practice, process variables can significantly increase the MEF as the image fidelity of the scanner deteriorates. Proposals organized through ISMT Optical Extensions & MASC groups in June meetings Mask Error Factor (MEF) and Specifications CD wafer (CD reticle) / M MEF =
i:\litho\013\Roadmap info\ITRS 07-11 17 Mask Error Factor (MEF) and Specifications ISMT contracted with IMEC to study MEF (modeling vs. experimental) Results show MEF increases very rapidly at duty ratio below 1:1.5; alternating PSM technology does NOT solve this issue Mask specifications for dense lines must be much tighter (The 1999 relaxation was shown to be unwarranted) Recommend same CD uniformity specification for alternating PSM as for binary mask; requires more study in 2001
MEF As A Function of Pitch for 100nm Lines 18
i:\litho\013\Roadmap info\ITRS 07-11 19 Lithography Requirements Exposure Tools - Table 39 –Continuous improvements in 248nm tools and processes have demonstrated solutions for DRAM and MPU down to 150nm half pitch, including CD control of 10nm –MFS for development has been demonstrated down to 70nm with 193nm + PSM –CD control solutions are being pursued down to 6nm by engineering analysis of error sources (mask, process, tool) Resists - Table 40 –Resist thickness solutions now exist down to 0.33 - 0.44 um –PEB solutions exist at 3nm / º C with 248nm resists –Resist sensitivity solutions exist for all resists except 157nm; solutions are being pursued at MIT/LL and suppliers for 157nm at 5-10 mJ/cm 2 Masks - Table 41 –Based on development of 50KeV e-beam writers, solutions now exist for mask minimum image size and OPC feature size to 200nm, image placement to 27nm, CD uniformity to 15nm, and linearity to 20nm –CD uniformity for dense lines with alternating PSM must be much tighter due to better understanding of MEF
i:\litho\013\Roadmap info\ITRS 07-11 20 Lithography Requirements - Overview Solution Exists Solution Being Pursued No Known Solution Proposed 2000 ITRS Update - 10/14/00 Work-in-Progress - Not for Publication
Lithography Exposure Tool Potential Solutions 21 Proposed 2000 ITRS Update - 10/14/00 - Work-in-Progress - Not for Publication Research Required Development UnderwayQualification/Pre-Production This legend indicates the time during which research, development, and qualification/pre-production should be taking place for the technology solution. First Year of IC Production 2001200419992010 2013 2007 248nm 248nm + PSM 193nm 193nm + PSM 157nm EPL XRL IPL Narrow Options 157nm + PSM EPL EUV IPL XRL EBDW Narrow Options EUV EPL IPL EBDW Note: Production level exposure tools should be available one year before first IC shipment. Technology Options at Technology Nodes (DRAM Half Pitch, nm) 180 130 90 65 45 33 DRAM Half Pitch (Dense Lines) Narrow Options Narrow Options EUV EPL IPL EBDW INNOVATIVE TECHNOLOGY
i:\litho\013\Roadmap info\ITRS 07-11 22 Key Challenges for Lithography in ITRS 2000 Update Impact of the technology node acceleration on lithography exposure technology and mask making capability. Gate CD control and overlay improvements. Ever tightening mask requirements, especially CD uniformity and image placement. Return on investment (ROI) for lithography suppliers, especially for single node solutions below 90nm.
i:\litho\013\Roadmap info\ITRS 07-11 24 Cost of Ownership Consider two comparison cases –157nm and EPL (Scalpel) at the 70nm node –EUV and EPL (Scalpel) at the 50nm node –Compare both at mask usage's of 500 and 5000 wpm –ISMT Dec.99 - Rev. 4 assumptions (e.g. 25 x 25, 3rd yr, etc.) Analyze Cost of Ownership as a function of tool and mask cost Mark-Ups
i:\litho\013\Roadmap info\ITRS 07-11 27 Cost Conclusions Total R&D spending for one regional solution could approach one billion dollars in 2002 alone –Almost 2X previous spending rates –Finding both the funds and the necessary talented people may be biggest challenge of all Roadmap acceleration exacerbates business situation... fewer tools, more improvements over shorter time To make sufficient ROI suppliers may have to increase mark-up Increased tool and mask costs will drive up CoO at all mask usage levels
i:\litho\013\Roadmap info\ITRS 07-11 28 Lithography ITWG Report – 2000 Update Summary Technology Node Timing accelerated 1-2 years –130nm in 2001 90nm in 2004 –Not a consensus decision Puts major strain on entire lithography infrastructure New DRAM and MPU chip sizes allow smaller minimum field size and 5X option for advanced optical tools with 6-inch reticles Optical mask requirements for dense lines must be much tighter, based on latest MEF data Cost control and ROI continue to be major concerns for acceleration at 90nm – 45nm nodes
i:\litho\013\Roadmap info\ITRS 07-11 29 Acknowledgements We would like to express our most sincere gratitude and appreciation for the outstanding support and cooperation from the ITWG participants. EuropePaolo Canestrari Jan-Willem Gemmink JapanHiroshi Ohtsuka Masaru Sasago KoreaKi Ho Baik Joo-Tae Moon TaiwanY.C. Ku Anthony Yen USAGeorge Gomba Gil Shelden Lithography ITWG Report