This paper describes the development and evolution of the critical architecture for a laser-produced-plasma (LPP) extreme-ultraviolet (EUV) source for advanced lithography applications in high volume manufacturing (HVM). In this paper we discuss the most recent results from high power sources in the field and testing on our laboratory based development systems, and describe the requirements and technical challenges related to successful implementation of those technologies on production sources. System performance is shown, focusing on pre-pulse operation with high conversion efficiency (CE) and with dose control to ensure high die yield. Finally, experimental results evaluating technologies for generating stable EUV power output for a high volume manufacturing (HVM) LPP source will be reviewed.
Laser produced plasma (LPP) systems have been developed as the primary approach for use in EUV scanner light sources for optical imaging of circuit features at 20nm nodes and beyond. This paper provides a review of development progress and productization status for LPP extreme-ultra-violet (EUV) sources with performance goals targeted to meet specific requirements from ASML. We present the latest results on power generation and collector
protection for sources in the field operating at 10W nominal power and in San Diego operating in MOPA (Master Oscillator Power Amplifier) Prepulse mode at higher powers. Semiconductor industry standards for reliability and source availability data are provided. In these proceedings we show results demonstrating validation of MOPA Prepulse operation at high dose-controlled power: 40 W average power with closed-loop active dose control meeting the requirement for dose stability, 55 W average power with closed-loop active dose control, and early collector
protection tests to 4 billion pulses without loss of reflectivity.
Laser produced plasma (LPP) systems have been developed as the primary approach for the EUV scanner
light source for optical imaging of circuit features at sub-22nm and beyond nodes on the ITRS roadmap. This
paper provides a review of development progress and productization status for LPP extreme-ultra-violet
(EUV) sources with performance goals targeted to meet specific requirements from leading scanner
manufacturers. We present the latest results on exposure power generation, collection, and clean transmission
of EUV through the intermediate focus. Semiconductor industry standards for reliability and source
availability data are provided. We report on measurements taken using a 5sr normal incidence collector on a
production system. The lifetime of the collector mirror is a critical parameter in the development of extreme
ultra-violet LPP lithography sources. Deposition of target material as well as sputtering or implantation of
incident particles can reduce the reflectivity of the mirror coating during exposure. Debris mitigation
techniques are used to inhibit damage from occuring, the protection results of these techniques will be shown
over multi-100's of hours.
This paper describes the development of laser-produced-plasma (LPP) extreme-ultraviolet (EUV) source
architecture for advanced lithography applications in high volume manufacturing. EUV lithography is
expected to succeed 193 nm immersion technology for sub-22 nm critical layer patterning. In this paper we
discuss the most recent results from high qualification testing of sources in production. Subsystem
performance will be shown including collector protection, out-of-band (OOB) radiation measurements,
and intermediate-focus (IF) protection as well as experience in system use. This presentation reviews the
experimental results obtained on systems with a focus on the topics most critical for an HVM source.
Laser produced plasma (LPP) systems have been developed as a viable approach for the EUV scanner light sources to
support optical imaging of circuit features at sub-22nm nodes on the ITRS roadmap. This paper provides a review of
development progress and productization status for LPP extreme-ultra-violet (EUV) sources with performance goals
targeted to meet specific requirements from leading scanner manufacturers. The status of first generation High Volume
Manufacturing (HVM) sources in production and at a leading semiconductor device manufacturer is discussed. The
EUV power at intermediate focus is discussed and the lastest data are presented. An electricity consumption model is
described, and our current product roadmap is shown.
This paper describes the development of laser-produced-plasma (LPP) extreme-ultraviolet (EUV) source architecture
for advanced lithography applications in high volume manufacturing. EUV lithography is expected to succeed 193nm
immersion technology for sub-22nm critical layer patterning. In this paper we discuss the most recent results from high
EUV power testing and debris mitigation testing on witness samples and normal incidence collectors. Subsystem
performance will be shown including the CO2 drive laser, debris mitigation, normal incidence collector and coatings,
droplet generation, laser-to-droplet targeting control, intermediate-focus (IF) metrology and system use and experience.
In addition, a number of smaller lab-scale experimental systems have also been constructed and tested. This
presentation reviews the experimental results obtained on systems with a focus on the topics most critical for an HVM
Laser produced plasma (LPP) systems have been developed as a viable approach for the EUV scanner light source to support optical imaging of circuit features at sub-22nm and beyond nodes on the ITRS roadmap. This paper provides a review of development progress and productization status for LPP extreme-ultra-violet (EUV) sources with performance goals targeted to meet specific requirements from leading scanner manufacturers. The status of first generation High Volume Manufacturing (HVM) sources in production and of prototype source operation at a leading scanner manufacturer is discussed. The EUV power at intermediate focus is discussed and the lastest data is presented. An electricity consumption model is described, and our current product roadmap is shown.
High productivity is a key requirement for today's advanced lithography exposure tools. Achieving targets for
wafers per day output requires consistently high throughput and availability. One of the keys to high availability
is minimizing unscheduled downtime of the litho cell, including the scanner, track and light source. From the
earliest eximer laser light sources, Cymer has collected extensive performance data during operation of the
source, and this data has been used to identify the root causes of downtime and failures on the system. Recently,
new techniques have been developed for more extensive analysis of this data to characterize the onset of typical
end-of-life behavior of components within the light source and allow greater predictive capability for identifying
both the type of upcoming service that will be required and when it will be required.
The new techniques described in this paper are based on two core elements of Cymer's light source data
management architecture. The first is enhanced performance logging features added to newer-generation light
source software that captures detailed performance data; and the second is Cymer OnLine (COL) which
facilitates collection and transmission of light source data. Extensive analysis of the performance data collected
using this architecture has demonstrated that many light source issues exhibit recognizable patterns in their
symptoms. These patterns are amenable to automated identification using a Cymer-developed model-based fault
detection system, thereby alleviating the need for detailed manual review of all light source performance
information. Automated recognition of these patterns also augments our ability to predict the performance
trending of light sources.
Such automated analysis provides several efficiency improvements for light source troubleshooting by providing
more content-rich standardized summaries of light source performance, along with reduced time-to-identification
for previously classified faults. Automation provides the ability to generate metrics based on a single light source,
or multiple light sources. However, perhaps the most significant advantage is that these recognized patterns are
often correlated to known root cause, where known corrective actions can be implemented, and this can therefore
minimize the time that the light source needs to be offline for maintenance. In this paper, we will show examples
of how this new tool and methodology, through an increased level of automation in analysis, is able to reduce
fault identification time, reduce time for root cause determination for previously experienced issues, and enhance
our light source performance predictability.
Leading-edge scanners in fabs worldwide have particularly high system utilization and require peak levels of system
throughput and availability. Laser gas exchanges typically occur daily on these systems (or every 100M pulses or less),
with each exchange lasting up to 20 minutes. This downtime has a direct negative effect on availability, and if it is
reduced, the productivity of the litho cell increases.
This paper will outline the immediate success fabs have experienced after equipping scanners with Cymer's Gas
Lifetime eXtension (GLX<sup>TM</sup>) technology, which increases scanner availability by extending the time between excimer
laser gas exchanges by a factor of more than 10. To date, more than 100 leading-edge scanners feature Cymer's GLX
technology, which has improved light source availability by more than 1.5 percent. Moreover, multiple chipmakers
report more than 2 percent improvement in litho cell productivity due to GLX, corresponding to 2000 wafers/month
increase for a 100,000 wafers/month fab. The increase in measured productivity is the leveraged benefit of reducing
process interruptions around the refill cycle
GLX technology extends the shot-based interval between gas refills to 1 billion pulses for Cymer's XLA light sources,
and provides excellent stability in key optical performance parameters, such as bandwidth and dose stability over the
entire gas life. This paper will provide extensive performance data during extended light source operation on litho cells
equipped with GLX technology, and multiple use scenarios will be examined, including usage at memory and logic fabs.
The paper will also discuss the performance of GLX2<sup>TM</sup> technology which further extends the maximum time between
light source gas exchanges from 1B pulses to 2B pulses, and reduces downtime associated with gas refills by a factor of
20. The stability and productivity benefits of this new technology can be realized under all light source utilization
scenarios. With GLX2, the refill interval at high utilization chipmakers is 3 weeks, and 4-8 weeks at lower utilization
customers. Metrics illustrating the success of each of these capabilities will be presented. The second-generation of GLX
technology was launched in July 2008 after chipmakers responded favorably to GLX performance metrics.
Increasing productivity demands on leading-edge scanners require greatly improved light source availability. This
translates directly to minimizing downtime and maximizing productive time, as defined in the SEMI E10 standard.
Focused efforts to achieve these goals are ongoing and Cymer has demonstrated significant improvements on production
This paper describes significant availability improvements of Cymer light sources enabled by a new advanced gas
management scheme called Gas Lifetime eXtensio<sup>TM</sup> (GL<sup>TM</sup>) control system. Using GLX, we have demonstrated the
capability of extending the pulse-based interval between full gas replenishments to 1 billion pulses on our XLA light
sources, as well as significant extension in the time-based interval between refills. This represents a factor of 10X
increase in the maximum interval between full gas replenishments, which equates to potential gain of up to 2% in
productive time over a year for systems operating at high utilization.
In this paper, we provide performance data on extended (1 billion pulse) laser operation without full gas replenishment
under multiple actual practical production environments demonstrating the ability to achieve long gas lives with very
stable optical performance from the laser system. In particular, we have demonstrated that GLX can provide excellent
stability in key optical performance parameters, such as bandwidth, over extended gas lives. Further, these stability
benefits can be realized under both high and low pulse accumulation scenarios.
In addition, we briefly discuss the potential for future gas management enhancements that will provide even longer term
system performance stability and corresponding reductions in tool downtime.
Increasing throughput demands on leading edge scanners are requiring greatly improved light source availability. This
translates directly to minimizing <i>downtime </i>and maximizing <i>productive time</i>, as defined in the SEMI E10 standard. One
positive contributor to improving productive time is the minimization of the light source stoppage for entire Halogen
gas replenishment. This paper describes availability improvements of Cymer XLA and 7000 series light sources by
using advanced gas management schemes to minimize entire gas replenishment impact to productive time. Recent
augmented gas control algorithms have demonstrated multiple times extension of gas life through advanced gas
replenishment methods and higher performance estimators. Along with these improvements to gas management, major
efforts in light source fault reduction, module lifetime extension and optimization of module replacement, will provide
significantly increased combined light source\scanner availability.
The variation of CD with pitch, or Optical Proximity Effect (OPE), in an imaging system shows a behavior that is characteristic of the imaging and process conditions and is sensitive to variations in those conditions. Maintaining stable process conditions can improve the effectiveness of mask Optical Proximity Correction (OPC). One of the factors which affects the OPE is the spectral bandwidth of the light source. To date, passive bandwidth stabilization techniques have been effective in meeting OPE control requirements. However, future tighter OPE specifications will require advanced bandwidth control techniques. This paper describes developments in active stabilization of bandwidth in Cymer XLA and 7010 lasers. State of the art on board metrology, used to accurately measure E95 bandwidth, has enabled a new array of active control solutions to be deployed. Advanced spectral engineering techniques, including sophisticated control algorithms, are used to stabilize and regulate the bandwidth of the light source while maintaining other key performance specifications.
The first generation MOPA-based ArF laser XLA-100 was introduced in January 2003 in response to the needs of the high NA ArF scanners for higher power and narrower spectral bandwidth. The second generation product XLA-105 was introduced in early 2004. This paper presents our third generation MOPA-based ArF laser product XLA-200 that is designed and engineered to meet the light source requirements of the ArF immersion lithography. It is expected to be used for 65-nm and 45-nm volume production of semiconductor devices. The XLA-200 is capable of producing a 60W of ultra-line-narrowed 193nm light with the FWHM bandwidth of less than 0.15pm and the E95% integral bandwidth of less than 0.35pm. It features state-of-the-art on-board bandwidth metrology tool that measures E95% bandwidth as well as FWHM. Real-time accurate bandwidth information can be utilized for lithography exposure tool feedback control. The improved dual-chamber laser gas control ensures excellent bandwidth stability, which enables tighter CD control. Together with a lower cost of ooperation, the XLA-200 sets a new performance level for the dual chamber 193nm light source for microlithography.