In this paper, we provide an overview of various challenges and their solutions for scaling laser-produced-plasma (LPP) extreme-ultraviolet (EUV) source performance to enable high volume manufacturing. We will discuss improvements to source architecture that facilitated the increase of EUV power from 100W to >200W, and the technical challenges for power scaling of key source parameters and subsystems. Finally, we will describe current power-scaling research activities and provide a forward looking perspective for LPP EUV sources towards 500W.
We present highlights from plasma simulations performed in collaboration with Lawrence Livermore National Labs. This modeling is performed to advance the rate of learning about optimal EUV generation for laser produced plasmas and to provide insights where experimental results are not currently available. The goal is to identify key physical processes necessary for an accurate and predictive model capable of simulating a wide range of conditions. This modeling will help to drive source performance scaling in support of the EUV Lithography roadmap. The model simulates pre-pulse laser interaction with the tin droplet and follows the droplet expansion into the main pulse target zone. Next, the interaction of the expanded droplet with the main laser pulse is simulated. We demonstrate the predictive nature of the code and provide comparison with experimental results.
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.
Multiple NXE:3300 are operational at customer sites. These systems, equipped with a Numerical Aperture (NA) of 0.33, are being used by semiconductor manufacturers to support device development. Full Wafer Critical Dimension Uniformity (CDU) of 1.0 nm for 16nm dense lines and 1.1 nm for 20nm isolated space and stable matched overlay performance with ArF immersion scanner of less than 4nm provide the required lithographic performance for these device development activities. Steady progresses in source power have been achieved in the last 12 months, with 100Watts (W) EUV power capability demonstrated on multiple machines. Power levels up to 90W have been achieved on a customer machine, while 110W capability has been demonstrated in the ASML factory. Most NXE:3300 installed at customers have demonstrated the capability to expose 500 wafers per day, and one field system upgraded to the 80W configuration has proven capable of exposing 1,000 wafers per day. Scanner defectivity keeps being reduced by a 10x factor each year, while the first exposures obtained with full size EUV pellicles show no appreciable difference in CDU when compared to exposures done without pellicle. The 4th generation EUV system, the NXE: 3350, is being qualified in the ASML factory.
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.