This chapter describes the development of a laser-produced-plasma (LPP) EUV source for advanced lithography applications in high-volume manufacturing (HVM) of semiconductor devices. EUVL is expected to succeed 193-nm immersion multipatterning technology for sub-10-nm critical-layer patterning. The most recent results from high-power systems targeted at the 250-W configuration are described to date. The requirements and technical challenges related to successful implementation of these technologies are outlined for the reader. Development of second-generation LPP light sources for ASML’s NXE:3300B, NXE:3350B, and NXE:3400B (Fig. 3A.1) EUV scanners is complete, with approximately 15 units installed and operational at chipmaker customers. Different aspects and performance characteristics of the sources as well as related research and development progress at our facilities were already described in detail in several earlier publications. We have described initial dose stability results, power scaling and availability data for ASML’s NXE:3100 first-generation sources, and have reported on several new development results. Ten first-generation NXE:3100 sources (Fig. 3A.2) have been operational for over five years; five systems were deployed to customers for use in process development at early adopters of EUVL technology. Key features of the NXE platform as well as scanner performance during the system introduction have already been reviewed in detail. In this chapter, we report on the characterization of source components that are critical to achieve the higher power required for the second-generation light sources to support EUV scanners at chipmaker production facilities. The NXE:3300B source drive laser uses a master oscillator power amplifier (MOPA) laser architecture with a pre-pulse mode of operation. The pre-pulse conditions the target from a liquid tin (Sn) droplet to a lower-density target at the focal plane of the laser focusing optics. A main (high-energy) pulse from the drive laser is then focused onto the prepulse-conditioned target, creating a highly ionized plasma that emits EUV radiation at wavelengths around 13.5 nm.