Huawei’s Testing of a Domestic EUV Light Source: LDP vs. LPP Methodologies

Introduction

• Huawei is reportedly testing a domestically developed EUV (Extreme Ultraviolet) machine using the Laser Induced Discharge Plasma (LDP) method.
• ASML currently uses the Laser Produced Plasma (LPP) method.
• Claims suggest LDP is more efficient, smaller, simpler, and has better energy efficiency.

EUV Light Source Overview

• EUV Light Production: The goal is to produce 13.5 nm light.
• LPP Method:
  • Uses a CO2 laser to hit a tin droplet twice, forming a plasma that emits the desired light.
  • Light passes through a complex optical system with multiple mirror reflections.
  • Efficiency issue: Less than 70% of the light is reflected at each mirror.

Early EUV Development

• LPP Challenges:
  • Involves unstable CO2 laser and microscopic tin targets.
  • Vendors explored various light generation methods.
• DPP Method (Discharge Produced Plasma):
  • Produces light by discharging electric current between electrodes.
  • Magnetic fields compress and heat the fuel to emit UV radiation.
  • Historical Connection: Similar to Z pinch used in 1950s nuclear fusion research.

DPP and LDP Historical Context

• Early 2000s:
  • DPP Investigations: By EUVA in Japan and Philips Extreme UV using Xenon and tin fuels.
  • Challenges: Difficulty in repeating high-frequency discharges without significant thermal damage.

LDP Method Development

• LDP Process:
  • Uses rotating tin supply discs and energy storage capacitors as electrodes.
  • Tin films on discs are laser-pulsed to create a pre-plasma, followed by electric discharge.
  • Offers potential efficiency and debris management benefits due to continuous wheel rotation.

Market and Technical Developments

• 2005-2010:
  • Usio Group acquired Philips Extreme UV, continued LDP research.
  • Demonstrated LDP source with scalable output power.
• Technical Challenges:
  • LDP’s scaling limitations in achieving high output power compared to LPP.
  • Potential issues with larger plasma size rather than increased brightness.

Current Developments and Future Prospects

• ASML’s Strategic Decision:
  • Chose LPP over LDP due to better power scaling.
  • Continued improvements with ASML achieving 740 watts of EUV power.
• China’s Progress:
  • Pursuing various EUV light source methods, including LDP.
  • Significant investment and research efforts likely to yield results.

Conclusion

• Economic Competitiveness:
  • Initial Chinese EUV machines may be less competitive but potentially innovative.
• Strategic Implication for ASML:
  • Potential need to reduce gross margins to counter Chinese advancements.

Note: The speaker expresses uncertainty about the exact details of Huawei’s technology, reflecting on historical development and potential future directions in EUV technology.