EUV lithography making progress but still far from ready

After many years of delay, the semiconductor industry now hopes extreme ultraviolet (EUV) lithography will arrive in time for the 7nm node. EE Times reports progress is being made but notes the technology is still far from maturity because there's still no light source powerful and reliable enough for mass production.

ASML and its customer TSMC revealed at the Industry Strategy Symposium last week that they're now testing a 85W light source in prototype systems, which will soon be upgraded to 125W. ASML recently demonstrated a 185W light source and claims it can produce 250W models before the end of the year.

Current EUV prototype machines are running as much as 70 percent of the time and are capable of manufacturing 500-600 wafers a day. Clearly, progress is being made as this is a big step from where the technology was last year, but it's still a factor of 2-3 out from where it needs to be to be ready for mass production:

“We are a factor of 2-3 out from where we need to be,” said Frits van Hout, chief program officer for EUV at ASM at the event hosted by the SEMI trade group. Currently shipping prototype tools “will need to be field upgraded to be fully ready, but I would guess by the end of this year we should be at that point,” he added.

Chip makers currently hope they can start using EUV machines in production flows by sometime in 2018. At that point they would help lower cost for a second-generation of 7nm chips.

The good news is EUV is highly accurate with systems hitting some targets within fractions of a nanometer. But given the many delays around throughput and reliability it may require an upgrade of its numerical aperture to be of use at 5 or 3nm line widths. ASML is “discussing details with stakeholders of the configuration and timing of [such a] machine…we are taking steps to make it possible,” he said.

If ASML can perfect the technology on time, Intel and others are looking forward to adopt EUV on the 7nm node. Intel is expected to make a decision on whether it will use EUV on 7nm later this year.