12 Oct 2011
The world's dominant lithography equipment supplier aims for commercial productivity levels by mid-2012, after problems with light sources.
After a delay caused by under-investment in extreme ultraviolet (EUV) light source development, the semiconductor lithography equipment vendor ASML has redefined its productivity roadmap for the technology.
Executives from the Netherlands-based company, which commands a market share of around 70% in lithography tools, focused largely on EUV developments in their latest quarterly financial report, saying that while EUV imaging and overlay criteria are now production-worthy, the source output power needed for high-volume manufacturing (HVM) was still lagging.
As a result, the company expects to reach the commercially viable productivity level of 60 wafers/hour with EUV in the summer of 2012 – at which point it expects to begin building production EUV tools for shipment. ASML’s light-source partners Cymer and Ushio have now reached an output power level of 30 W with a high duty cycle, while Gigaphoton has been scheduled to deliver a 100 W source to ASML this month.
To get to the power levels required for production use by device makers (the true HVM target is 250 W), significant improvements are still required. ASML identified three key areas for increasing the output power, including the use of a “pre-pulse” step to improve the efficiency of generating EUV radiation.
In its tools, EUV radiation is produced by firing an industrial CO2 laser at droplets of tin – a highly inefficient process that has been likened by those developing the technology to using a nuclear power station to power a village. Conversion efficiencies of less than 5% are typical, meaning that the vast majority of the multi-kilowatt laser emission is wasted.
But as reported by optics.org earlier this year, Gigaphoton – now under the full ownership of Komatsu – has been developing a pre-pulse technology whereby the tin droplets are first hit by another laser. Firing an Nd:YAG beam at the tin droplets causes them to nebulize, generating a metallic “mist” that effectively provides a bigger target for the high-power laser to hit. Gigaphoton says that more EUV energy is produced as a result.
As well as adopting the pre-pulse approach, ASML says that EUV light filtering must be optimized, and it also needs to see an improvement in duty cycles for continuous production. Speaking to investors to discuss the company’s latest quarterly financial results, CEO Eric Meurice said that the main source challenges have now been identified, and the period between now and the end of 2011 appears to be a critical one in the evolution of the technology as those are addressed.
With EUV productivity levels now at around 15-20 wafers per hour, Meurice needs to see 60 wafers per hour reached by mid-2012 – at which point ASML expects to be assembling EUV tools at a rate of one per month for the rest of 2012 and throughout 2013. With an expected price tag of between €65 million and €75 million, the equipment will cost close to three times the average selling price of ASML’s current lithography tools.
The CEO went on to explain that the deployment of EUV lithography among the leading semiconductor makers will be quite different to the step-change migration from one node to the next that has characterized the industry over the past couple of decades.
Instead, chip manufacturers will adopt the technology gradually, using it alongside existing tools but only for certain critical layers. “It’s not a question of node; it’s a question of layers-per-node,” he said. In memory chip applications, that might only be two or three layers per wafer initially, but for logic chips there could be more than ten such layers, Meurice explained.
Too early to call 2012
Commenting on the wider macro-economic environment, and how that will impact ASML sales in 2012, Meurice stressed that it was still “too early” to call the overall level of capacity expansion needed next year. Although ASML is not yet providing any financial guidance for 2012, what it is expecting is a year of technological transition as manufacturers begin to adopt EUV tools, ahead of production insertions in the first half of 2013.
While 2012 demand still looks uncertain, both Meurice and CFO Peter Wennink said that the current malaise caused by the eurozone debt crisis and worries about the US economy tipping back into recession presented a markedly different situation to late 2008 – when the shock of the credit crunch suddenly “froze” the market for ASML’s tools for six months. Almost exactly three years on from that crunch, ASML’s senior team says that its customers have very clear roadmaps and there is no sign of any repeat.
With a lead time of around six months for its conventional systems, and at least double that for its EUV systems, the changes in order patterns that ASML witnesses take at least a couple of quarters to filter through to sales turnover. As a result, the company is certain to post a record year for 2011, despite a significant slowdown in orders in Q3.
In the first three quarters of this year, ASML has already recorded sales of nearly €4.5 billion, and it is expecting revenues of around €1.1 billion in the closing quarter. In early trading following the latest results announcement, where it posted better-than-expected sales of €1.46 billion and bookings of €514 million, ASML’s New York-listed stock rose by close to 10%.