SAN JOSE, Calif. – At the SPIE Advanced Lithography conference here, ASML Holding NV disclosed more details about its progress with extreme ultraviolet (EUV) lithography.
ASML’s pre-production EUV tool is said to be patterning images down to 18-nm, but as reported,
the machine throughput remains problematic due to issues with the power sources. The company also tweaked the specifications for the follow-on, product-worthy tool, which is due to ship in 2012.
ASML has recently shipped the world's first pre-production EUV lithography tool to a customer, reportedly Samsung Electronics Co. Ltd., sources said. That tool from ASML is called the NXE:3100, which is using a light source from Cymer Inc.
ASML has shipped a second NXE:3100 to IMEC, a Belgium R&D organization. The NXE:3100 is said to have a resolution of 27-nm, a numerical aperture (NA) of 0.25, a field size of 26-nm, an overlay of 4-nm and flare at less than 5 percent.
The tool reportedly runs about $100 million-each. To date, ASML has garnered a staggering $1 billion worth of business from EUV tool orders alone.
The NXE:3100 has demonstrated the ability to pattern 27- and 24-nm lines and spaces and 26-nm and 30-nm contact holes, said Christian Wagner, senior product manager at ASML, in a presentation at SPIE.
Initially, Samsung is reportedly looking to use EUV for DRAM production. One of the issues is to scale the dense contact holes without going to double patterning-a move that could save production costs.
The NXE:3100 has demonstrated the ability to print 32- and 40-nm dense contact holes, Wagner said. Using dipole resolution techniques, the system has demonstrated the ability to print images down to 20-nm, he said. In logic, the machine was said to pattern an SRAM down to 18-nm, he said.
The stated goal of the tool is to have an overall throughput of 60 wafers an hour by year’s end. But right now, the tool has a throughput of 5 wafers an hour. In other words, the tool requires a ''10X’’ improvement in the power source-or about 100 watts-to meet the stated goal of running 60 wafers per hour, he said.
To become a viable business model for fab tool vendors, EUV must have a sustained throughput of 80 wafers an hour, according to a KLA-Tencor executive.
At present, ASML has two power source suppliers for the tool: Cymer Inc. and Ushio Inc. Cymer has devised a power source based on laser-produced plasma (LPP) technology. At present, Cymer’s LPP source is running at a sustained power of 11 Watts, according to ASML.
Rival Ushio is developing a power source based on electric discharge technology. At present, the source has demonstrated 12 watts of power, according to ASML. Another vendor, Gigaphoton Inc., has demonstrated 20 Watts of power.
ASML has shipped two NXE:3100 tools. In total, it has six orders for the machine. Following the NXE:3100, the company has been developing the previously-announced NXE:3300, a full-blown production machine.
The first version, dubbed the NXE:3300B, has an NA of 0.33 and a resolution of 0.22-nm. Originally, the NXE:3300B had an NA of 0.32, but the company has bumped up the NA specification to 0.33.
The stated goal for the tool is to have a sustained throughput of 125 wafers an hour, meaning that a 250 Watt power source is needed for the system. Shipments are due in the first half of 2012. ASML has ten orders for the system.