SAN JOSE, Calif. Amid a major expansion plan, Japan's e-Shuttle Inc. is moving to improve its direct-write e-beam capabilities. It is also exploring the future use of next-generation maskless tools from Mapper Lithography NV and other startups in the arena.
In 2006, e-Shuttle (Kawasaki) was established by Japan's Fujitsu Microelectronics Ltd. and Advantest Corp. in order to provide IC prototyping services and low-volume chip manufacturing for customers. The venture uses Advantest's direct-write electron-beam tool, dubbed the F3000.
At present, e-Shuttle focuses on producing ASICs and high-speed SRAMs for customers, said Shinji Sugatani, general manager of e-Shuttle. The company's customers "are mostly in Japan," he told EE Times. "We want to expand that."
One of the company's customers is U.S.-based eASIC Corp., a provider of structured ASICs. With the help of e-Shuttle, the ASIC provider said that it has surpassed 100 design wins in only 18 months for its family of 90-nm devices.
For some time, eASIC has claimed that there are little or no NRE and mask costs associated with its Nextreme family of ASICs. ''The cost of traditional ASIC customization became prohibitive for the majority of applications and designers. eASIC's zero mask-charge Nextreme devices have changed that landscape,'' said Ronnie Vasishta, president and CEO of eASIC (Santa Clara, Calif.).
Direct-write e-beam services offered by e-Shuttle, TSMC and others could indeed change the landscape for ASICs and related devices. Traditional e-beam tools write transfer design data directly onto the wafer and exposes it, thereby eliminating the photomask.
''The rapidly rising costs and increasingly complex design cycle for advanced standard cell and SoC products has forced many potential customers into postponing or canceling projects, or seeking alternatives such as FPGA prototyping in order to initiate their designs,'' according to a paper from e-Shuttle.
''Higher reticle prices and other factors have had a measurable impact,'' according to the paper. ''The benefits of e-beam lithography are illustrated by reviewing reticle costs, which are some six times higher for designs built using 65-nm processes technology than they were at 130-nm. And at 45-nm process technology, reticle costs will escalate to 10 times the cost at 130-nm. For the 65-nm process generation, a mask set is priced at $2 million, too high for prototyping.''
Enter e-Shuttle. After moving into 90-nm production, e-Shuttle is now processing 65-nm devices. E-Shuttle is also working on a 40-nm technology, with plans to offer this capability by the end of fiscal 2008.
The devices are processed via the F3000 e-beam tool from Advantest (Tokyo). In addition, e-Shuttle will expand its capacity by installing a second F3000 e-beam tool next month. Supporting 300-mm wafers, Advantest's F3000 is said to pattern designs down to the 40-nm node. It has a dimensional accuracy of less or equal to 7-nm and an overlay accuracy of less or equal to 20-nm.
The F3000 makes use of a block exposure system. ''Block mask is an important technology used to reduce the volume of drawing data. E-Shuttle prepares basic master patterns at the same time the technology is developed, and sets the patterns in (e-beam direct-write) equipment,'' according to e-Shuttle. ''Standard cell or SRAM ICs can be drawn by using (a) block mask. This method also increases the precision of the pattern as the measurement of the mask is pre-determined."
Advantest and e-Shuttle are making some enhancements to the F3000, including a more stable mechanism and a lower aberration lens. But despite the improvements, the tool will still have an overall throughput of only about 0.5 wafers per hour. With its new shuttle service, overall throughputs can be increased to about 1 wafer an hour.
This makes e-beam tools a probative technology in mainstream production fabs. Direct-write is, however, being use in the development of compound semiconductor devices.
But in fact, the problem with e-beam tools is that they are costly and slow in terms of throughput. This has prompted interest in a new class of maskless lithography tools from a number of startups. The technology, sometimes called ML2, makes use of multiple beams in a system to boost throughputs.
E-Shuttle is keeping a close eye on the ML2 landscape, especially the developments at Mapper Lithography. The Dutch-based company is developing a multi-beam e-beam tool and has received funding from Taiwan Semiconductor Manufacturing Co. Ltd. (TSMC). The silicon foundry giant has expressed interested in using Mapper's tools for ASIC production in the future.
"We are very interested in Mapper," Sugatani said. E-Shuttle may use ML2 tools from Mapper or others in the future, but the IC prototyping service company has not made any formal announcements in the arena. The company insists that Advantest is its e-beam vendor of choice.