In an exclusive interview with EE Times in his Menlo Park office, Yen showed the first wafers back from the fab for Niagara 2, set to ship in systems before the end of the year. He also discussed the issues Sun faces now that its longtime silicon partner, Texas Instruments, has decided to rely on foundries to develop next-generation semiconductor process technology.
Chief executive Jonathan Schwartz appointed Yen, a long time Sun veteran, to head up Sun Microelectronics in late March. Yen had led the group for several years beginning in 2001 until he was named to head a systems design group and later a storage division.
Sun plowed the chip group into a systems division under John Fowler until March. That's when Schwartz asked Yen to take the helm again, making it once again an independent unit that designs Sparc and related chips.
Part of Yen's charter is to "make our silicon intellectual property more available beyond our walls" said Yen, referring to Schwartz's philosophy of open collaboration. Schwartz praised the newly reformed semiconductor group in early April when it licensed its enhanced Ethernet technology to Marvell, saying the deal was a sign of things to come.
Finding partners to make Sun's chips at the 45nm and 32nm nodes is probably the biggest challenge Yen faces.
"Currently TI does everything for us," said Yen. "We tape out our designs and get fully packaged parts in return.
"For 20 years TI has been a fabulous partner. Trying to recreate that kind of partnership will be very challenging," he added.
The next steps in the transition for Sun are not yet clear, probably because TI is still working out the details of its silicon road map.
"My understanding is TI came to the conclusion their own design rules are not that different from what's being used by foundries. But for higher performance designs they do with us, I still need to find out what's the plan going forward," said Yen who had been in his new role just two weeks when EE Times interviewed him in mid April.
Sun's upcoming Niagara 2 and Rock processors are made in 65nm technology. However, the company has at least three designs in the works intended as follow ups to those products. Sun isn't saying just what process technologies those designs target.
"We have gone pretty far with TI working on the 45nm technology," said Yen. "I think that generation is well taken care of. Beyond 45nm on our end the work is at a very early stage and if there is any change in what we will do it will probably be at the generation beyond 45nm," Yen said.
A possible shift in fab partners could lead Sun to experiment with a new design flow such as customer-owned tooling. Sun tried a COT process in about 2002 working with United Microelectronics Corp. in Taiwan.
However, when UMC failed to get into production a new low-k dielectric material it licensed from IBM Corp., the project faced significant delays. That forced Sun's systems group to back away from the CPU being designed at UMC, and the Microelectronics group canceled its experiment with COT.
"Changing foundries is not an arbitrary decision," said Yen. "We want to develop a long term relationship. All the foundries have their strengths and weaknesses in technology and they carry different strategic implications," he added.
As for its CPU roadmap, Yen said Sun had a lot of architectural tricks still up its sleeve for the Rock chip aimed at database servers and future Niagara parts aimed at Web servers.
Rock will include "modern processor features up to now only being discussed in academic papersand the industry will get a new 'wow'" with some of the features planned for the third- and fourth-generation Niagara parts now in the works, Yen said.
Niagara 2 has eight cores that can handle 32 threads in parallel. It also integrates an enhanced Ethernet media access controller and a security accelerator block.
"All the features we will introduce in the Niagara and Rock families will keep the industry busy for the next five years. This is a very exciting period for people working on processors," Yen said.