In August, 2005, ISI’s MOSIS brokerage service will mark the 25th anniversary of a program that manufactures test prototypes of chips designed by student engineers free of charge.
How important was this program to Michael McCorquodale, Ph.D. (U. Michigan, 2004)?
McCorquodale (left) is now CEO/CTO of a new start- up company, Mobius Microsystems, that is commercializing a chip that grows directly out of his U-Michigan research. While a grad student, McCorquodale was able, with the help of MOSIS, to get three versions of his design fabricated – and version number three worked. In fact, it worked so well it won a prize at the Design Automation Conference in 2003, and is now on its way to becoming a Mobius product.
“The whole project has been MOSIS dependent,” he said. “When you’re a student, there aren’t a lot of options.” Without MOSIS, he says, as he finished his Ph.D. “we wouldn’t have anything except an interesting idea.” But with it, he said, “we had silicon we could demonstrate to investors and prospective customers. ”
McCorquodale is a standout case, to be sure, but multiply his experience by thousands for an idea of the impact of the program as it approaches its 25th birthday. In 2004, the year he received his Ph.D., MOSIS prototyped nearly 1000 chips for students across the country.
All told, between 1990 and 2003, some 66,539 students have learned chip design in MOSIS-associated programs, and a total of 13,734 designs have been realized, according to a detailed report on the program prepared by Richard Brown, a chip design expert formerly at the University of Michigan who is now dean of the University of Utah college of engineering.
“There are innumerable examples of students who have learned to design chips because the MOSIS service was there, and matured as VLSI engineers through being able to test chips they had designed,” Brown says.
In fact, notes Brown, in many cases “the courses they took would not have been offered without MOSIS.”
A dollar analysis makes the magnitude of the MOSIS contribution clear. In 2003, MOSIS fabricated a total of 852 student chips, 752 of them instructional, another 135 research projects. Had the students and researchers had to go out and pay market price to realize these chips, the total bill would have come to $6.7 million.
César Piña (right) is director of MOSIS, headquartered at ISI, which is part of the USC Viterbi School of Engineering, For decades, MOSIS has been facilitating commercial chip design by providing a secure, economical and reliable way of prototyping chips.
MOSIS contracts directly with commercial chip foundries for wholesale silicon “acreage,” and retails the subdivided space on an affordable non-profit basis. “MOSIS keeps the cost of fabricating prototype quantities low by aggregating multiple designs onto one mask set,” reads the organization’s fact sheet.
MOSIS has prototyped more than 50,000 chip designs for businesses, government agencies and universities, including the originals of many now widely used commercial chips, such as those used in Sun Microsystems SPARC and SGI’s MIPS systems.
These architectures grew out of the work of David Patterson, a UC Berkeley computer scientist, who divided his class into two teams who designed some of the world’s first RISC chips – architecture that later found its way into SPARC & MIPS.
The educational program dates back to August, 1980, when MOSIS began offering what would otherwise have been waste space on chip runs to students free.
After all paying customer have designs in place, in many runs, area remains on the silicon blank. Waiting for more designs to arrive would delay customers. Accordingly, the empty space is allocated, if and as available, to students. “It’s as if we were running a busline,” said Piña. “The bus leaves at a scheduled time, whether it’s empty or full. The student work goes in the empty seats.”
The process is not cost-free for MOSIS. Besides the work of placing the designs into the mask, MOSIS staff must deal with questions and make sure everything is according to specifications. “Our paying customers need little help on this,” said Piña. “They know the design rules. But the students are, often, coming in cold,” he continued – they know the theory of chip design, but haven’t actually had the experience of submitting a design for fabrication.
Piña estimates that answering such questions costs the brokerage an average of 1-2 man-weeks per run, an expense that is written off as a donation.
Between 1985 and 1996, DARPA and the NSF provided funding for such activity. “We were sorry to see that support end,” said Piña, “But we thought the program was too important not to continue.”
The professors and students taking advantage of the arrangement are grateful. Don Bouldin, a professor of electrical and computer engineering at the University of Tennessee, has been teaching chip design for more than 20 years, with students now working at Intel, Motorola, TI, and IBM. He says his students have submitted nearly 200 chips for fabrication by MOSIS under the program.
“It has been a highly motivating experience for my students.” Bouldin explained. Along with the satisfaction of having their work actually fabricated, the process “presents them with the realistic fear that the project might not work, and therefore causes them to exert extra effort in checking their work. Additionally, the experience of testing the fabricated chips and comparing those results to simulations is very valuable.”
Bouldin started a MOSIS users group that now has 3300 members, and organized a continuing series of biannual conference aimed at bringing together instructors and students using MOSIS. It can be a career saver for some students. Professor Steve Long of the UC Santa Barbara has been working with MOSIS as a researcher since the mid ’80s. Now, he reports, “I have 2 PhD students who are designing circuits to be submitted to MOSIS&hellip Both students are in their last year and have outlived their original funding source. MOSIS MEP generously has agreed to offer them space on some upcoming runs so they can verify their work and finish writing their dissertations.”
Finally, what goes around comes around in the most direct possible way for MOSIS. As a start-up entrepreneur, Michael McCorquodale no longer qualifies for MOSIS student chip making. But he still needs to have chips made to realize his designs for the product Mobius Microsystems is building.
So “now we’re a paying customer,” he reports. “We just did a chip. We got the silicon back through MOSIS.”
Published on May 25th, 2005
Last updated on August 9th, 2021