25 Years of SI

We at Semiconductor International are celebrating our 25th anniversary this month. Looking back over the years (I've been fortunate enough to be on staff close to 22 of those 25 years), it's amazing to me how much the industry has accomplished during that time. We've seen huge increases in chip functionality, in roughly the same area of silicon. DRAMs progressed from 16 kb to 1 Gb, and microprocessors from chips with a few thousand transistors to ones with close to a billion.

Yet, it's remarkable how little has changed. The industry still relies on CMOS transistors that, although quite a bit smaller, are very similar to those 25 years ago. Optical lithography, ion implantation, physical vapor deposition and dielectric etch are still in widespread use, and silicon remains the substrate of choice.

In truth, the industry has been fairly conservative. Now, of course, those days appear to be over, with a variety of new materials in the early stages of implementation — high- and low-k dielectrics, SOI, strained silicon, metal gates, ruthenium barriers — as well as new transistor designs, all on top of a transition to a new wafer size (that in retrospect should have probably been delayed about 10 years). The trick will be to implement all these changes simultaneously, in a cost-effective way, without degrading reliability.

But I think the biggest change in the industry has not been so much technology-related, but in how information is shared. In the early days, as we researched and wrote articles on various aspects of semiconductor manufacturing, it was almost impossible to get information from companies such as IBM or Texas Instruments. Manufacturing know-how was considered a competitive edge and a closely guarded secret.

That changed rather dramatically 10 years ago, with the introduction of the National Technology Roadmap for Semiconductors (NTRS), which has since evolved into the International Technology Roadmap for Semiconductors (ITRS). It's hard to describe how I felt the first time I saw the roadmap: in some ways I felt validated, since what the roadmap said was most important was exactly what we'd been covering in Semiconductor International since our inception (I originally thought the roadmap would focus mostly on design issues). It also filled in the blanks for me in several areas — it was not just drinking from the fountain of knowledge, but swimming in it, splashing in it, trying to get everyone else wet. Eureka!

I still get excited by the roadmap. In fact, a new edition was just released and I urge everyone to study it carefully. In this issue, we provide an excerpt listing the near-term "grand challenges" defined in the roadmap, but the entire document is posted on the web at http://public.itrs.net. New this year is the addition of emerging research devices (non-classical CMOS) and wireless technology requirements.

As excited as I am about the roadmap, however, I still have some reservations. In many ways, it has helped take semiconductor manufacturing know-how from a closely guarded secret to an easily achieved commodity (for anyone — or any country — with a few billion dollars to spend). It could also conceivably stifle creative thinking, creating a herd of technical lemmings blindly following Moore's Law into the abyss of technically achievable but economically idiotic. The roadmappers, of course, have considered this and clearly state: "Despite this need to provide guidance, the roadmap participants are continually pursuing new ways to prevent the roadmap itself from being interpreted as limiting the range of creative approaches to further advance microelectronics technology."

To me, the introduction of the first roadmap was the most important milestone of the past 25 years, but what do other people remember? In a special supplement to this issue, we provide some varied personal retrospectives that I think you'll find interesting. Also, what's the fun of looking back without trying to look 25 years into the future? We tackle that, and also provide a look at what top analysts expect the year to bring .

To all, thanks for your support over the years. It's been a fun trip. With roadmap clutched tightly in hand, I'm looking forward to an even more adventurous ride in the future.