Last week Hiroshi Ito, co-inventor of the chemically amplified resist (along with C. Grant Willson and Jean Fréchet), passed away after a long illness. Dr. Ito was working as a post-doc under Grant Willson at IBM when they developed the concept and the first example of a chemically amplified photoresist in 1980, now the dominant technology for semiconductor manufacturing. Dr. Ito became an IBM fellow in 2008.
Last Saturday I attended commencement ceremonies at my alma mater, Rose-Hulman Institute of Technology, a small science and engineering college in Terre Haute, Indiana. It is the first time I have sat through a graduation ceremony at Rose since my own graduation way back in 1982. It was a bit different this time, seeing it from the outside, so to speak. The graduating class of ‘09 was quite a bit bigger than in ’82, and as a result the ceremony quite a bit longer. The commencement speaker was a bit different as well.
I don’t remember the name of the guy who spoke at my college graduation, but I know why he was chosen. He was a Rose grad whose most famous contribution to the engineering profession was the invention of the 2 liter plastic soda bottle. And he spoke about what he knew – how he invented the process for making those bottles. Inspiring.
This year was a little different. The national reputation of Rose-Hulman has grown in the past 27 years, in large part due to ten years of being ranked #1 by US News and World Report in its category (engineering schools that don’t offer PhDs). As a result, the prominence of commencement speakers has also grown, with the governor of Indiana, Mitch Daniels, Jr., giving this year’s speech.
It started off as exactly the kind of commencement address one would expect, with humorous anecdotes, praise for Rose and its graduates, and calls for citizenship. But a politician with a large audience is sorely tempted, and the governor finished with a 15 minute tirade against the global warming “conspiracy”. Calling climate scientists “theologians” and their belief in global warming “a religion”, he lambasted them as graduates of “PC University” who refused to listen to honest skeptics like himself. Quoting the noted climate authority Michael Crichton (he wrote a novel on the subject, after all), he said “scientific consensus is the last refuge of scoundrels”.
Wow. I guess Governor Daniels thinks that science is too important to be left to the scientists. Fortunately, we have politicians like him to help us make sense of it all (making use, I am sure, of the well-deserved reputation of politicians for the reasoned and determined pursuit of truth regardless of the impact on personal or political gain). I feel cooler already.
For any serious basketball fan, the NCAA tournament of 1979 has to stand out as possibly the best one ever, with the final match arguably the best college basketball game ever played. Indiana State University and Larry Bird went undefeated that season until they were finally bested by Michigan State and Magic Johnson, 75-64. Being that game’s 30 year anniversary, and with Michigan State once again making it to the National Championship, there has been much talk lately of that great contest of March 26, 1979. I’d like to share my recollections, not of the game, but of its aftermath.
Indiana State University (ISU) is located in Terre Haute, a town that is most impressive in being completely unimpressive. So when its equally unimpressive state university began winning basketball games, the town took notice. I was a freshman that year at a small college on the other side of town, Rose-Hulman Institute of Technology. Basketball was the last thing on my mind – surviving my first year of chemistry, physics and calculus consumed all of my mental energy (and most of my sleep). Still, it was hard to escape the basketball excitement that was engulfing the town that spring. When ISU made it to the National Championship game, Terre Haute knew it would be an historic event for the city. A victory parade down Wabash Avenue was planned for the evening after the big game, and my roommates and I decided that studying could wait that night.
We drove into town soon after the ISU loss (I didn’t even watch the game), hearing on the radio that the “victory” parade would go on as planned. The parade went on, but it was anything but “as planned”. We parked a few blocks off the main drag and lined up along Wabash Ave. to watch. Within minutes of the start of the parade, things went completely crazy. The lone police car in the parade was soon covered with people and the cop inside wisely fled the scene as his car bobbed up and down under the feet of a dozen people jumping in unison. Street signs and traffic lights started toppling and windows started breaking. A bonfire was lit in the middle of the road as a van from the local radio station blared rock music to the crowd. I was witnessing a full-fledged riot.
My friends and I were in complete disbelief (none of us were serious basketball fans, so we didn’t get what all the fuss was about). As at the scene of an accident, however, we couldn’t turn away. I noticed people breaking into a bar on the corner. Like an especially virulent virus, word of free liquor spread quickly and a huge crowd began to form at the bar. I then witnessed a truly amazing scene. Self-appointed bouncers soon appeared at the entrances, deciding who would be allowed to enter and who would not. When turned away, the less fortunate revealers meekly accepted their status as not being part of the “in” crowd and moved on. I watched this for more than half an hour as impromptu class divisions and a “first-come-first-stolen” hierarchy spontaneously developed. Even in the middle of a riot, society must have its rules.
It seemed like I watched my first riot for at least two hours, though it is quite possible that my sense of time was completely distorted by the strangeness of the events. I then watched how a riot ends, at least in small-town Indiana. I didn’t see them drive up, park, or get out of their cars and vans. I didn’t notice them getting into formation. I just saw as they finally approached the riotous crowd on Wabash Avenue: a neat row of 15 or 20 state police officers, each holding a snarling German Sheppard on a tight leash. They moved slowly up the street like a wall of fleshy teeth, and the crowd simply melted away. As fast as the riot started, it was over. I guess when the purpose of your mass destruction is the loss of a basketball dream, it doesn’t seem worth tangling with a vicious animal over.
So there you have it – my first riot. I too quickly left the scene when the dogs arrived. Is this how most towns deal with the loss of a major sporting event? I don’t think so. I guess Terre Haute is a special place after all.
It is funny how arbitrary numbers (usually round ones) can take on undue significance in a sport like running. When I began running half marathons, I became fixated on the goal of finishing in less than 2 hours. While the number is arbitrary (would my performance have been a failure if I’d have run the race in 2 hours and 10 seconds?), setting a goal and striving for it is an extremely valuable motivational tool that keeps me pushing and, ultimately, succeeding.
Now that half-marathon season is over, I decided to run in the Capital 10K race in Austin on March 29. But what goal to set? My first race ever was a 10K last August, and my time was a disappointing 64 minutes (granted, it was my first race and it was 95 F at the start of the race). My best 10K split during a half marathon was 55 minutes, so I decided that a goal of 50 minutes made sense. That would mean that I would have to trim my half-marathon pace of 9 minutes/mile by about 1 min/mile – not an easy task.
With the goal set, I began to train for that goal. Then, my father-in-law had to make his opinion known (something he is very good at): “You know, anyone over forty should be able to run a 10K in their age in minutes.” I was perfectly happy with my 50 minute goal, but this new challenge kept haunting me: I would need to run the race in 48:54 min (yes, I counted the days/seconds). Only about a 1 minute difference, but that can mean a lot when you are running at your limits.
So on race day, I ended up with two goals, the “official” one and the more aggressive one that I couldn’t get out of my mind. The final result? I finished the race in 49:42, for a pace of exactly 8:00 min/mile. I was very happy with the result (after all, it was a 15 minute improvement over my last 10K), though I didn’t meet the “run the race in your age” goal. Maybe next year.
Unfortunately, a personal commitment forced me to leave San Jose Thursday morning, and so I have missed what is usually one of the better days of talks and posters. Since I have nothing to report on Day 4, I’ll instead talk for a bit about the Zernike Award.
It was seven years ago that SPIE approached me with the idea of creating a major SPIE award in microlithography. I agreed to head up the effort, and gathered together a committee of other lithographers to establish the award process. Someone on the committee suggested naming the award after Frits Zernike, for three reasons. First, no major optical award had been named in his honor, even though the scientific contributions of this Nobel prize winner are legion. Second, the name has high recognition in the optical lithography community due to the ubiquitous use of the Zernike polynomial for describing lens aberrations. The third reason is more personal – Zernike’s son, Frits Zernike Jr., worked for many years in the field of lithography at Perkin-Elmer and later SVG Lithography before retiring. Some of us on the committee knew him, and when contacted he was very supportive of an award named for his father. In 2004 the first Frits Zernike Award for Microlithography was given to Burn Lin. After three years I stepped down as chair of the committee.
I’m the 6th Zernike Award winner. Which got me thinking – just which aberration is the 6th Zernike? A quick check (I looked it up in my textbook!) showed that it was 3rd order x-coma. So I decided that each Zernike winner should be named after the corresponding Zernike polynomial term. Here are the results:
Z1: Burn Lin – x-tilt
Z2: Grant Willson – y-tilt
Z3: Tim Brunner – defocus
Z4: David Williamson – astigmatism
Z5: Martin van den Brink – 45 degree astigmatism
Z6: Chris Mack – x-coma
So, if you aren’t already in a coma from 4+ days at the SPIE Advanced Lithography Symposium, it is time to start thinking about who should become Z7: y-coma.
Midweek in the conference the adrenaline of the first few days begins to wear off. Combine that with a few nights in a row with less sleep than desired and all of a sudden sitting through six papers in a row starts to seem like work. I focused on all things LER on Wednesday, trying to find the Resist Conference papers that weren’t so packed with chicken-wire diagrams and 100-letter chemical names that mere mortals might be able to understand them. I think I’m making the same comment as last year: I’m amazed at how slow our progress is at understanding the fundamental mechanisms of line-edge roughness. There is a good chance that LER will be the ultimate limiter of lithographic resolution – why isn’t the industry putting more effort into the science of it?
In the Optical Lithography session, John Petersen’s talk on interference lithography (a topic I have worked on in the past) was well received. I agree with Bruce Smith’s comment: this technology has been too long neglected.
In the evening I skipped the DfM or MfD or f-in MD or whatever it was called panel and went straight for the hospitality suites (which were more plentiful than the previous night). The Hitachi party included a routine by the stand-up comedian Don McMillan (the power-point comedian and former chip designer). He was extremely funny, as always, and the sake was excellent. Thanks to Hitachi for being such a good host.
On Tuesday, the Optical Lithography conference begins, and with four of the five conferences going in parallel things are in full swing. Still, every time I walk into one of the cavernous meeting rooms that last year would have been standing room only and this year is more than half empty, I’m reminded of the difference that one year can make.
I began by sneaking into the Alternative Lithography conference (hoping no one would recognize me) to get on update on ASML’s EUV program. I found out that the throughput of the alpha-demo tool (of automotive junkyard fame) had been improved to 4 wafers per hour. But lest you become too excited about that speedy feat, the maximum throughput for a week was 100 wafers. When I talked a user of the tool, however, he said that last week was in fact a very good week: 42 wafers processed. But then, no one defined what was meant by a wafer. Because the flare on the tool is so bad, you have to separate the exposure fields by many millimeters to keep each field from influencing its neighbors. Thus, a “wafer” has on the order of 10 exposure fields (sometimes less) – several factors of two less than a product wafer. So how far off is the throughput of the alpha-demo tool compared to the beta tool spec?
I spent most of the day in the Optical Lithography conference. The highlights of the day were the keynote by Bruce Smith (he always gives a good talk) and the Chris Bencher paper on “gridded design rules”: how to scale SRAMs, and possibly logic, for another three or four generations using sidewall-spacer double patterning. After seeing that presentation I have become a fan of the sidewall-spacer approach – I think it will take us a long way.
My biggest complaint of the day was about session organization. After an entire session of talks by IBM on source-mask optimization, I was tired of the topic and IBM’s take on it. The Applied Materials session wasn’t as monotone (and wasn’t as long) but still was too much of one company. The conference organizers (you know who you are!) need to prevent such one-company sessions.
Tuesday night is usually a time for hospitality suite overload. Not this year. This pickings were sparse and they were soon picked over by hungry (and cheap) lithographers. I ended up spending most of the night at Gordon Biersch.
The first day of the conference was an exciting one for me. I was honored and humbled to become the 6th winner of the Frits Zernike Award for Microlithography. I’ll have more to say about this later, but there is no doubt that this moment was one of the highlights of my career.
The plenary talks were exceptional this year, especially the last two. Here are some of my favorite phrases and quotes:
Lisa Su, Freescale: “Lithography-induced complexity”
Gilad Almogy, Applied Materials: “2009 will likely be the worst year ever for our industry.”
Bernie Meyerson, IBM: “Where have all the GHz gone?”
“Atoms don’t scale.”
“Scaling is dead. Moore’s Law isn’t.”
The Albany EUV alpha-demo tool “looks like you rolled an electromagnet through an automotive junkyard.”
When the conference sessions began, I attended the resist conference. It was great to witness the presentation of the first Jeff Byers Best Poster Award. I am extremely gratified to see Jeff’s memory honored in this way, though I’m sure Jeff would have shook his head in disbelief at the mere thought of such a thing! Thanks to the resist conference organizers for creating this wonderful award. At the end of the first session, just before lunch, Cliff Henderson inserted into his talk a 70th birthday recognition for Grant Willson, including beautiful collage picture of Grant and ending with a rousingly off-key rendition of the Happy Birthday song. Congratulations Grant! It’s fun to see you embarrassed.
The afternoon papers did not generate much excitement for me, and I guess I am so used to it now that I didn’t even get riled up when I saw the graphs with no numbers on the axes or the study that compared “material A” to “material B” and found, amazingly, that material A was better.
In the evening, I stood by my two posters for two and a half hours – tiring but fun. The good thing about the low attendance is that the poster session was actually manageable this year – the crowds were not so great and one could easily navigate through the isles and see the posters. Not that I did. The disadvantage of giving a poster is that you don’t get to see any of the others. Still, I had many great discussions with people who came by.
The day ended with dinner (and beer) at Gordon Biersch. A day in heaven for a lithographer.
It’s that time of year again – time to be back in San Jose for the 33rd annual SPIE Advanced Lithography Symposium. Looking back, I realize that this is the 25th consecutive Advanced Lithography (formerly Microlithography) Symposium that I have been to. That’s a lot of years! The conference has sure changed since those early days, most spectacularly in the growth of papers and attendees. In that sense, this year’s conference is harking back to a bygone era – attendance is expected to be down more than 50% from last year (due mostly to company travel restrictions). I suppose, though, that it is not fair to make such a comparison, since the number of papers is down only slightly from last year (barring an unexpected jump in the number of cancelations). It will still be impossible to see every presentation and poster that I would like!
The earliest indicator of a slow year came today, Sunday, during the short courses. Five courses were canceled and the rest had very low attendance numbers – my course drew 11 students, down from my average of 20 – 30. Still, it was a good group of students and teaching my “world according to NILS” class was fun as always.
The outlook for our industry is bleak, and yet I’m selfishly excited about this year’s symposium. I’ve been working on a fundamental understanding of line edge roughness, creating a complete stochastic model for lithography. I’ve made a lot of progress lately and I’m really looking forward to my two poster papers Monday night – some of my best work ever, I think. Let the conference begin!
Yesterday I ran in the Austin 3M Half Marathon and set a personal record (not hard to do considering this was only my second race). My time for the 13.1 miles was 1:56:25 (h:m:s – and yes, I worry about the seconds), for a pace of 8:53 per mile. My goal was to beat 9 minutes per mile, so I’m happy with the result. I’m also happy to say that the morning after the second race is not nearly as painful as the morning after the first race was. Thanks to Dave Gerold for cheering me on at mile ten as I ran through his neighborhood.