by Ken Rygler, Rygler & Assoc. and Molecular Imprints
The halls were quiet at the SPIE Advanced Lithography Conference — you could roll a bowling ball down the exhibit aisles and not strike a soul. Having attended SEMI’s ITPC in November and SEMI’s ISS/SMC, I anticipated a dropoff in attendance. Nevertheless, I was surprised at its depth, considering SPIE is the premiere global technical lithography conference. Of course, as our industry has shifted so dramatically to Asia over the past two decades, the cost in time and money for Asian attendees was clearly not bearable to most Asian company management. Even dinner provided a litmus test — I walked across the street with no reservation and not only was there no wait, but it was more than half empty.
There was little real hard news at SPIE, besides the attendance (or lack of it). We learned SPIE is considering splitting the Alternative Lithography Technologies Conference into two conferences: EUV and “all others”. Motivation seems twofold — EUV papers continue to increase, while SPIE is looking to “all others” as a means to draw in more applications, such as hard disk drives, flat-panels, solar, biotech, and perhaps others. These seem to be reasonable goals, but what about the cost?
The industry has made a huge investment in EUV, and a number of careers have been invested in it as well. Its history has been checkered, and that is being gracious: two steps forward and one step back, with the net effect of delaying market entry for many years (some would say too many years). Renaming “SXPL” (soft x-ray projection lithography) to the more marketable “EUV” did not change the wavelength, or the fact that it is X-ray lithography which has always been fraught with a daunting list of challenges, any one of which can keep a number of engineers, scientists, academics, and students busy for years. An endless flow of papers is assured; commercial success clearly is not.
“All other” lithography technologies already have, and will continue to, draw new applications into SPIE’s predominantly semiconductor lithography conference. For example, the hard disk industry has always been involved, given their optical patterning of thin-film read/write heads. Hard disks are now moving to patterned media, and will deploy imprint technology to pattern over one billion disks, beginning soon. This is more than the global consumption of 8-inch equivalent silicon wafers. Attendance by members of the hard disk industry has increased as a consequence, as has their submission of papers.
SPIE’s challenge is balancing the needs of their largest audience: semiconductor lithographers, especially managers and directors, facing serious lithography alternatives. Recently, imprint has emerged as a serious challenger to EUV, particularly in the high-volume, fast-growing non-volatile memory market, currently dominated by NAND flash. While two alpha EUV tools have been sold to IMPLSE and IMEC, two step-and-flash imprint lithography (S-FIL) beta tools have been sold to Toshiba and SEMATECH. Recent cost-of-ownership data has given imprint a significant edge vs. both EUV and optical double patterning. In addition, e-beam direct write (aka ML2, aka maskless) is enjoying somewhat of a renaissance, thanks to at least one foundry promoting its use in small wafer runs, one of their staples. If SPIE does indeed split the current Alternative Lithography Technology Conference into two conferences, SPIE must manage it in a way that lithography managers will not be faced with impossible choices when scheduling their time.
Ken Rygler is president of Rygler & Associates Inc. and chief marketing officer of Molecular Imprints Inc.