Projection Electron Beam Lithography Breakthrough
Achieved by Bell Laboratories Researchers
biz.yahoo.com
MURRAY HILL, N.J.--(BUSINESS WIRE)--Nov. 5, 1997--Researchers at Bell Laboratories, the
R&D arm of Lucent Technologies, reached a new milestone in developing projection electron beam
lithography to produce smaller, more powerful integrated circuits.
Using their SCALPEL(TM) system, researchers scanned a pattern mask to print a stripe of features on
a wafer, then shifted the mask and wafer to print another stripe immediately next to and in precise
alignment with the previous one. By printing four adjacent stacks of 100 stripes, the researchers
produced a one-centimeter-square field of semiconductor features.
''This is the first time anyone has demonstrated 'step-and-scan' lithography using electron beams,''
said Lloyd Harriott, head of the Advanced Lithography Research Department at Bell Labs. ''This is
the breakthrough we needed to prove that projection electron beam technology can print chips. It's a
key step toward developing the technology for commercial semiconductor production.''
The SCALPEL effort, supported in part by DARPA and SEMATECH, represents one of a handful of
techniques that semiconductor industry members are investigating as an eventual replacement for
optical lithography, which today produces features as small as 0.25 microns. While optical techniques
are expected to support another two or so generations of miniaturization (0.18 and 0.13 microns),
techniques using shorter-wavelength radiation sources will be needed to continue doubling the
number of components on a chip every few years through the end of the next decade.
''Bell Labs made fundamental contributions to all the techniques being investigated today,'' said
Harriott. ''But we believe the projection electron beam technique can be developed more quickly and
economically than the others. This latest achievement reinforces our belief.''
Bell Labs began development work on the current SCALPEL system in 1994, and printed its first
0.08 micron features in June of 1996. Harriott refers to that achievement as the ''proof of concept'' for
projection electron beam technology.
''Now, a little more than one year later, we have demonstrated what I call 'proof of lithography,''' said
Harriott. ''If we can produce a centimeter-square field, we know we can do more. In the coming
months, we will work to increase the field size and our throughput speed.''
Harriott noted that the stripes produced in this demonstration are aligned with each other to an
accuracy of at least 0.05 microns, or 50 nanometers.
''Our goal is to achieve alignments within 10 nanometers,'' he said. ''We know we're better than 50
nanometers right now, but we need more accurate markers to know how much better.''
Lucent Technologies, headquartered in Murray Hill, N.J., designs, builds and delivers a wide range of
public and private networks, communications systems and software, data networking systems,
business telephone systems and microelectronic components. Bell Labs is the research and
development arm for the company. For more information on Lucent Technologies, visit our web site
at lucent.com. The SCALPEL project web site is at lucent.com |
