Nanotechnology: views of Scientists and Engineers
Nanoengineering and Measurement
a) Definitions
The group considered the working definitions used by
the main Working Group for the study. It was decided
that the separation of “nanotechnology”
and “nanoscience” in the definition was
important. However, it was felt that the “nanotechnology”
definition was too narrow in that it incorporated “top
down” nanoengineering well but did not cover surface
treatments and structures so well and did not capture
the aspects of ultraprecision engineering, whereby objects
are defined in shape to sub-100nm precision.
There was some discussion about the length scale used
in the definition. It was felt that the definition should
include reference to the special behaviours of materials
at these length scales. It was suggested that the length
scale might be smaller, maybe 10nm and below where quantum
effects are observed, but this was countered on the
basis that novel effects are observed in machining materials
at the 100nm scale as well. The final compromise was
that the length scale, although important to be included
in the definition, was arbitrary and should be used
in conjunction with “novel bulk or quantum (physico-chemical)
effects”. It was pointed out that dimensionality
was also important from a purely economic aspect –
the shrinkage of semiconductor circuits being a particular
case in point. Here there is no paricular advantage
in terms of novel physical properties in shrinking the
dimensionality, but there are very important economic
consequences in so doing. It was also suggested that
the effects of dimensionality on health and safety issues
could be included as well as the physical properties.
b) Current State of Knowledge
One key issue identified by the group was metrology.
While Atomic Force Microscopy and Scanning Probe Microscopy
(collectively SPM) were led from ouside the UK, they
were in a good state in the UK and Europe. However,
there was a problem with repeatability of results and
standards. Round robin tests conducted by NPL had shown
huge amounts of variability. While a relative measurement
often sufficed within a lab or organisation, there was
little repeatability of results outside due to variation
in the cantilever beams and equipment. The repeatable
measurement of forces (for example in the study of bonding
between biomolecules, such as DNA, and surfaces) was
a particular case in point. It was agreed that the UK
had a leading position in the establishment of traceable
standards for the SPM and that NIST (USA) and PBT (Germany)
were also entering this field. Such standards will be
essential in moving these tools out of the science arena
and into the technology arena. It was noted that SPM
tools were already being used for manipulation as well
as observation and would be key tools in the further
development of nanoengineering.
The use of SPM as a process tool to manipulate materials
and “add value through size” in the chemical
industry was discussed. The essential nature of MEMS
(MicroElectroMechanical Systems) as a route create massively
parallel SPM’s (e.g. “Millipede”)
for such applications was noted. The group saw SPM becoming
an important process tool by around 2020 with this possibly
heralding the real commercial revolution in nanotechnology.
Particle beam and X-ray spectroscopy were mentioned
as key technologies with two out of three of the main
companies supplying equipment being based in the UK.
The area of ultra-precision engineering, whereby material
can be removed at sub-100nm precision, was noted as
an important area. For example, the whole of the semiconductor
process industry is based upon the ability to manipulate
device wafers to this level of precision and this was
based upon the ability to machine and measure components
at this level. The ability to remove material to this
level of precision was also cited as being important
in minimising sub-surface damage and improving system
reliability in a wide range of components. The UK has
a very strong position in this field.
The Group discussed what was required to make the
potential process tools of the future become economic
for the production. This discussion looked at the use
of nanoengineering in production rather than the production
of nano products per se. The consensus was that the
use of MEMS as a production technology was inevitable,
but scaling up of production was the key, for instance,
scaling up from one device to 100 or 1,000. With this
technology there was the potential to create truly green
manufacturing with no waste, no solvents and very efficient
use of materials.
c) Applications
It was noted during the discussions of the group that
the topic area they were considering was already rich
in applications (the SPM, particle beam and ultra-precision
engineering industrial sectors noted above are currently
generating many billions of dollars in revenue world-wide).
The Group also felt that MEMS/NEMS would be among the
first new applications of nanoscale engineering in the
market place. This led to some discussion around market
drivers for such devices and it was agreed that applications
for the young would be most important with China and
India becoming very important as demographic differences
between there and the West kicked in the 2020 timeframe
discussed. It was noted that in the microelectronic
industry, a key market driver had similarly been the
youth market for mobile phones and games. An example
that was discussed in the field of MEMS were shape memory
alloys, which were finding applications within toys,
specifically to make a doll that could react to sound
by moving its eyes.
Again with applications, the group considered that
market forces would be important. A combination of technology
push and market pull would be required. Another example
discussed was mobile communications in the Far East,
and China in particular, where 3G and eventually 4G
would expand rapidly. For microelectronics, it was noted
that the defence market had been a key driver in the
1980’s, but it was not felt that this would be
a significant driver for nanotechnology. However, it
was noted that the US DoD was currently a major investor
in the field.
The application of MEMS to nanomanufacturing in the
chemical industry was discussed, where there was a requirement
to produce materials with “6?” or even “9?”
reliability. Here, the ability of MEMS to be scaled-up
with the high reproducibility inherent in the electronics
industry was seen as being very important.
Another area where nanotechnology in general might
be capable of providing important applications in the
future was in the provision of clean potable water from
sea-water through the use of nanoscale filtration.
This moved discussion on to strategy. The group felt
that the UK did not have a strategic view on the development
of nanotechnology, in contrast with its major international
competitors. It was noted that the UK did organise a
number of technology missions around the world and that
much information was being brought back and disseminated,
but the strategic vision called for had still not developed.
The importance of networks was stressed with the group
feeling that the nanotechnology community is not yet
good at this. A significant lack of networking in the
commercial arena was noted. It was felt that the lack
of a research centre was a disadvantage when compared
with e.g. France where Grenoble is currently a large
and growing centre of excellence.
The group discussed the possibility that manufacturing
in the field would inevitably move to the Far East.
It was felt that although this may happen, most of the
companies involved were already truly global in their
outlook and were probably not thinking in terms of moving
manufacture to the cheapest areas in the same way as
has been seen in the past. A related issue of moving
manufacture abroad was discussed briefly; that of exporting
health and safety issues to countries less able to deal
with them.
d) Science Fiction
There was nothing in the topic area specifically assigned
to the group that could be said to be “science
fiction”. The group picked-up on Drexler’s
ideas as having been a source for the current hype about
the field; however, Gene Rodenberry and Star Trek were
also identified as other sources. The key to science
fiction scare stories becoming significant was felt
to be their sublimation into pop culture.
Questions as to what was physically possible were
discussed. It was decided that the only way to categorically
rule out any of the scare stories would be to address
the issue of their possibility based on the laws of
physics alone. The group did not feel it was possible
to do that within the context of the time available.
It was felt that it should be possible to put likely
timescales on many possible developments. The idea that
some sort of self-replicating “nanobots”
could wreak havoc was explored, but it was felt that
the complexity of such systems would mean that, even
if their construction was to be physically possible,
which was doubtful, their realisation was a very long
way in the future. The prospect of “Jules Verne”
injectable devices was felt to be very unlikely, but
single nano devices with a single simple function could
be envisaged. The issues of the hazards of artificially-created
self-replicating systems were discussed. It was suggested
that prions had already indicated that a self-replicating
particle without any intelligence could cause problems,
but that this was a biological particle and it could
only replicate when in very specific environments. This
was a far-cry from the “grey goo” hazard
that seemed to be exercising the popular mind. Some
aspects of bionanotechnology could generate concern,
especially when combined with the prospect of self-replication.
It was felt that public unease at least in part depended
on the use of language in the description of technological
developments. For example, some of the group felt that
the term “smart” could cause public concern,
being confused with artificially intelligent devices.
In summary, the group felt that the “gray goo”
scenario could only be conclusively ruled out through
careful analysis based upon the rigorous use of known
physical laws (it is probably not sufficient to simply
say “this is impossible”), but even if the
technology to create self-replicating nanobots were
to be physically possible, which many doubted, it would
not be available until the distant future, perhaps 2080
at least.
e) Other Areas
Nanomaterials were felt to be an area with fuzzy limits.
It seemed probable that most of the health and safety
issues would manifest themselves here. Problems such
as those with PM10s, which could be considered to be
similar to nanoparticles, were recognised and understood
and there seem to be potential problems with the hazards
of production, use and disposal of new materials. Health
and safety issues were discussed. Some attendees wondered
whether carbon nanotubes and nanoparticles may have
the potential to be hazardous in unpredictable ways,
but it was felt that companies had learned the lessons
associated with these hazards and that regulations existed
to prevent the uncontrolled release of hazardous materials.
A possible consideration for the working group might
be whether new regulations relating specifically to
nanoparticles were either necessary or desirable. Again,
this could only be determined through the acquisition
and application of knowledge about the systems concerned.
The group decided that the lack of a strategy for nanotechnology
discussed earlier could hold up development across the
board. It was also felt that there was a real need to
look at what could be possible in what timescales. In
order to facilitate both of these, the generation of
a road map was proposed. Road maps have been used for
a number years in the semi-conductor industry where
they have specific goals, identifying areas where new
research and development needs to be carried out to
attain them. For nanotechnology, the specific goals
and technologies could not at first be identified, but
a general road map would give the framework onto which
specific technologies and goals could be mapped.
The generality of the proposed nanotechnology road
map meant that it would be helpful to consider aspects
of technology push, consumer pull, control and regulation,
and health and safety issues. It was suggested that
such a road map could be of use to the main working
group in the present study as it would help to put some
of the prospective developments into a temporal context
and show important potential technology linkages and
potential markets. The development of a general road
map for specific targets and technologies could be a
recommendation of the study. The creation of such a
road map would need a significant amount of resource
to be allocated to it. It would also require the cooperation
of the industrial concerns in the field.
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