Smaller seems to be the trend in laboratories today. Because many laboratories are scrambling for space, or have become cramped due to large instrumentation, microscopes are getting smaller and more complex, being taken to the benchtop. While for years optical microscopes reigned as the laboratory standard in microscopy, benchtop SEMs are now being considered “the next level up in microscopy,” says Dave Edwards, applications scientist for Tungsten SEM at
JEOL, Peabody, Mass.
Over the years, “researchers and developers realized they could no longer rely exclusively on optical microscopes for inspecting and evaluating materials,” says Jim Rynne, vice president of business development at Novelx, Lafayette, Calif. In a typical optical microscope, researchers could for the most part image features in the micrometer range, which, according to Rynne, “limited researchers since they could not image the most exciting and innovative technologies occurring in the nano-scale range.” And, with the advances being made within the field of nanotechnology and the drive towards smaller length scales that can span across industries, Novelx developed its mySEM, a benchtop SEM with “sub-10-nm resolution, a small footprint, and low power consumption (that of about three light bulbs),” says Rynne.
The mySEM “provides the same topographic and spatial information about surfaces as a conventional high-performance SEM,” says Rynne, and is compact compared to typical SEMs. While the typical full lab SEM is about the size of a refrigerator, and usually requires its own room due its size and the amount of dedicated facilities it needs, Novelx created the mySEM to fit into a box the size of a laser printer. Novelx also created the mySEM to install easily into a lab with a single connection to a secure power outlet, lowering the power consumption and allowing the user to be close to the technology at all times.
In order to fit the mySEM into the laser printer-sized dimensions, “Novelx leveraged silicon processing techniques to build the core technology inside the mySEM,” states Rynne. Novelx’s patented Stacked Silicon Technology is done wafer-scale on 150-mm substrates, where the company uses stacks of silicon on insulator to form the lens, apertures, and deflectors needed in the electron beam column. The silicon chip that drives the microscope is shrunk to about 10 mm on a side through this process, compared to the core technology of a full lab SEM that is about 3 feet high.
With the shrinking of the core technology, leading to the mySEM’s compact nature, “[Novelx] is distributing nanoscale imaging capabilities closer to where people are actually doing work in their labs,” says Rynne. Novelx’s objective for the mySEM was to make it like today’s PCs, where the user can do everything right in their laps.
Filling the gap between the light optical microscope and the traditional scanning electron microscope, the NeoScope, developed by JEOL and represented by
Nikon Instruments, was created as an economical, easy-to-use benchtop SEM, with an expanded depth of field compared to conventional optical scopes. Since many users of optical scopes have never used electron scopes, the NeoScope was designed with the user in mind.
Whereas in optical microscopy users “could get 1,000, maybe 1,500, at a stretch, in magnification, the NeoScope offers 20,000 in magnification,” claims Edwards. The NeoScope also offers a depth-of-field that would allow users to visualize a whole object that could expand to 2, 3, or 4 mm, and a resolution of 25 nm. However, it is the software that comes along with the instrument that promotes user-friendliness.
The NeoScope’s software is quite different from current full lab SEM software in that JEOL “wanted to set it up as if the user was standing behind a pocket digital camera,” says Edwards. Even the appearance of the user interface is that of a back side of a digital camera, which makes the software virtually familiar to any user of the NeoScope that has used a digital pocket camera.
Like the mySEM, the NeoScope earns its benchtop label because JEOL was able to take a cabinet about five feet tall and about three feet wide and shrink the electronics and electron optical components down to a single 20” box. “This speaks to electronics miniaturization and the machining of lenses and coils,” says Edwards. The NeoScope column is less than a foot in length.
While the benchtop SEM microscope market is still “in its infancy,” according to Edwards, the trends within this market are beginning to develop. While JEOL is seeing more requests from customers to “supply add ons to [their] NeoScope product,” says Edwards; Novelx is seeing a push for more benchtop products like the mySEM that can image at a nano-scale level. However, both companies agree, that the benchtop SEM market is growing, allowing SEMs to move to the next level of microscopy.
Published in R & D magazine: Vol. 51, No. 7, December, 2009, pp.22-23.
