- Using a scanning electron microscope, scientists construct the world’s smallest microhouse.
- It’s nearly 20 micrometers long, built on a cleaved optical fiber.
- The experiment was a fun way to demonstrate the accuracy and flexibility of µRobotex.
Working at nanoscale is an extremely difficult task. It involves a lot of complex materials, assembly techniques, and robotic designs to develop micro-origami structures.
Now scientists at the Femto-ST Institute, France, have developed a new way to work at such small scale. They used a dual beam scanning electron microscope (SEM)/ focused ion beam (FIB) with 6 degree-of-freedom robot to fabricate the world’s smallest microhouse.
They realized, for the first time, patterning and assembly with a preciseness of less than 2 nanometers, which could be beneficial for future robotics and optical applications.
How Did They Built This?
They combined the nano-assembling components within a vacuum chamber, and arranged an electron microscope to observe the overall process. It’s much similar to building a big dice from a piece of paper, but requires sophisticated tools and techniques.
Patterning, self-folding and installation of microhouse
Researchers used FIB [like scissor] to cut and shape the silica membrane [paper] of the house. After folding the walls into their desired locations, they used FIB’s gas injection system [at low power configurations] to fix the structure’s edges.
To demonstrate the flexibility and accuracy of the system, they gently sputtered a tiled pattern on the structure’s roof. In this overall home-building process, the system had to focus on a tiny area of 300*300 micrometer to fire ions onto silica membrane.
Courtesy of researchers | Femto-ST Institute
To do this, 2 engineers operated the robot through multiple computers. Although, some steps were already automated, the researchers hope to automate the complete assembly process in the future.
Reference: Journal of Vacuum Science & Technology | doi: 10.1116/1.5020128
Why Did They Do This?
The experiment was a fun way to demonstrate the working [flexibility and accuracy] of µRobotex – a platform to characterize and micro-assemble tiny structures whose dimensions are less than 10 micrometers. Its objective is to provide scientists in micro and nano technologies with advanced, competitive equipment at the international level.
With the help of μRobotex system, engineers can construct functionalized microstructures to identify particular molecules by placing their own microstructures onto optical fibers. These fibers would then be inserted into inaccessible or difficult-to-access regions, such as blood vessels to detect target molecules.
Furthermore, the experimental outcomes show that integrating micro-robot with SEM vacuum chamber offers the means to expand the scope of clean room facilities to construct three dimensional microstructures with different materials.
Researchers also proposed a new mechanism to manufacture several types of optical functions for trapping light, based on nano-photonic crystal, lattice, antennas, carbon nanotubes, 3-D biosensors with origami, etc.
Currently, the scientists are working to further enhance the system; They want to build tinnier structures and fix them onto carbon nanotubes, as small as 10 nanometers in radius.