Researchers at IBM and Nion Co. have developed a technique to extend the capabilities of electron microscopes. The development is particularly useful for semiconductor and computer chip manufacturers, as their devices are shrinking to atomic scales.
Conventional electron microscopes use magnetic lenses to focus electrons into very small beams to image tiny features. Until recently, with the advent of nanotechnology and the push for smaller computer chips, researchers were able to work within the limitations of electron microscopes. However, these limitations, namely image blurring due to lens imperfections or ‘aberrations’ have become more of a problem.
The new technique combines seven new sets of magnetic lenses and powerful computers to correct the aberrations in real time. With these changes the electron microscopes can produce an electron beam that is only 75 thousands of a nanometer in size. This is smaller than a hydrogen atom, and the smallest electron beam to date.
These developments, recently published in the journal ‘Nature’, will allow developers of devices such as silicon chips to more accurately identify and correct defects in their atomic structure. Without them, they are only able to guess at what these defect may be as the images and information were incomplete due to the difficulty in accurately imaging them.