National Institute of Standards and Technology researchers have come up with a technique that can simultaneously identify individual defects in microcircuits on the same chip.
The method, dubbed remote bias-induced electrostatic force microscopy, involves the application of specific alternating current voltages to neighboring wires instead of to the atomic force microscope’s tip, NIST said Thursday.
According to NIST, an AFM comes with an ultrasharp tip connected to a cantilever that “vibrates like a diving board.” Under the existing method, AC voltage is applied to the AFM tip as it screens across wires buried beneath the surface of a chip and a flaw in a wire will emerge marked by the change in the tip’s vibration.
With the new technique, researchers applied out-of-phase AC voltages to neighboring wires and were able to detect the flaws and produce clear images of defects in wires.
The technique was developed by NIST scientists Joseph Kopanski, Evgheni Strelcov and Lin You.
“Applying a voltage to the wires instead of the AFM tip may seem like a small innovation, but it makes a big difference,” said Kopanski.
“The method does not require a new instrument and could be easily implemented by the semiconductor industry,” he added.
