The largest change in DAWIA STM
certification in recent years is in the training requirements, with two of the three required STM
courses new for Fiscal Year (FY) 2016.
To release the cargo, the scientists use the STM
tip to lift the HB-HBP molecule.
In general, these STM
manipulations must take place at extremely low temperatures to keep the reactant molecules from randomly hopping around.
Because the STM
can depict only electrically conducting surfaces, its ability to investigate many materials, such as biological samples, is limited.
To pull atoms out of a silicon surface where they are covalently bonded, Avouris and Lyo tap chemical forces that come into play when the STM
tip nears the surface.
Looking at HOPG under an STM
is "like looking at a marble floor in a bathroom: You can see anything you want to in it," Lindsay notes.
Last April, for instance, another IBM team reported it had written "IBM" by pushing individual xenon atoms into place with an STM
, but this required supercold temperatures and a vacuum.
In another, they "corralled" molecules by encircling them with a computer-controlled STM