Fig 1.
Experimental overview of the Laplace Project.
The ultrahigh vacuum carry transfer suitcase (UHVCTS—top left) can be securely fastened to every experimental platform via an ultrahigh vacuum loadlock (top right) which is pumped as necessary to maintain conditions in either microscope or glovebox. It is planned to mount the suitcase upon future instruments. Schematics detailing the basic configuration of the transfer are detailed for each platform (below).
Fig 2.
(a) A side-view of the cryogenic ultrahigh vacuum transfer into the buffer chamber of the local electrode atom probe (LEAP 5000XR). The connection is made at the labelled CF40 flange. (b) An expanded view of the interlocking pieces used to transfer cryogenically-cooled samples from the suitcase to the atom probe’s analysis stage with no increase in temperature. (CF40: ConFlat 40 mm flange; UHV: ultrahigh vacuum; CTS: carry transfer suitcase; PEEK: polyether ether ketone).
Fig 3.
Xenon plasma focussed ion beam microscope modifications.
(a) The configuration of the solid-state cooling bands in the scanning electron microscope (SEM) chamber with PT100 resistance thermometers. (b) An aerial view of the SEM side-chamber allowing for the cryogenic sample transfer between the two different vacuum regimes of the suitcase and the SEM chamber. The connection is made at the labelled CF40 flange (ConFlat 40 mm). UHV: ultrahigh vacuum; CTS: carry transfer suitcase.
Fig 4.
Preparation and ultrahigh vacuum transfer of magnesium.
Atom probe reconstructions of pure magnesium samples prepared and transferred in the following protocols. In each of the shown reconstructions, MgO, Mg2O and O species are shown by green, red and blue dots respectively. (a) Room temperature fabrication, stored for 1 week in buffer, removed to atmosphere for 3 minutes before the atom probe. (b) Room temperature fabrication, stored for 2 weeks in buffer before atom probe. (c) Milled using the cryogenically-cooled stage, stored for 1 week in buffer before atom probe. (d) Milled using the cryogenically-cooled stage, transferred with the cryogenic ultrahigh vacuum carry transfer suitcase, and then atom probe immediately). (e) The mass-to-charge spectra of experiments (a) & (b) demonstrating that, while oxygen was definitely present, little hydrogen is detected.
Fig 5.
(a) A 36-microtip array photographed approximately 90 seconds after removal from a liquid nitrogen bath (≈ −196 °C) and evidencing significant ice condensation in a laboratory atmosphere. (b) The same 36-microtip array, 90 seconds after removal from the liquid nitrogen bath, this time showing no ice condensation while standing in the glovebox’s dry N2 atmosphere. (c) A ≈1-mm sphere of pure water ice upon a 0.3-mm stainless steel wire. (d) From the sphere, a 50-nm atom probe needle was fashioned in the plasma focussed ion beam microscope with the cold-stage and transferred to the local electrode atom probe (LEAP 5000XS) with the cryogenic ultrahigh vacuum carry transfer suitcase.