An apparatus for plasma cleaning and storage of transmission electron microscopy specimens and specimen holders.

Abstract

The transmission electron microscopy (TEM) specimen with thickness in nanometer scale is susceptible to hydrocarbon contamination and oxidation, and the specimen holder is also susceptible to contaminants, which would deteriorate the quality of TEM imaging and degrade the efficiency of TEM experiments. Conventional pretreatment devices often have limited functions and low practicability, which may cause problems for TEM specimens and holders. In this work, a multifunctional apparatus for plasma cleaning and storage of TEM specimens and specimen holders is developed based on the specific design of the vacuum joints. The apparatus includes a plasma cleaning system, holder storage station, and specimen storage station, which share the same vacuum system. The cleaning of hydrocarbon contaminants on the specimen and storage of the specimens and holders can be achieved simultaneously in this apparatus. TEM imaging and energy-dispersive X-ray spectroscopy (EDS) analyses of two treated specimens using the apparatus demonstrated that it could effectively remove hydrocarbon contaminants on the specimen. The holder storage station, used to preserve TEM holders in vacuum conditions, can also be modified as a specimen storage station by an appropriate design of the specimen storage platform, in which specimens are protected from water and contaminations. The designed apparatus not only robustly avoids damage to the ultrathin specimen and holders but also improves the working efficiency and reduces costs. These advantages could make our apparatus more appealing for the complement to the present commercial plasma cleaning and storage devices. HIGHLIGHTS: An apparatus for the pretreatment of transmission electron microscopy (TEM) specimens and specimen holders with three functions-plasma cleaning, holder storage, and specimen storage-was designed and fabricated. Using this single apparatus, the cleaning of hydrocarbon contaminants on the specimen and storage of the specimens and holders can be achieved simultaneously. The designed apparatus can not only robustly avoid damage to the ultrathin specimen and holders but also improve the working efficiency and reduce costs by adopting a single vacuum system. These advantages could make our apparatus more appealing for the complement to the present commercial plasma cleaning and storage devices.