3 mm TEM grids with 1 um holes in a 25 nm gold membrane supported by a 300-mesh grid of 10-15 um thick gold bars. The all-gold grid minimizes charging and drift, which can be especially important for cryo-EM applications.
Each grid square has 9 alignment marks, which are visible both by optical microscope and electron microscope, and have been designed with cryo-CLEM in mind. (CLEM = correlated light and electron microscopy.) These marks can be used to orient and align images to quickly find regions of interest. Additionally, each grid square has a unique set of coordinate markers indicating where in the grid it is located.
Each grid square also has an amorphous region in the central hole for Thon-ring-based calibrations, and the central grid square also has a single 10 um hole, through which a gain reference can be taken, as well as additional holes with amorphous films.
