What device is used to create thin sections of specimens for electron microscopy?

An ultramicrotome is used to create thin sections of specimens for electron microscopy. This device consists of a sharp knife made of glass or diamond and a trough filled with distilled water. The knife is capable of cutting samples into ultra-thin slices of 100 nm thickness or even thinner. The cut sections are collected in the trough of water. From there they are moved to a copper grid to be studied under an electron microscope. The thin, semi-transparent cross-sections allow electrons to pass through the sample more easily. To make the samples easier to cut, they are first fixed, dehydrated, and embedded in hard resin.