Final answer:
The process is called freeze-etching, a sample preparation method for SEM imaging, where metal and carbon layers are deposited to visualize specimen surfaces.
Step-by-step explanation:
The process described in the question is known as freeze-etching or freeze-etching. In this process, samples are prepared for examination, usually through a Scanning Electron Microscope (SEM). A sample is first fractured, often at cryogenic temperatures, to reveal its internal structures. Then, a heavy metal layer is deposited at an angle to shadow the exposed surfaces, providing contrast and highlighting topographical features.
Next, a uniform carbon layer is deposited from above to create a solid layer that cements the metal patches, preserving the three-dimensional structure of the specimen. This prepares the sample for electron microscopy by making it conductive and preventing charging under the electron beam, thus allowing for high-resolution imaging of surfaces and structures.