Forming a vitrified sample for electron microscopy

Abstract

The invention relates to a method of forming a vitrified sample on a sample holder for inspection in an electron microscope. It is known to spray a solution on a grid and then immerse the grid in a cryogenic liquid, such as ethane or liquid nitrogen. The invention proposes to spray small droplets of the liquid on a cryogenic surface, such as a grid or a sample holder in vacuum. The liquid forms vitrified sample material when hitting the surface due to the low temperature of the grid or sample holder. A lamella may be excavated from the thus formed sample material, to be studied in a TEM, or the vitrified sample material may be directly observed in a SEM. In an embodiment the material may be sprayed on a cryogenic liquid, to be scooped from the liquid and placed on a grid.