Medard W. Welch Award of the American Vacuum Society (1992) Ernst G. Bauer (born February 27, 1928) is a German-American physicist known for his studies in the field of surface science, thin film growth and nucleation mechanisms and the invention in 1962 of the Low Energy Electron Microscopy (LEEM).

In 1958 he moved to the Michelson Laboratory in China Lake, California, where he became the Head of the Crystal Physics Branch and a U.S. citizen.

After he moved to the Technical University Clausthal (Germany) in 1969 Bauer built up a broadly based surface science group encompassing a large variety of electron and ion beam techniques as well as optical methods.

The quantitative analysis of thermal desorption spectroscopy (TDS or TPD) was developed, a method now used widely in particular in surface chemistry.

Work function measurements were developed and used for the determination of the thermodynamic properties of two-dimensional systems with attractive lateral interactions.

His work was brought to the attention of a much wider general scientific community in the nineteen eighties, when LEEM began producing the real-time high-resolution dynamic image recordings of atomic processes such as crystal nucleation and growth, sublimation, phase transitions and epitaxy on surfaces.

The combination of these methods now allows a comprehensive (structural, chemical, magnetic and electronic) characterization of surfaces and thin films on the 10 nm scale.