Measurement of the displacement field of dislocations to 0.03 A by electron microscopy.

Defects and their associated long-range strain fields are of considerable importance in many areas of materials science. For example, a major challenge facing the semiconductor industry is to understand the influence of defects on device operation, a task made difficult by the fact that their interactions with charge carriers can occur far from defect cores, where the influence of the defect is subtle and difficult to quantify. The accurate measurement of strain around defects would therefore allow more detailed understanding of how strain fields affect small structures-in particular their electronic, mechanical and chemical properties--and how such fields are modified when confined to nanometre-sized volumes.

Early stages of carbon segregation and precipitation in a sigma = 5 (310)[001] molybdenum tilt boundary.

A [Sigma] = 5 (310)[001] tilt grain boundary in molybdenum has been annealed at high temperature in the presence of carbon and observed in high-resolution electron microscopy. The carbon is located at the grain boundary in a 1-nm slab. Two different morphologies coexist.