Stacking Fault Energy in Silicon

In hexagonal networks in the (111) plane of silicon both families of nodes are ``extended.'' This implies that intrinsic as well as extrinsic stacking faults have small energy. The two stacking fault energies are ∼50 ergs/cm2 and ∼60 ergs/cm2. It is not possible at present to decide which energy belongs to which stacking fault. Both the etch pits, and the dislocations on which they are centered, can be revealed in the electron microscope.