The generation of process-induced dislocations around a shallow trench isolation was clarified by using convergent-beam electron diffraction. Upon comparing the resolved shear strain of 12 slip systems, it was found that, at the trench bottom corner, the resolved shear strain on slip systems (1¯11)[011] and (1¯11)[10¯1] was largest in all slip systems. In fact, the dislocations of slip systems (1¯11)[011] and (1¯11)[10¯1] were observed around the trench bottom corner more often than those of any other slip systems. It was also found that the large resolved shear strain at the trench bottom corner may be due to the corner shape or the intrinsic stress induced during oxidation. Therefore, to control dislocation around shallow trench isolation, the oxidation-induced stress at the trench bottom corner must be reduced, and the shape of the bottom corner must be controlled.

Determining the Relationship between Local Lattice Strain and Slip Systems of Dislocations around Shallow Trench Isolation by Convergent-Beam Electron Diffraction. A.Toda, N.Ikarashi, H.Ono, K.Okonogi: Applied Physics Letters, 2002, 80[13], 2278-80