Direct observation of microtwin formation at crack tips in InP

Journal Article · Sat Feb 15 04:00:00 EST 1992 · Scripta Metallurgica; (United States)

DOI:https://doi.org/10.1016/0956-716X(92)90293-N· OSTI ID:5632853

Vanderschaeve, G; Caillard, D ^[1]; Peyrade, J P ^[2]

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1. Lab. de Physique des Solides, INSA, Complexe Scientifique de Rangueil, 31077 Toulouse Cedex (FR)
2. CEMES, CNRS, BP 4347, 31055 Toulouse Cedex (FR)

This paper reports that in brittle materials which contain cracks, stress concentrations arise at crack tips. At low temperatures, when the load is increased, brittle fracture happens for a critical stress intensity factor, which is an intrinsic material property, depending on the loading mode and on the cleavage plane. At higher temperatures dislocations may be emitted at the crack tip: a plastic zone is formed, which releases the stresses and increases the critical load for crack propagation. It is generally accepted that the brittle-to ductile transition is controlled directly or indirectly by dislocation mobility. During the course of an in situ transmission electron microscopy, study of dislocation mobility in the III-V compound InP, we have observed the nucleation at a crack tip and the propagation of partial dislocations of same Burgers vectors, resulting in a microtwinning of the crystal. Such an observation provides information on both the way stress relaxation occurs and the relative mobilities of the partial dislocations in this material. In spite of the importance of twin formation on the quality of the material used as substrate in semiconducting devices, this last point is rather poorly documented.

• OSTI ID: 5632853
• Journal Information: Scripta Metallurgica; (United States), Journal Name: Scripta Metallurgica; (United States) Vol. 26:4; ISSN 0036-9748; ISSN SCRMB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602* -- Other Materials-- Structure & Phase Studies
360603 -- Materials-- Properties
ARSENIC COMPOUNDS
ARSENIDES
BURGERS VECTOR
CRACK PROPAGATION
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DISLOCATIONS
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
INDIUM COMPOUNDS
INDIUM PHOSPHIDES
LINE DEFECTS
PHASE TRANSFORMATIONS
PHOSPHIDES
PHOSPHORUS COMPOUNDS
PNICTIDES
SEMICONDUCTOR DEVICES
TEMPERATURE EFFECTS