Dissociative chemisorption of O2 inducing stress corrosion cracking in silicon crystals.
Fracture experiments to evaluate the cleavage energy of the (110)[1 1 0] and (111)[1 1 2] cleavage systems in silicon at room temperature and humidity give 2.7 ± 0.3 and 2.2 ± 0.2 J/m(2), respectively, lower than any previous measurement and inconsistent with density functional theory (DFT) surface energy calculations of 3.46 and 2.88 J/m(2). However, in an inert gas environment, we measure values of 3.5 ± 0.2 and 2.9 ± 0.2 J/m(2), consistent with DFT, that suggest a previously undetected stress corrosion cracking scenario for Si crack initiation in room conditions. This is fully confirmed by hybrid quantum-mechanics-molecular-mechanics calculations.
Department of Materials Science and Engineering, Technion, Haifa 32000, Israel.
Anna
A
Gleizer
Department of Physics, King's College London, Strand, London WC2R 2LS, United Kingdom.
Giovanni
G
Peralta
Department of Physics, King's College London, Strand, London WC2R 2LS, United Kingdom.
James R
JR
Kermode
Department of Physics, King's College London, Strand, London WC2R 2LS, United Kingdom and CENMAT-UTS, Via Alfonso Valerio 2, 34127 Trieste, Italy.
Alessandro
A
De Vita
Department of Materials Science and Engineering, Technion, Haifa 32000, Israel.
Dov
D
Sherman
D000327:Adsorption; D003343:Corrosion; D008956:Models, Chemical; D010100:Oxygen / Q000737:chemistry*; D011789:Quantum Theory; D012825:Silicon / Q000737:chemistry*; D013816:Thermodynamics
D010100:Oxygen; D012825:Silicon