Defects in Silicon Crystals Dislocations 0000000000000 00000000000 Intrinsic point defects in 00000000000 O0O000O0O000 a crystal N and N o0000o0000ooo increase with T 业 0000000000000 0000000000000 o0o0900888000oo00 oooO 00O 88808888088899008 00000O00O0000 ●●●●●●●●● Agglomeration of 0000000000000 000000000000o6008 00008000000000000 Interstitials 号 Extrinsic-type dislocation loop. 0000000009908 90980o00o9800 O000 HOOOO o088600008886 collapse 0000000000000 Sequence of intrinsic-type dislocation loop formation. One-dimensional defects (dislocations): 。 Edge dislocation,dislocation loop Macroscopic edge dislocations stress in silicon after high temperature processes (LOCOS);temperature gradients during processing Microscopic dislocation loops agglomeration of V I during a cooling process (not enough time for V&I recombination) Dislocations can move when subjected to stresses or when excess point defects are presentDefects in Silicon Crystals – Dislocations Intrinsic point defects in a crystal N v and NI increase with T Agglomeration of Interstitials collapse One-dimensional defects (dislocations): • Edge dislocation, dislocation loop • Macroscopic edge dislocations Macroscopic edge dislocations Å stress in silicon after high temperature processes stress in silicon after high temperature processes (LOCOS); temperature gradients during processing • Microscopic dislocation loops Å agglomeration of V & I during a cooling process (not enough time for V & I recombination) • Di l i h bj d h i d f islocations can move w hen subjecte d to stresses or w hen excess point d e fects are present