Vertical bird's beak formation leads to the injection of silicon interstitials and to compressive stress int eh silicon. Initial stages of nanometersized dislocations and stacking faults which may act as sources for further dislocation generation as well as lattice distortions were observed by highresolution transmission electron microscopy. High-dose source/drain as well as low-dose well implantations are described which lead to the generation of stacking faults which are responsible for retention time fails in dynamic random access memories. Considerations of the point defect density generated by the implantation may solve the problems. Non-optimized reactive ion etching of isolation trenches for silicon on insulator technology causes mechanical stress, defect formation and eventually metal contam ination. With help of electrical measurements using a gated-diode built into the test structure the technology could be characterized and optimized.
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