Trap and Dislocation Electrical Activity in a Reversely Biased P-N Junction in Silicon

Defects Due to Metal Silicide Precipitation in Microelectronic Device Manufacturing: The Unlovely Face of Transition Metal Silicides

“…Due to their harmful effects on device properties they are a subject of research and dispute from the very beginning. Furthermore, some detailed investigations have been carried out on real devices, such as DRAMs, in which for specific defects the physical effects leading to device failures, in particular retention time fails, have been elucidated [44]. Over the years the situation has changed fortunately.…”

“…In reverse biased junctions and capacitor space charge regions, the electrical activity of defects associated with deep localized or band-like states is only due to carrier emission, stimulated by the local electric field function of the defect location and of the applied reverse voltage through Poole-Frenkel and Fowler-Nordheim mechanisms [44]. In DRAMs, whose memory cells consist of a storage capacitor and a transfer transistor (switch), in addition a space charge region at the capacitor extended into the silicon substrate in former cell concepts, such as the DRAM with trench capacitor (discussed in Section 2.1) which contained defective memory cells due to Cu-silicide precipitates.…”

“…The electrical activity of the silicide precipitates can be interpreted according to mechanisms recently described by Schro È ter and coworkers [41±43] and Leroy [44]. However, certain metals like Fe, Ni and Cu, which are ubiquitous in the technical environment, entering inadver-Defects Due to Metal Silicide Precipitation in Microelectronic Device Manufacturing tently into the silicon substrates during device manufacturing processes can act as major yield detractor and may give rise to device reliability problems.…”