Crystal defects analysis using nano-probe technologies
With the device size shrinking to deep sub-micron region, silicon crystal defects become critical to device parameters. It also brings FA (Failure Analysis) great challenges on timely and exactly identifying the defect by EFA (Electrical Failure Analysis) and PFA (Physical Failure Analysis) methods. In this paper, we report the FA's on the single bit failure of a 6T-SRAM using nano-probe technologies for electrical localization. PFA methods, such as SEM (Scanning Electron Microscope), TEM (Transmission Electron Microscope), and chemical etching were performed for failure visualization.
Case study on asymmetric Id measured on MOSFET
With the development of technological process, many Front End Of Line (FEOL) defects are found, and many studies focus on abnormal Id behavior of MOSFETs on SRAM cells. But in this paper a method of how to analyze asymmetric Id measured on a single MOSFET to locate the FEOL defect based on real case analysis is introduced. With studies on cases with asymmetric Id, we have built the corresponding failure mechanism and summarized a decision tree in order to analyze that kind of cases. The decision tree and thinking method are also applied in other cases analysis and shown to be effective.
Archaeology and mud wall decay in a West African village
Abstract A detailed study of the processes of deterioration of mud walls and of the physical evolution and devolution of a contemporary West African village is seen to facilitate the location of decayed mud structures at a nearby archaeological site. Various climatic and pedological conditions at the site make it unlikely that such walls will be discerned. The archaeologist wishing to obtain the fullest and least biased picture of the settlement configuration of the ancient community should therefore heed all the inferential lessons to be had from a focused ethnographic investigation. Given similar climatic situations and practices of house construction, taphonomy and ethnographic analogies may both be necessary for a valid reconstruction of an archaeological settlement.