The origin of extended dislocations induced by high-dose ion implantation
The origin and the generation mechanism of ion implantation-induced dislocations is investigated with an Si/sub 3/N/sub 4/ band line/space pattern. The Si/sub 3/N/sub 4/ film-edge stress not only causes dislocation propagation but also causes the formation and deformation of extended dislocations at the initial stage of annealing. The behavior is clarified that the dislocation loops are deformed into pattern-edge dislocation half loops, which accumulate at the film edge and are punched out from the edge.
MOSFET design of 100 nm node low standby power CMOS technology compatible with embedded trench DRAM and analog devices
Demonstrates an optimum design of low leakage 85nm gate CMOSFET (I/sub off//spl les/3pA//spl mu/m) for 100nm technology node. Gate dielectric module has been optimized to achieve low gate leakage, low flicker noise and sufficiently high driving current. Deep source/drain design is strongly restricted from controlling junction leakage current when integration of trench DRAM cell is considered. Especially, for nMOSFET, deep junction is formed only by using phosphorus to suppress defect creation. Short channel immunity and suppression of gate depletion are achieved simultaneously by introducing gate pre-doping technique. In addition, channel and halo profiles are optimized to reduce band-to-band tunneling (BTBT) current. As a result, we have achieved excellent performance of /spl Sigma/CV/I(=CV/I/sub dn/+CV/I/sub dp/)=10.8psec with I/sub off/=3pA//spl mu/m at V/sub dd/ of 1.2V.
Neutron Residual Stress Measurements on Rail Sections for Different Production Conditions
Rail sectioning with subsequent neutron diffraction experiments has been used to assess residual stresses in the rails. In this study we present the results of neutron stress measurements performed at the NIST Center for Neutron Research (NCNR) on rail sections from rails that were produced under various conditions. Specifically, these are air-cooled, air-cooled and roller-straightened, head-hardened and head-hardened and roller-straightened. More significantly, a head-hardened and roller-straightened rail was also studied after service to elucidate evolution of the service-induced residual stresses. In the latter case both a transverse-cut slice and the central region of a 0.53 m long piece were studied. Measurements on this piece are the first in which triaxial stresses have been determined for an intact rail. Neutron strain measurements with 3×3×3 mm3 spatial resolution were successfully employed for transversally cut slices to verify the difference in the stress state depending on the production process. Although examination of slices allows determination of only two-dimensional stresses in the plane of the slice, additional measurements on obliquely-cut slices, which were also carried out, and utilization of FEM gives the possibility of reconstructing the full triaxial stress distribution. Together, these approaches provide a better understanding of rail fabrication and the possibility of improving the durability and safety of rails in the future.Copyright © 2004 by ASME