Doping agents

In order to detect possible impurities or doping agents at rather low concentrations the SIMS method should be chosen. Compared to XPS the detection limit of SIMS is... 

Colorless gas with a mild odor described as fishy or like garlic. It is detectable at 0.5 ppm. Used as a doping agent for solid-state electronic components, in the preparation of gallium arsenide and glass dyes, and in the manufacture of light-emitting diodes. 

Used industrially as a fumigant, doping agent for semiconductors, and intermediate for preparation of some flame retardants. 

Uses. In metallurgy for hardening copper and lead alloys to prepare GaAs for electronic devices, doping agent in germanium and silicon solid state products, special solders. 

Kintz P, Samyn N. 2002. Use of alternative specimens drugs of abuse in saliva and doping agents in hair. Ther Drug Monit 24 239. 

Segura J, Ventura R, Jurado C. 1998. Derivatization procedures for gas chromatographic determination of xenobio-tics in biological samples, with special attention to drugs of abuse and doping agents. J Chromatogr B 713 61. 

Uses. Doping agent for solid-state electronic components... 

Uses. Insecticide used for fumigation preparation of phosphonium halides doping agent in semiconductor manufacture... 

Arsine is used as a reducing agent and to synthesize many organoarsine derivatives. It is also used as a doping agent for solid state electronic components. Earlier, it was used as a military poison gas. It does not occur freely in nature but is susceptible to form upon contact of arsenic compounds with acid in presence of a metal. Thus commercial acids stored in metal tanks and contaminated with arsenic impurities may produce arsine. 

The conductivity of polyacetylene can be magnified by doping. Exposure of a polyacetylene film to dry ammonia gas leads to a dramatic increase in conductivity of 10 cm) Controlled addition of an acceptor, or /r-doping, agent such as AsFs, I2,... 

The addition of doping agents can increase the photoconductivity of dyes by several orders of magnitude 52,74), Some examples are given in Table 7. 

Like dark conductivity, photoconductivity increases rapidly with the concentration of the doping compound [see Eq. (51)]. Suitable doping agents can give photoconductive gains G > 1 52>. 

Tremblay, P., Groleau, P. E., Ayotte, C., Picard, P., and Viel, E. (2008). High-throughput screening and quantification of doping agents in urine using LDTD-APCI-MS/MS. In... 

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