Dopant dosage

The use of SIMS to obtain quantitative information has traditionally been recognized as a very difficult task complicated by the fact that internal standards and sensitivity factors cannot be applied universally. One approach, which has met with some success in dynamic SIMS, is the construction of a depth profile of implanted dopant (of known total dopant dosage) and then to relate the integrated area under the depth profile curve to the total concentration of dopant. This allows determination of concentration at any... 

In our day-to-day profiling at SSM, we depend primarily on comparisons with theory (as In Figure 7), or on comparisons between the known Ion Implant dosage and a dosage calculated by Integrating the dopant profile. For example. In Figure 8, the known Implant fluence was 2 x 10 cm 2 while the dosage calculated from the carrier concentration profile was 1.5 x 10 cm . we also frequently compare the measured sheet resistance of a layer with a Pg value calculated from the measured resistivity profile. 

Fig. 3.17 Relation between UV dosage and order parameter of the dye dopant.

Among the techniques that can be used to introduce well defined concentrations of impurities into semiconductors, ion implantation turns out to possess particularly attractive properties. It is not dependent on the diliiisivity nor the solubility of the dopant atom in the semiconductor host, the substrate does not have to be heated as in a diffusion process, the dosage and the depth distribution of the impurity can be well controlled. On the other hand, in those first years around 1960 when the... 

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