Carrier concentration profiling

AC Properties of Silicon Electrodes and Carrier Concentration Profiling... 

This section summarizes the AC behavior of a silicon electrode and introduces an application of these properties, the carrier concentration profiling technique. 

E. Peiner and A. Schlachetzki, Anodic dissolution during electrochemical carrier concentration profiling of silicon, /. Electrochem. Soc. 139, 552, 1992. 

Figure 8 Is a more recent spreading resistance and carrier concentration profile of a low dose boron lon-lmplant Into an N-type substrate. The peak In the spreading resistance profile at about 9 X 10 ohms Indicates the position of the PN junction. The...

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. 

Figure 8. Spreading resistance and carrier concentration profiles of a boron lon-lmplant Into an N-type substrate as measured with controlled low penetration, 10 gram probes ...

Spreading resistance profiles are generated quickly, so the technique Is useful when speed Is essential. Most silicon structures can be bevelled and measured and the raw data then processed and plotted as a resistivity or carrier concentration profile In less than thirty minutes. 

Figure 5. Carrier concentration profile of same Si n-p-n structure as shown in Figure 4. The profile was measured by two different labs using the spreading resistance technique. (Adapted from Ref. 1.)...

The typical C-V characteristic of the Ni/por-SiC/SiC structure and its carrier concentration profile obtained based on that measurement are shown in Figure 2.24(a) and (b), respectively. It can be seen that the carrier concentration gradually decreases from a value of 1017 cm-3... 

Carrier concentration profiles of unintentionally doped GaAs grown on Si substrates, before and after hydrogenation, are... 

Fig. 14 Carrier concentration profile of CaAs on Si with and without hydrogenation.

The excess minority carrier concentration can be viewed as an additional stationary concentration term that enters the chemical potential although this terminology is strictly only valid in equilibrium. Extending the consideration to a stationary illumination situation where an excess carrier concentration profile exists for a given minority carrier lifetime and for defined boundary conditions, the concept of quasi-Fermi levels can be introduced. Using the Boltzmann... 

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