Flat band potential metal deposit

Si(lll) plane [300]. Because the redox potential of the Cd +/Cd couple is much lower than the flat band potential of Si substrate, the surface electron concentration is sufficiently high. Thus the process occurs similarly as on a metal surface at relatively low cathodic overpotentials. The initial stages of Cd deposition were explained by progressive nucleation and cluster growth controlled by hemispherical diffusion. CdTe deposition on Si was also studied due to interest in application in IR radiation detectors. Mechanisms of this process on different planes of n-Si(lOO) was also discussed ([203, 301, 302] and references given therein). 

The potential range where gold deposition and hydrogen evolution take place is negative with respect to the flat band potential, hence, the silicon is expected to be in accumulation and the electron density at the surface is higher than in the bulk. Note that the surface electron concentration in this case is still several orders of magnitude lower than at metal surfaces, which may have a significant effect on the deposition characteristics. 

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