Figure 1

Schematics of the p–i–n -structures. Stacks of five layers of Ge hut clusters (quantum dots) separated by Si barriers are built in the intrinsic domains of the p–i–n diodes; the p–i–n mesa structures were formed on CZ n-Si(100) substrates (ρ=0.1 Ω cm); composition and thickness of each layer of the mesa structures as well as locations of Al contacts are shown in the scatches; (a) in the R 163 structure, the boron concentration in the Si cap layer is ∼5×10¹⁸ cm⁻³; (b) the boron concentration in the Si cap layer of the R 166 structure is ∼10¹⁹ cm⁻³.