Fig 4From: Effect of the Niobium-Doped Titanium Oxide Thickness and Thermal Oxide Layer for Silicon Quantum Dot Solar Cells as a Dopant-Blocking LayerDepth profile of phosphorus atoms in a Si-QDML/n++-poly-Si and Si-QDML/TiOx:Nb/n++-poly-Si structure using b 2-nm-thick TiOx:Nb and c 10-nm-thick TiOx:NbBack to article page