Capacitive coupling devices and methods of fabricating a capacitive coupling device are disclosed. The coupling device could include a stack of layers forming electrodes and at least one insulator. The insulator could include a region of doped silicon. The silicon could be doped with a species selected from Ce, Cr, Co, Cu, Dy, Er, Eu, Ho, Ir, Li, Lu, Mn, Pr, Rb, Sm, Sr, Tb, Tm, Yb, Y, Ac, Am, Ba, Be, Cd, Gd, Fe, La, Pb, Ni, Ra, Sc, Th, Hf, Tl, Sn, Np, Rh, U, Zn, Ag, and Yb in relief and forming roughnesses relative to the neighboring regions of the same level in the stack. The electrodes and the insulator form conformal layers above the doped silicon region.