Fabrication and study of $p$–$n$ structures with crystalline inclusions in the space-charge region

A new model of connecting elements for monolithic multijunction solar cells based on III–V compounds is proposed, in which $p$–$n$ junctions with crystalline inclusions of a foreign semiconductor material in the space-charge region are used instead of $p^{++}$–$n^{++}$ tunnel junctions. The study shows that the introduction of crystalline inclusions to the space-charge region of the $p$–$n$ junction in a GaSb-based structure allows current densities of $\sim$ 50 A/cm$^2$ at an ohmic loss of $\sim$ 0.01 $\Omega$ cm$^2$. The obtained characteristics of the connecting elements with crystalline inclusions show their applicability to multijunction solar cells for concentrated light conversion.