Abstract:
This letter consider arrays of vertically oriented silicon wires obtained by cryogenic dry etching of silicon substrates with a free electron density of $n$ = 10$^{16}$ and 10$^{17}$ cm$^{-3}$, a height of 6 $\mu$m, and a diameter of 1.7 and 1.2 $\mu$m, respectively. It is shown that gold sputtering makes it possible to form a Schottky diode with an ideality factor of 1.1 – 1.3 and a barrier height of 0.6 – 0.7 eV relative to the given parameters of these arrays. It is shown that the experimental capacitance–voltage characteristics of such structures can be analyzed using a model taking into account the contribution to the capacitance from the entire surface of the wires. This made it possible to numerically estimate the density profile of free charge carriers precisely in the wire array, which showed good numerical agreement with the doping level in the original substrates.
Keywords:silicon wires, solar cell, cryogenic etching, capacitance–voltage profiling.