Process for obtaining porous semiconductor structures

The invention relates to the semiconductor production technology, in particular to the processes for obtaining porous semiconductor structures.

The selective electrochemical process for obtaining semiconductors with nano- and microstructured surface is known, which includes depositing a grinder on the surface of the semiconductor, implanting ions in selected regions of the semiconductor surface, removing the electrode surface and removing this electrode.

The disadvantage of the present invention is that the entire surface of the semiconductor is not efficiently used and the possibility of obtaining regions with different porosity degrees is lacking.

The problem solved by the proposed invention is to increase the efficiency of using the surface of the semiconductor and to obtain semiconductors with the surface with different degrees of porosity.

The process according to the invention consists in the fact that о mask is deposited on the surface of the semiconductor, high energy ions are implanted on the uncoated regions, then the mask is removed and the semiconductor surface is subjected to electrochemical corrosion. The novelty is that before the corrosion on the surface of the repeated semiconductor, it is deposited only on the regions that have been implanted with high energy ions different from the previous one, and the mask is removed.

The result of the invention is that a structural surface of the semiconductor is obtained with the degree of porosity highlighted.

Example of embodiment of the invention

On the GaP semiconductor sample, cleaned with acetone or isopropyl alcohol, a 5 µm thick Ag metal mask was deposited, which selectively covers the surface of the GaP sample. High-energy argon ions were implanted in the uncoated regions at a dose of 10¹⁰ cm '². The implantation energy is 5 MeV. Then the GaP sample was rinsed in distilled water and the Ag metal mask was removed. Again, a metal mesh was deposited, covering the regions of the surface implanted with ions at the DI dose, and in the selected regions not covered by the second inn, high energy ions were implanted at the dose D2 = 10¹¹ cm '². The implantation energy is 5 MeV. Subsequently, from the GaP sample, rinsed in distilled water, the metallic Ag mask was removed. After this the entire surface implanted in aqueous H solution was electrochemically corrected₂SO₄ 5% for 5 ... 10 min, at 5 V.

As a result, for the region with dose DI, a porosity degree of 25% was obtained, and for the region with dose D2, the porosity degree constitutes 55%.