Nanostructures based on III-V semiconductors

Nanostructure is a structure, especially a semiconductor device, which has dimensions of only a few nanometres. The III-V semiconductors are materials which are obtained by combining group III. A elements with group V. A elements (e.g. GaP, GaAs,…).

Our department research is also growth of GaP (gallium phosphide) nanostructures (nanowires, nanocones) for different applications. The nanostructures are grown by MOVPE (Metal Organic Vapour Phase Epitaxy) technique. The fields of application of thenanostructures are wide from optical and chemical to biological applications.

GaP nanowires have potential for application as antireflection coating for solar cells (Fig. 1). Role of antireflection coating is avoiding reflection of phonons from surface and allowing their absorption into the solar cells. Main benefit of using nanowires as antireflective coating is their broadband and omni-directional character. However, nanowires are fragile and they can break under tiny mechanical stresses. A way to avoid this problem is to fill gaps between individual NWs with another material, e.g. thin nanostructural layer as ZnO (zinc oxide). The other benefit of using of ZnO is widening of spectral sensitivity range of solar cells to the UV region.

SEM obrázky: GaP nanodrôty (vľavo), GaP nanodrôty pokryté vrstvou ZnO (vpravo).

SEM images: GaP nanowires (left), GaP nanowires covered with ZnO layer (right).

GaP nanocones covered with Ag nanoparticles (Fig. 2) are very promising material for surface enhanced Raman spectroscopy (SERS = Surface enhanced Raman spectroscopy). SERS is selective and high sensitive method for identification of chemical species in a wide variety of fields, including materials science, biosensing, and electrochemistry. The main advantage of SERS is detection of chemicals at very low concentrations (in the range from 10-2 do 10-20 M).

SEM obrázok GaP nanokužeľov pokrytých Ag nanočasticami.

SEM image of GaP nanocones covered with Ag nanoparticles.

Publications:

Novák, J., Laurenčíková, A., Eliáš, P., Hasenöhrl, S., Sojková, M., Dobročka, E., Kováč, J.jr., Kováč, J., Ďurišová, J., and Pudiš, D.: Nanorods and nanocones for advanced sensor applications, Applied Surface Sci 461 (2018) 61-65.

Lettrichová, I., Laurenčíková, A., Pudiš, D., Novák, J., Goraus, M., Kováč, J.jr., Gaso, P., and Nevrela, J.: 2D periodic structures patterned on 3D surfaces by interference lithography for SERS, Applied Surface Sci 461 (2018) 171-174.

Laurenčíková, A., Eliáš, P., Hasenöhrl, S., Kováč, J.jr., Szobolovszký, R., and Novák, J.: GaP nanocones covered with silver nanoparticles for surface-enhanced Raman spectroscopy, Applied Surface Sci 461 (2018) 149-153.

Kúdela, R., Šoltýs, J., Kučera, M., Stoklas, R., Gucmann, F., Blaho, J., Mičušík, M., Pohorelec, O., Gregor, M., Brytavskyi, I.V., Dobročka, E., and Gregušová, D.: Technology and application of in-situ AlOx layers on III-V semiconductors, Applied Surface Sci 461 (2018) 33-38.

Laurenčíková, A., Novotný, I., Hasenöhrl, S., Dérer, J., Eliáš, P., Kováč, J., Kováč, J., Dobročka, E., Novák, J., : Formation of a compact Ga-doped ZnO layer over vertical free-standing GaP nanowires. Applied Surface Sci 395 (2017) 162-165.

Stoklas, R., Gregušová, D., Blaho, M., Fröhlich, K., Novák, J., Matys, M., Yatabe, Z., Kordoš, P., Hashizume, T., : Influence of oxygen-plasma treatment on AlGaN/GaN metal-oxide-semiconductor heterostructure field-effect transistors with HfO2 by atomic layer deposition: leakage current and density of states reduction,. Semicond. Sci Technol. 32 (2017) 045018.

Novák, J., Laurenčíková, A., Hasenöhrl, S., Eliáš, P., Kováč, J., : Methanol sensor for integration with GaP nanowire photocathode. Proc. SPIE 10248, Nanotechnology VIII (2017) 102480E.

Novák, J., Laurenčíková, A., Hasenöhrl, S., Eliáš, P., Novotný, I., Kováč, J., Valentin, M., Kováč, J., Ďurišová, J., Pudiš, D., : Optical and mechanical properties of a compact ZnO layer with embedded GaP nanowires. Applied Surface Sci 395 (2017) 180-184.

Gucmann, F., Kúdela, R., Rosová, A., Dobročka, E., Micusik, M., Gregušová, D., : Optimization of UV-assisted wet oxidation of GaAs,. J. Vacuum Sci Technol. B 35 (2017) 01A116. (VEGA 2/0105/13). (APVV 15-0243). (CENTE II).

Gregušová, D., Gucmann, F., Kúdela, R., Mičušík, M., Stoklas, R., Válik, L., Greguš, J., Blaho, M., Kordoš, P., : Properties of InGaAs/GaAs metal-oxide-semiconductor heterostructure field-effect transistors modified by surface treatment,. Applied Surface Sci 395 (2017) 140-144. (VEGA 2/0105/13). (CENTE). (APVV 14-0297).

Mikulics, M., Arango, Y., Winden, A., Adam, R., Hardtdegen, A., Grützmacher, D., Plinski, E., Gregušová, D.,Novák, J., Kordoš, P., Moonshiram, A., Marso, M., Sofer, Z., Lüth, H., Hardtdegen, H., : Direct electro-optical pumping for hybrid CdSe nanocrystal/III-nitride based nano-light-emitting diodes. Applied Phys. Lett. 108 (2016) 061107.

Gucmann, F., Kúdela, R., Kordoš, P., Dobročka, E., Gaži, Š., Dérer, J., Liday, J., Vogrinčič, P., Gregušová, D., : III-As heterostructure field-effect transistors with recessed ex-situ gate oxide by O2 plasma-oxidized GaAs cap. J. Vacuum Sci Technol. B 33 (2015) 01A111. (VEGA 2/0105/13). (VEGA 2/0098/13). (CENTE).

Laurenčíková, A., Eliáš, P., Hasenöhrl, S., Kováč, J., Mikolášek, M., Vávra, I., Novák, J., : Analysis of the core–shell interface between zinc-blende GaP and wurtzite ZnO. Solid-State Electr. 100 (2014) 7-10.

Eliáš, P., Hasenöhrl, S., Laurenčíková, A., Rosová, A., Novák, J., : Annealing of gold nanoparticles on GaP(111)B: initial stage of GaP nanowire growth. Phys. Status Solidi RRL 8 (2014) 321-324.

Novák, J., Šutta, P., Vávra, I., Eliáš, P., Hasenöhrl, S., Laurenčíková, A., Novotný, I., : Columnar microstructure of the ZnO shell layer deposited on the GaP nanowires. Applied Surface Sci 312 (2014) 162-166.