Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

HL: Fachverband Halbleiterphysik

HL 45: HL Posters III

HL 45.19: Poster

Donnerstag, 4. April 2019, 18:30–21:00, Poster E

Intermediate band solar cells - Two photon excitation of transition metal doped indium sulfide — •R. Hildebrandt¹, T. Jawinski¹, L. Wägele², H. von Wenckstern¹, R. Scheer², and M. Grundmann¹ — ¹Universität Leipzig, Felix Bloch Institute for Solid State Physics, Linnéstraße 5, 04103 Leipzig, Germany — ²Martin-Luther-Universität Halle-Wittenberg, Institute of Physics, Von-Dankelmann-Platz 3, 06120 Halle, Germany

The Shockley-Queisser limit for solar cell efficiency of 33.7% is based on a trade-off between generated photocurrent and photovoltage [1]. Intermediate band (IB) solar cells are proposed to overcome this trade-off by an additional two step photon absorption via states within the band gap [2]. Those states may be realized by quantum dots, band anti-crossing in highly mismatched alloys or deep level impurities.

In this work we pursue a deep level impurity approach for IB solar cells. The heterostructure consists of p-ZnCo₂O₄/i-In₂S₃/n-ZnO:Al [3]. The transition metal (V, Nb or Ti) doped In₂S₃ absorber material is deposited by thermal co-evaporation. ZnCo₂O₄ is deposited by pulsed laser deposition and ZnO:Al by HF-sputtering.

The devices were characterized with photocurrent measurements and with a two photon excitation setup provided by two UV/VIS and IR supercontinuum laser sources. Thermal admittance spectroscopy measurements revealed a sulfur vacancy at 400 meV depth.

[1] W. Shockley, H. J. Queisser: J. Appl. Phys., 32(3):510-519, 1961.

[2] A. Luque, A. Martí: Phys. Rev. Lett., 78(26):5014-5017, 1997.

[3] T. Jawinski et al.: pss (a), 215(1700827):1-6, 2018.