CuInS₂ thin films were produced by a two-stage process by means of the sulfurisation of magnetron-sputtered metallic precursor layers on molybdenum-covered soda-lime glass substrates. Terahertz pulse generation from the surface of CuInS₂ thin films excited by femtosecond laser pulses was studied. Terahertz radiation efficiency is dependent on the stoichiometry of the films obtained. The interface formation between vacuum-evaporated CdS and CuInS₂ thin films was studied by photoelectron spectroscopy using synchrotron radiation. The valence band offset of 0.7 ± 0.1 eV was determined for the CdS/CuInS₂ heterojunction.

Keywords: thin film, CuInS₂, photovoltaic absorbers, sulfurisation, terahertz radiation, photoelectron spectroscopy
PACS: 68.35.Ct, 79.60.Dp, 79.60.Jv, 88.40.jn

PLONŲJŲ CuInS₂ SLUOKSNIŲ TERAHERCINĖS SPINDULIUOTĖS IR FOTOELEKTRONINĖS EMISIJOS TYRIMAS
S. Balakauskas^a, A. Koroliov^a, S. Grebinskij^a , M. Senulis^a,
K. Šliužienė^a, V. Lisauskas^a, S. Mickevičius^a , R.L. Johnson^b
aFizinių ir technologijos mokslų centras, Vilnius, Lietuva
^bVokietijos elektronų sinchrotronas (DESY), Hamburgas,Vokietija

CuInS₂ plonieji sluoksniai buvo pagaminti sulfitizuojant magnetroninio dulkinimo būdu nusodintus sluoksnius ant molibdenu dengtų stiklo padėklų. Ištirtas terahercinių impulsų generavimas iš CuInS₂ plonųjų sluoksnių paviršių, sužadintų femtosekundiniais lazerio impulsais. Terahercinės spinduliuotės efektyvumas priklauso nuo plonųjų sluoksnių stechiometrijos ir morfologijos. Sandūros formavimas tarp vakuume garinto CdS ir CuInS₂ plonųjų sluoksnių buvo tiriamas rentgeno fotoelektronine spektroskopija naudojant sinchrotroninę spinduliuotę. CdS ir CIS valentinių juostų netolydumas yra tiesiogiai nustatytas iš valentinės juostos skirtuminių spektrų ir yra ≈ 0,7 ± 0,1 eV.

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