Author/Authors :
Fortunato، نويسنده , , E. and Raniero، نويسنده , , L. and Silva، نويسنده , , L. and Gonçalves، نويسنده , , Maria das Graças A. and Pimentel، نويسنده , , A. and Barquinha، نويسنده , , P. and ءguas، نويسنده , , H. and Pereira، نويسنده , , L. and Gonçalves، نويسنده , , G. and Ferreira، نويسنده , , I. and Elangovan، نويسنده , , E. and Martins، نويسنده , , R.، نويسنده ,
Abstract :
Transparent and highly conducting gallium zinc oxide (GZO) films were successfully deposited by RF sputtering at room temperature. A lowest resistivity of ∼2.8×10−4 Ω cm was achieved for a film thickness of 1100 nm (sheet resistance ∼2.5 Ω/□), with a Hall mobility of 18 cm2/V s and a carrier concentration of 1.3×1021 cm−3. The films are polycrystalline with a hexagonal structure having a strong crystallographic c-axis orientation. A linear dependence between the mobility and the crystallite size was obtained. The films are highly transparent (between 80% and 90% including the glass substrate) in the visible spectra with a refractive index of about 2, very similar to the value reported for the bulk material. These films were applied to single glass/TCO/pin hydrogenated amorphous silicon solar cells as front layer contact, leading to solar cells with efficiencies of about 9.52%. With the optimized deposition conditions, GZO films were also deposited on polymer (PEN) substrates and the obtained results are discussed.
Keywords :
transparent conducting oxides , Radio-frequency sputtering , Electrical properties , X-ray diffraction
