Optical Absorption in Polycrystalline CdTe Thin Films

Yıl 2006, Cilt: 1 Sayı: 5, 103 - 116, 01.04.2006

Bengül Zengir, Murat Bayhan, Sertap Kavasoğlu

Öz

Anahtar Kelimeler

-

Optical Absorption in Polycrystalline CdTe Thin Films

Öz

Saydam cam lam üzerine vakumda buharlaştırma tekniğiyle büyütülen çoklu kristal CdTe incefilmlerin soğurma katsayılarının 0.5-1.6eV foton enerji aralığındaki spektral dağılımı verilmektedir.Kullanılan metot sadece normal açı altında optiksel transmisyon ölçümünü gerekli kılar ve girişimsaçaklarının spektral genişliklerinin ve spektral konumlarının incelenmesine dayanır. Foton enerjisinindüşük olduğu bölgede ışığın soğurumu yapısal kusurlardan dolayı olabilir. Optik band aralığınındışındaki bölgede teorik olarak hesaplanan transmisyon deneysel olarak elde edilen spektruma oldukçayakın olduğu saptandı. Bileşik yarı-iletkenlere özgü yasak enerji aralığının kenarında yapıdüzensizliğiyle ilişkili üstel (Urbach) kuyruğu gözlendi. İşlenmemiş filmlerin optiksel band aralığıTauc denklemleri kullanılarak ~1.53 eV olarak hesaplandı

Anahtar Kelimeler

Soğurum katsayısı, CdTe ince filmi, Yasak enerji aralığı

Kaynakça

• Bayhan, M, PhD Thesis, Preparation and Characterisation of n-CdS/p-CdTe Thin Film Solar Cells (University of Durham, 1994, pp. 42).
• Britt, J and Ferekides, C, Thin-Film CdS/CdTe Solar Cell with 15.8% Efficiency, Applied Physics Letters, 62 (1993), pp. 2851-2852.
• Burgelman, M, Verschraegen, J, Degrave, S, and Nollet, P, Analysis of CdTe Solar Cells in Relation to Materials Issues, Thin Solid Films, 480-481, (2005), pp. 392-398
• Compaan, A. D, Gupta, A, Lee, S, Wang, S, Drayton, J, High Efficiency Magnetron Sputtered CdS/CdTe Solar Cells, Solar Energy, 77 (6) (2004), pp. 815-822.
• Enloe, W. S, Parker, J. C, Vespoli, J, Meyers, T. H, Harper, R. L, and Schetzina, J. F, An Electroreflectance Study of CdTe, Journal of Applied Physics, 61 (5) (1987), pp. 2005-2010.
• Hishikawa, Y, Nakamura, N, Tsuda, S, Nakano, S, Kishi, Y, Kuwano, Y, Interference-Free Determination of the Optical Absorption Coefficient and the Optical Gap of Amorphous Silicon Thin Films, Japanese Journal of Applied Physics, 30 (1991), pp. 1008-1014.
• Kushev, D. B, Zheleva, N. N, Demakopoulou, Y, Siapkas, D, A New Method for the Determination of the Thickness, the Optical Constants and the Relaxation Time of Weakly Absorbing Semiconducting Thin Films, Infrared Physics, 26 (1986), pp. 385-393.
• Laaziz, Y, Bennouna, A, Chahboun, N, Outzourhit, A, Ameziane, E. L, Optical Characterization of Low Optical Thickness Thin Films From Transmittance and Back Reflectance Measurements, Thin Solid Films, 372 (2000), pp. 149-155.
• Limousin, O, New Trends in CdTe and CdZnTe Detectors for X- and Gamma-ray Applications, Nuclear Instruments and Methods in Physics Research A, 504 (2003), pp. 24-37.
• Manifacier, J. C, Gasiot, J, Fillard, J. P, A Simple Method for the Determination of the Optical Constants n, k and the Thickness of a Weakly Absorbing Thin Film, Journal of Physics E: Scientific Instruments, 9 (1976), pp. 1002-1004.
• Minkov, D, Computation of the Optical Constants of a Thin Dielectric Layer on a Transmitting Substrate from the Reflection Spectrum at Inclined Incidence of Light, Journal of the Optical Society of America A, 8 (2) (1991), pp. 306-310.
• Olego, D. J, Faurie, J. P, Sivananthan, S, Raccah, P. M, Optoelectronic Properties of Cd1-xZnxTe Films Grown by Molecular Beam Epitaxy on GaAs Substrates, Applied Physics Letters, 47 (11) (1985), pp. 1172-1174.
• Pankove, J. I, Optical Process in Semiconductors, (New Jersey: Prentice-Hall, Inc., Englewood Cliffs, 1971, pp.36).
• Paulson, P. D, Dutta, V, Study of in situ CdCl2 Treatment on CSS Deposited CdTe Films and CdS/CdTe Solar Cells, Thin Solid Films, 370 (1-2) (2000), pp. 299-306.
• Pikhtin, A. N, Yas’kov, A. D, Refraction of Light in Semiconductors (Review) Soviet Physics Semiconductors, 22 (6) (1988), pp. 613-626
• Poruba, A, Fejfar, A, Reme_, Z, _pringer, J, Van__ek, M, Ko_ka, J, Meier, J, Torres, P, Shah, A, Optical Absorption and Light Scattering in Microcrystalline Silicon Thin Films and Solar Cells, Journal of Applied Physics, 88 (1) (2000), pp. 148-160.
• Swanepoel, R, Determination of the Thickness and Optical Constants of Amorphous Silicon, Journal of Physics E: Scientific Instruments., 16 (1983), pp. 1214-1222.
• Turner, A. K, Woodcock, J. M, Özsan, M. E, Cunningham, D. W, Johnson, D. R, Marshall, R. J, Mason, N. B, Oktik, Ş, Patterson, M. H, Ransome, S. J, Roberts, S, Sadeghi, M, Sherborne, J. M, Sivapathasundaram, D, Walls, I. A, BP Solar Thin Film CdTe Photovoltaic Technology, Solar Energy Materials and Solar Cells, 35, (1994), pp. 263-270.
• Vedam, K, Spectroscopic Ellipsometry: A Historical Overview, Thin Solid Films, 313-314 (1998), pp. 1-9.
• Vriens, L, Rippens, W, Optical Constants of Absorbing Thin Solid Films on a Substrate, Applied Optics, 22 (24) (1983), pp. 4105-4110.