Optical Absorption in Polycrystalline CdTe Thin Films

Abstract

Keywords

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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

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