THE EFFECT OF SUBSTRATE TEMPERATURES ON THE STRUCTURAL AND OPTICAL PROPERTIES FOR (CDS) THIN FILMS

In this research work optical and structural properties for (CdS) thin films werestudied .The (CdS) thin films were prepared by chemical spray pyrolysis with different substrate temperatures (250,300,350,400) C0 . Such a film was deposited on glass slides substrate of (350) nm thickness . The absorption coefficient was found to be greater than (104)cm-1 for all films and hence allowed for electrons transation . The value of the energy gap for (CdS) thin films prepared by the previous mentioned substrate temperatures became (2.3, 2.45, 2.55, 2.6) eV, respectively.The absorption coefficient ,transmittance ,refractive index and extinction coefficient) found to be dependent on the substrate temperatures . The structure of the (CdS) thin films have been diagnosed by the use of X-ray diffraction (XRD) . This technology was applied to the poly crystalline and Hexagonal structure . The results of the X-ray diffraction showed that grain-size increases with substrate temperature increasing.