Study The Effect of Thickness on The Structural and Optical constant of CdSe Thin Films

Abstract

In this research , pure (CdSe) thin films with a different thickness ( 300 ,
500 ,700 ,900) ± 20 nm was deposited on glass substrate in room temperature
JOURNAL OF COLLEGE OF EDUCATION ······ 2017····· NO1
250
( 300K ) with deposition rate (0.7±0.01) nm /sec by thermal evaporation under
vacuum technique , and then studies their structure and optical properties .
The resultant of the structural analysis showed that all films with all
thickness prepared were polycrystalline in nature and have hexagonal type
structure with atomic growth in three crystal orientation which it [002] , [102]
and [103] with Preferred orientation along [002] plane for all Prepared films.
The optical analysis measurement showed that all prepared films have
absorption coefficient with a value larger than (∝ > 104 ????????−1) and this value
was increased when increasing the film thickness especiallyrange of electromagnetic spectrum , the optical energy gap was founded in
the range ( 1.70 -1.72 ) eV.