Bulk ofZnxSe100x (x¼10, 20and40at%)waspreparedbytheusualquenchmelttechnique.Thinfilms
of thesecompositionswerepreparedbythermalevaporation.Differentialthermalanalyses(DTA)on
powder samplesundernon-isothermalconditionsshowthattheglasstransitiontemperature Tg
increasedandcrystallizationtemperature Tp decreasedwithincreasingZncontent.Theaverageparticle
size ofthecrystallineZnSephasededucedfromX-raydiffraction(XRD)patternsshowadecreasewith
increasingZncontent.Theseresultswereconfirmedwiththeresultsobtainedbyscanningelectron
microscopy(SEM).
The opticalpropertiesofZnxSe100x have beenstudiedatawavelengthrange(300–900nm),andit
was foundthattheopticalbandgap(Eg) increaseswithincreasingZnconcentrationintheZnxSe100x
system. TheresultscanbeinterpretedonthebasisofthechemicalbondapproachproposedbyBicermo
and Ovshinsky.Thevalueoftheextinctioncoefficient(k) decreaseswithincreasingwavelengthandZn
content.
On theotherhand,theopticalenergygap(Eg) decreasedwithincreasingtheannealingtemperature
for Zn10Se90 thin films.TheseresultscanbeinterpretedbytheDavisandMottemodel.