Sheet resistance-temperature dependence, thermal and electrical analysis of As40S60-xSex thin films
Abstract
This framework focuses fundamentally on sheet resistance, Rs, measurements for the As40S60−xSex thin flms with [(0≤ x ≥60)
at.%] for thickness of the flm and heating rate of 1000 nm and 5 K/min, respectively. Then, we can adapt these measurements
to study the thermal and electrical properties by which we can reduce the time and efort spent. The thermal and electrical
analysis in this work appears in a new format without the need for a procedure to calculate the thermal measurements from
bulk material of the studied sample. The same is true for electrical properties where electrical measurements need not be
necessarily carried out. In this work, we will focus frst on obtaining the sheet resistance, Rs of thin flms whose surface thick-
ness is equal to 1000 nm for chalcogenide As40S60−xSex thin flms with [(0≤ x ≥60) at.%] at a heating rate of 5 K/min, in the
temperature range from 300 to 435 K. This range was sufcient to highlight on two important regions in the sheet resistance
curve and through the derivation of sheet resistance as a function of temperature, there was clear evidence of one crystalliza-
tion region for the studied samples. Second, the thermal data we obtained were used to complete the thermal calculations and
then the electrical calculations. The activation energies of crystallization were evaluated. The nucleation and growth order
parameter n, and the dimension order parameter m, were also computed and discussed. The activation energy, Ec, and Avrami
index, n, were obtained by analyzing the data via JMA methods. The results indicated that the transformation from amor-
phous to crystalline phases is a complex process that includes diferent mechanisms of nucleation and growth. The change
of activation energy with volume of crystalline fraction was determined. The crystalline phases for the as-deposited and
annealed flms were identifed using X-ray difraction (XRD). The electrical results of the investigated sample appear in two
types of conduction channels which contribute to two conduction mechanisms in the crystallized region. In the extended and
hopping states regions, the activation energies ΔE, two pre-exponential factors and other parameters were computed.