Abstracts Book - IMRC 2018

• SF2-P071
COMPARATIVE ANALYSIS OF THE OPTICAL, STRUCTURAL AND
ELECTRICAL PROPERTIES OF CdS THIN FILMS DEPOSITED BY
CHEMICAL BATH AND SPUTTERING. PERFORMANCE IN A
HETEROSTRUCTURE CDS/CDTE FOR SOLAR CELLS APPLICATION
David Santos Cruz 1 , Francisco de MouFlores 2 , Maria de la Luz Olvera Amador 1 , José Santos
Cruz 2
1 CINVESTAV-IPN, Departamento de Ingeniería Eléctrica-Sección de Electrónica del Estado
Sólido, Mexico. 2 Universidad Autónoma de Querétaro, Facultad de Química, Materiales-
Energía, Mexico.
Cadmium sulfide (CdS) is an n type semiconductor material, with a bandgap
oscillating between 2.4 to 2.6 eV. It presents two characteristic crystalline
structures, cubic, Zinc-Blenda type, and hexagonal-wurtzite type. Its optical
transmittance in the near ultraviolet-visible spectrum is high (greater than 70%),
this property makes it very attractive for being applied as window layer in solar
cells based on thin films. However, until now, the electrical resistivity decreasing
in CdS films is a challenge in the field of research. In this work, a comparative
study of the optical, structural and electrical properties of CdS thin films
deposited by both chemical bath and cathodic erosion is presented. The films
were optically characterized by their optical transmission measured by
spectrophotometry in the ultraviolet-visible range of 200 to 1100 nm and the
bandgaps were determined from these spectra by using the Tauc´s method.
Additionally, Raman spectroscopy and photoluminescence analyzes were
performed. The crystalline structure was characterized by X-ray diffraction. The
electrical characterization was developed by means of the 4-point probe, Van
der Pauw and Hall effect, thus determining the electrical resistivity, conductivity
type, carrier concentration and electron mobility. Film thicknesses were
measured directly by profilometry and confirmed by the Manifacier´s method.
Both deposited films (by chemical bath and sputtering) were separately applied
for manufacturing a glass/TCO/CdS /CdTe heterostructure to evaluate its
performance as solar cell by determining its characteristic current-voltage (IV)
curve under an 1.5 AM illumination.
Keywords: Thin films, Chemical bath deposition, Sputtering
Presenting authors email: d_asan_c@hotmail.com