Growth and characterization of CdZnS thin film buffer layers by chemical bath deposition
In this paper we report the study of CdZnS thin films grown on the soda-lime glass (SLG) substrates by chemical bath deposition (CBD) process for buffer layer applications in CuGaSe/sub 2/ (CGS) solar cells. Structural, surface morphology, optical, and electrical properties of as-deposited CdZnS films were investigated by XRD, SEM, spectrophotometer, and four probes resistivity measurements as a function of Zn-composition in the solution. The CdZnS films have hexagonal structures. The grain size of CdZnS films was found to increase with increasing Zn-content in the solution. The films with 30% of Zn in the solution showed a better than 80% transmittance for wavelengths longer than 600 nm and film thickness less than 50 nm. The values of energy band gaps obtained are 2.40, 2.55, and 2.70 eV for Zn-content of 0, 30, and 50%, respectively. The resistivity of CdZnS films was found to increase as the Zn content increases.
Chemical bath codeposited CdSZnS film characterization
The chemical bath deposition of Cd1 − xZnxS thin films has been attempted following the usual methods employed for the chemical bath deposition of CdS and ZnS. The films obtained show compositions which vary almost linearly with the bath composition variation. However, the formation of a unique phase does not seem to be possible by this method, rather, the films seem to be composed of ZnS, CdS and Cd1 − xZnxS with an x value of 0.7 for all the bath compositions. The films obtained by this method have been characterized showing properties among the range found for pure CdS and ZnS, however the ZnS deposition process, which is slower than that of CdS, seems to dominate the deposition process.
AN ANALYSIS OF POLYMERIC THICK-FILM RESISTORS AS PRESSURE SENSORS
Abstract The strain-sensing characteristics of thick-film polymer-based resistors printed and cured on 96% alumina are presented. Two layout configurations have been analysed: planar and sandwich. Various strain-gauge characteristics have been studied, including the mechanical and temperature-dependent properties of the polymeric films. It has been shown that the planar polymer resistors exhibit low sensitivity, comparable to that of metal-foil gauges, whereas the MRM (metal-resistor-metal) configurations exhibit similar characteristics to those of cermet thick-film MRM gauges. It has also been observed that the mechanical properties of the polymeric films are significantly poorer than those of cermet-based gauges. This degradation in performance is attributed to the epoxy/pseudo-plastic structure of the polymeric thick-film resistor layer.