Preparation and Properties of Sintered CdS Films

Abstract

Polycrystal normalCdS films were prepared by coating normalCdS slurry on amorphous glass substrates and sintering in a nitrogen atmosphere in an attempt to produce films with properties suitable for fabricating all‐polycrystal normalCdS/normalCdTe heterojunction solar cells. The uniformity in microstructure and properties of these films has been correlated with starting particle size, volume percent of normalCdS powder in the slurry, and sintering conditions. The variations of electrical properties as a function of sintering temperature, sintering period, and the amount of sintering aid added have been correlated with the variations in carrier concentration, grain size, and microstructure. Additional effect of heating rate is also considered. By optimizing the preparation conditions, it is possible to produce transparent normalCdS films on amorphous glass substrates with an electron density in excess of 1018/cm3 and an electron mobility of 25 cm2/V‐s, The trap density of grain boundary is an order of 2×1011∼6.9×1011/cm2 for sintered normalCdS films.

Functionalization of nanomaterials with aryldiazonium salts

“…p-Carboxybenzenediazonium modified Si nanoparticles [171] were used in energy storage purposes. The p-carboxyphenyl-modified Si anodes in Li ion batteries exhibited reversible capacities of 1173 and 527 mA h g -1 at the 1 st and 50 th cycles, much higher than those of bare Si electrodes of only 56 and 62 mA h g -1 , respectively.…”

Photoconductive cells from screen‐printed and sintered cadmium sulfoselenide

“…The increasing value of R 10 suggests that, the sintering process is essentially complete after 30 min. When the sintering continued for more than 30 min, the effect of the chloride escape predominated (Yang and Im, 1986). The increase in resistance manifests itself as an additional series resistor and leads consequently to a decrease in slope k .…”

“…Development of R 10 values with increasing sintering time depended (in the range 30‐90 min) on the copper content; at 0.77‐0.86 mg Cu/g of powder the resistivity increased, at 2.2‐2.6 mg Cu/g powder the resistance did not change and at 3.1‐3.2 mg Cu/g powder the resistance decreased. Comparison with the general resistance – sintering time dependence (Yang and Im, 1986) suggests that copper inhibits sintering.…”

“…An addition of propylene glycol (PG) as a binder enabled screen‐printing of those mixtures (Sebastian et al , 1992; Garcia and Tomar, 1983). The screen‐printed layers of undoped CdS was studied in the context of window layers for heterojunction solar cells and photoelectrodes in photo‐electro‐chemical energy conversion systems (Yang and Im, 1986; Clemminck, 1988a, b; Sebastian and Calixto, 2000; Sharma et al , 2004). The following dependence of the layer resistance on the sintering time was found (Yang and Im, 1986): at the beginning of the sintering process the resistance decreased.…”

“…The screen‐printed layers of undoped CdS was studied in the context of window layers for heterojunction solar cells and photoelectrodes in photo‐electro‐chemical energy conversion systems (Yang and Im, 1986; Clemminck, 1988a, b; Sebastian and Calixto, 2000; Sharma et al , 2004). The following dependence of the layer resistance on the sintering time was found (Yang and Im, 1986): at the beginning of the sintering process the resistance decreased. After a minimum of resistance was reached, further sintering caused a resistance increase, at first slow and then more rapid.…”