• Journal of Electrical Engineering and Technology
• /
• v.9 no.3
• /
• pp.1009-1015
• /
• 2014

Chalcopyrite $CuInSe_2$ (CIS) thin films were prepared without Se- / S-containing gas by co-sputtering using $CuSe_2$ and $InSe_2$ selenide-targets and rapid thermal annealing. The grain size increased to a maximum of 54.68 nm with a predominant (112) plane. The tetragonal distortion parameter ${\eta}$ decreased and the inter-planar spacing $d_{(112)}$ increased in the RTA-treated CIS thin films annealed at a $400^{\circ}C$, which indicates better crystal quality. The increased carrier concentration of RTA-treated p-type CIS thin films led to a decrease in resistivity due to an increase in Cu composition at annealing temperatures ${\geq}350^{\circ}C$. The optical band gap energy ($E_g$) of CIS thin films decreased to 1.127 eV in RTA-treated CIS thin films annealed at $400^{\circ}C$ due to the improved crystallinity, elevated carrier concentration and decreased In composition.

• 한국신재생에너지학회:학술대회논문집
• /
• 2007.06a
• /
• pp.257-260
• /
• 2007

In this study, $CuInSe_{2}$ (CISe) and $CuInZnSe_{2}$ (CIZSe) thin films were prepared on Corning 1737 glass by radio frequency (RF) magnetron sputtering from binary chalcogenide mixed powder targets. The targets were initially prepared by mixing appropriate weights of CuSe, InSe powder and various ZnSe contents. From the film bulk analysis result, it is observed that Zn concentration in the films increases proportionally with the addition of ZnSe in the sputtering targets. Under optimized conditions, CISe and CIZSe thin films grow as a chalcopyrite structure with strong (112), (220/204) and (312/116) reflections. Films are found to exhibit a high absorption coefficient of $10^{4}$ $cm^{-1}$. An increasing of optical band gap from 1.0 eV (CISe) to 1.25 eV (CIZSe) is found to be proportional with an increasing of Zn concentration as expected. All films have a p-type semiconductor characteristic with a carrier concentration in the order of 1014 $cm^{-3}$, a mobility about $10^{1}$ $cm^{2{\cdot}-1}{\cdot}s^{-1}$ and a resistivity at the range of $10^{2}-10^{6}$ W${\cdot}$m.

• 한국신재생에너지학회:학술대회논문집
• /
• 2009.06a
• /
• pp.83-84
• /
• 2009

Thin film solar cells based on CIGS continue to be a leading candidate for thin film photovoltaic devices due to their appropriate bandgap, long-term stability, and low-cost production. To date, the most successful technique for the deposition of a CIGS absorber layer has been based on the co-evaporation However, the evaporation process is difficult to scale-up for large-area manufacturing the sputtering and Selenizaton process has been a promising method for low-cost and large-scale production of high quality CIGS In this study, we have used Cu and CuIn alloy targets for precursor deposition the precursor deposited by sputtering Cu and CuIn targets and $CuInSe_2$ thin film is manufactured by Selenization process

• Korean Journal of Materials Research
• /
• v.21 no.10
• /
• pp.550-555
• /
• 2011

A high-quality CIGS film with a selenization process needs to be developed for low-cost and large-scale production. In this study, we used $Cu_2In_3$, CuGa and $Cu_2Se$ sputter targets for the deposition of a precursor. The precursor deposited by sputtering was selenized in Se vapor. The precursor layer deposited by the co-sputtering of $Cu_2In_3$, CuGa and $Cu_2Se$ showed a uniform distribution of Cu, In, Ga, and Se throughout the layer with Cu, In, CuIn, CuGa and $Cu_2Se$ phases. After selenization at $550^{\circ}C$ for 30 min, the CIGS film showed a double-layer microstructure with a large-grained top layer and a small-grained bottom layer. In the AES depth profile, In was found to have accumulated near the surface while Cu had accumulated in the middle of the CIGS film. By adding a Cu-In-Ga interlayer between the co-sputtered precursor layer and the Mo film and adding a thin $Cu_2Se$ layer onto the co-sputtered precursor layer, large CIGS grains throughout the film were produced. However, the Cu accumulated in the middle of CIGS film in this case as well. By supplying In, Ga and Se to the CIGS film, a uniform distribution of Cu, In, Ga and Se was achieved in the middle of the CIGS film.

• ETRI Journal
• /
• v.34 no.5
• /
• pp.779-782
• /
• 2012

$CuIn_{1-x}Ga_xSe_2$ (CIGS) thin films are grown on Mo/soda lime glass using a reactive sputtering process in which a Se cracker is used to deliver reactive Se molecules. The Cu and $(In_{0.7}Ga_{0.3})_2Se_3$ targets are simultaneously sputtered under the delivery of reactive Se. The effects of Se flux on film composition are investigated. The Cu/(In+Ga) composition ratio increases as the Se flux increases at a plasma power of less than 30 W for the Cu target. The (112) crystal orientation becomes dominant, and crystal grain size is larger with Se flux. The power conversion efficiency of a solar cell fabricated using an 800-nm CIGS film is 8.5%.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2014.11a
• /
• pp.250-251
• /
• 2014

This study introduces a simple deposition of $Cu_2O$ thin films with surface morphologies composed of columns, submicron-rods and submicron-branches on glass substrate from metallic Cu targets by tailoring the $Ar/O_2$ ratios during the sputtering. The obtained samples were used to fabricate gas sensor. The $H_2S$ sensing properties of the sensors at working temperatures from $100^{\circ}C$ to $300^{\circ}C$ were studied, in which $Cu_2O$ submicron-branches performed the best sensing property comparing with the rest morphologies. A transformation of $Cu_2O$ to $Cu_2S$ and CuS was consider as a main factor to the sensing mechanism of the sensors.