• 센서학회지
• /
• 제16권1호
• /
• pp.1-6
• /
• 2007

A silver indium sulfide ($AgInS_{2}$) epilayer was grown by the hot wall epitaxy method, which has not been reported in the literature. The grown $AgInS_{2}$ epilayer has found to be a chalcopyrite structure and evaluated to be high quality crystal. From the photocurrent measurement in the temperature range from 30 K to 300 K, the two peaks of A and B were only observed, whereas the three peaks of A, B, and C were seen in the PC spectrum of 10 K. These peaks are ascribed to the band-to-band transition. The valence band splitting of $AgInS_{2}$ was investigated by means of the photocurrent measurement. The crystal field splitting, ${\Delta}cr$, and the spin orbit splitting, ${\Delta}so$, have been obtained to be 0.150 eV and 0.009 eV at 10 K, respectively. And, the energy band gap at room temperature has been determined to be 1.868 eV. Also, the temperature dependence of the energy band gap, $E_{g}$(T), was determined.

• 자원환경지질
• /
• 제23권1호
• /
• pp.25-33
• /
• 1990

Gold-silver deposits of Deogheun and Beopjeon mines are composed of veins emplaced in Jurassic granite batholith. Based on ore structure and ore mineralogy, four distinct stages of mineral deposition are recognized in these ore deposits. Gold and silver minerals in Deogheun and Beopjeon-A ore deposits are precipitated in stage III and stage II, respectively. Mineral constituents of ores from these deposits are pyrite, sphalerite, arsenopyrite, pyrrhotite, chalcopyrite, galena, tetrahedrite, electrum, quartz and rhodochrosite. Cubanite, argentite and pyrargyrite occur only in Deogheun ore deposits. Ag content of electrum range from 42 to 66 atomic % in both ore deposits. Filling temperature of fluid inclusion from both ore deposits are as follows; stage I, $211-289^{\circ}$ ; stage II, $205-290^{\circ}$ ; stage III, $190-260^{\circ}$ ; stage IV, $136-222^{\circ}$ in Deogheun ore deposits. In Beopjeon-A ore deposits, stage I, $255-305^{\circ}$ ; stage II, $135-222^{\circ}$ ; stage III, $148-256^{\circ}$ ; stage IV, $103-134^{\circ}$. Salinities of fluid inclusions range from 1.6-8.5 wt. % equivalent NaCl in both ore deposits. Sulfur fugacities through stage II and III in Deogheun ore deposits inferred from data of mineral assemblage and fluid inclusion range from $10^{-11.0}-10^{-16.1}$1bars. Fluid pressure estimated from fluid inclusions which reveal boiling evidence range from 30-190 bars during mineralization in Deogheun ore deposits.

• 자원환경지질
• /
• 제29권2호
• /
• pp.139-150
• /
• 1996

The Yucheon Bi deposits at Cheongha, Gyeongsangbugdo, is of a middle Paleogene (49 Ma) vein type, and is hosted in sandstone and shale of Banyawal formation in Cretaceous age. Based on mineral paragenesis, vein structure and mineral assemblages, two minera1ization stages were distinguished. The stage I consists of quartz with small amount of chlorite, pyrite, epidote, hal1oysite, vermiculite, serpentine and rutile associated with sericitization. The stage II is characterized by Bi minera1ization such as bismuthinite, Bi-Cu-Pb-S mineral, tetradymite, native gold, pyrite, pyrrhotite, arsenopyrite, wolframite, rutile, hematite, sphalerite, chalcopyrite, galena with alteration of sericite, chlorite, K-feldspar, albite and epidote. Fluid inclusion data indicate that fluid temperature and NaCl equivalent wt.% salinity range from 431 to $150^{\circ}C$ and from 19.2 to 0.18wt.% in the stage II. Evidence of boiling during the base-metal minera1ization indicates pressures 241 to 260 bars. Sulfur fugacity($-log\;f_{S2}$) deduced by mineral assemblages and compositions ranges from 5.1 to 5.7atm in early stage, from > 8.4 atm in middle stage and from 13.5 to 19.3 atm in late stage. It suggests that complex histories of progressive coo1ing, dilution and boiling were occurred by the mixing of the fluids. The ${\delta}^{34}S$, ${\delta}^{18}O$ and ${\delta}D$ data range from 2.5 to 3.9%, -0.5 to -4.1% and -29.7 to -47%, respectively. It indicated that hydrothermal fluids may be magmatic origin with boiling and mixing of meteoric water increasing paragenetic time.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2009년도 추계학술대회 논문집
• /
• pp.400-400
• /
• 2009

Despite the success of Cu(In,Ga)$Se_2$ (CIGS) based PV technology now emerging in several industrial initiatives, concerns about the cost of In and Ga are often expressed. It is believed that the cost of those elements will eventually limit the cost reduction of this technology. One candidate to replace CIGS is $Cu_2ZnSnSe_4$ (CZTSe), fabricated by co-evaporation technique. Co-evaporation technique will be one of the best methods to control film composition. This type of absorber derives from the $CuInSe^2$ chalcopyrite structure by substituting half of the indium atoms with zinc and other half with tin. Energy bandgap of this material has been reported to range from 0.8eV for selenide to 1.5eV for the sulfide and large coefficient in the order of $10^{14}cm^{-1}$, which means large possibility of commercial production of the most suitable absorber by using the CZTSe film. In this work, Effects of substrate temperature of $Cu_2ZnSnSe_4$ absorber layer on the performance of thin films solar cells were investigated. We reported on some of the absorber properties and device results.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
• /
• pp.53-53
• /
• 2011

This paper describes results for surface and bulk characterization of the most promising thin film solar cell material for high performance devices, (Ag,Cu) (In,Ga) Se2 (ACIGS). This material in particular exhibits a range of exotic behaviors. The surface and general materials science of the material also has direct implications for the operation of solar cells based upon it. Some of the techniques and results described will include scanning probe (AFM, STM, KPFM) measurements of epitaxial films of different surface orientations, photoelectron spectroscopy and inverse photoemission, Auger electron spectroscopy, and more. Bulk measurements are included as support for the surface measurements such as cathodoluminescence imaging around grain boundaries and showing surface recombination effects, and transmission electron microscopy to verify the surface growth behaviors to be equilibrium rather than kinetic phenomena. The results show that the polar close packed surface of CIGS is the lowest energy surface by far. This surface is expected to be reconstructed to eliminate the surface charge. However, the AgInSe2 compound has yielded excellent atomic-resolution images of the surface with no evidence of surface reconstruction. Similar imaging of CuInSe2 has proven more difficult and no atomic resolution images have been obtained, although current imaging tunneling spectroscopy images show electronic structure variations on the atomic scale. A discussion of the reasons why this may be the case is given. The surface composition and grain boundary compositions match the bulk chemistry exactly in as-grow films. However, the deposition of the heterojunction forming the device alters this chemistry, leading to a strongly n-type surface. This also directly explains unpinning of the Fermi level and the operation of the resulting devices when heterojunctions are formed with the CIGS. These results are linked to device performance through simulation of the characteristic operating behaviors of the cells using models developed in my laboratory.

• 자원환경지질
• /
• 제22권3호
• /
• pp.237-252
• /
• 1989

The Inseong gold-silver mine is located 3Km northwest of Suanbo, Choongcheongbugdo, Republic of Korea. The mine occurs in the shear zone formed by tension fractures within the Hwanggangri Formation of the Ogcheon metamorphic belt. Ore minerals found in the gold-silver bearing hydrothermal quartz vein composed mainly of pyrite, arsenopyrite, sphalerite, galena and minor amount of chalcopyrite, pyrrhotite, stannite, bismuthininte, native bismuth, chalcocite, electrum and tellurian canfieldite(?). The gangue minerals are quartz, calcite, chlorite and rhodochrocite. Wallrock alterations such as chloritization, silicitication, pyritization, carbonitization and sericitization can be observed in or around the quartz vein. According to the paragenetic sequence, quartz vein structure and mineral assemnlages, three different stages of ore formation can be recognized. The physico-chemical environment of ore formation in this deposit shows slight variation from stage to stage, but the condition of main ore deposition can be summarized as follows. Fluid inclusion, S-istope geothermometry and geothermometry based on mineral chemistry by use of arsenopyrite and chlorite show the ore was formed at temperature between 399 and $210^{\circ}C$ from fluids with salinities of 3.3-5.8 wt.% equivalent NaCl. It indicates that pressure during the mineralization is less than 0.6 Kb corresponding to a depth not greater than 1Km. S-isotope data suggests that thermal fluid may have magmatic origin wit some degree of mixing with meteoric water. In coclusion, the Inseong gold-silver deposit was formed at shallow depth and relatively high-temperature possibly with steep geothermal gradient under xenothermal condition.

• 자원환경지질
• /
• 제48권6호
• /
• pp.525-536
• /
• 2015

트라피체 프로젝트는 현재 탐사단계 중 후기(Advanced exploration)단계의 프로젝트이며 안다우아일라스-야우리 광상구 연변에 나타나는 다양한 반암 광상 중 일부라고 볼 수 있다. 이 광상은 몬조나이트 반암의 관입과 관계가 있으며, 또한, 올리고세 각력 파이프와 밀접한 관계를 가지고 있는 광상이다. 광화작용은 일차 유화광물인 황철석, 황동석, 반동석 및 휘수연석으로 구성된다. 2차 유화광물인 휘동석, 코벨라이트, 다이게나이트가 산출되며 산화동으로서 공작석, 흑동석, 적동석등이 산출된다. 침출작용(lixiviation)이나 부화과정 결과로서, 광화작용은 비전형적인 누대구조를 보여주기도 한다. 각력과 반암이 나타나는 구역에서는 수직적인 누대구조를 보여주는데, 북쪽 인근에서는 침출대, 2차부화대, 전이대 및 초생광화대가 나타나고 광상의 서쪽에서는 산화대 및 혼합대가 좁게 나타난다. 광상의 추정자원은 920 Mt @ 0.41% Cu이며 한계품위는 0.15%로 산정하고 있다.

• 한국재료학회지
• /
• 제23권11호
• /
• pp.638-642
• /
• 2013

Chalcopyrite $CuInSe_2$(CIS) is considered to be an effective light-absorbing material for thin film photovoltaic solar cells. CIS thin films have been electrodeposited onto Mo coated and ITO glass substrates in potentiostatic mode at room temperature. The deposition mechanism of CIS thin films has been studied using the cyclic voltammetry (CV) technique. A cyclic voltammetric study was performed in unitary Cu, In, and Se systems, binary Cu-Se and In-Se systems, and a ternary Cu-In-Se system. The reduction peaks of the ITO substrate were examined in separate $Cu^{2+}$, $In^{3+}$, and $Se^{4+}$ solutions. Electrodeposition experiments were conducted with varying deposition potentials and electrolyte bath conditions. The morphological and compositional properties of the CIS thin films were examined by field emission scanning electron microscopy (FE-SEM) and energy dispersive spectroscopy (EDS). The surface morphology of as-deposited CIS films exhibits spherical and large-sized clusters. The deposition potential has a significant effect on the film morphology and/or grain size, such that the structure tended to grow according to the increase of the deposition potential. A CIS layer deposited at -0.6 V nearly approached the stoichiometric ratio of $CuIn_{0.8}Se_{1.8}$. The growth potential plays an important role in controlling the stoichiometry of CIS films.

• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제52권7호
• /
• pp.275-281
• /
• 2003

$Zn_{0.5}Cd_{0.5}Al_{2}Se_{4}$ and $Zn_{0.5}Cd_{0.5}Al_{2}Se_{4}$:$Co^{2+}$ single crystals were grown by CTR method. The grown single crystals have defect chalcopyrite structure with lattice constant a=5.5966$\AA$, c=10.8042$\AA$ for the pure, a=5.6543$\AA$, c=10.8205$\AA$ for the Co-doped single crystal, respectively. The optical energy band gap was given as indirect band gap. The optical energy band gap was decreased according to add of Co-impurity Temperature dependence of optical energy band gap was fitted well to the Varshni equation. From this relation, we can deduced the entropy, enthalpy and heat capacity. Also, we can observed the Co-impurity optical absorption peaks assigned to the $Co^{2+}$ ion sited at the $T_{d}$ symmetry lattice and we consider that they were attributed to the electron transitions between energy levels of ions.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
• /
• pp.379-380
• /
• 2005

Single phase $CuInS_2$ thin film with a highest diffraction peak (112) at a diffraction angle ($2\Theta$) of $27.7^{\circ}$ was well made by SEL method at annealing temperature of $250^{\circ}C$ and annealing hour of 60 min in vacuum of $10^{-3}$ Torr or in S ambience for an hour. And the peak of diffraction intensity at miller index (112) of $CuInS_2$ thin film annealed in S ambience was shown a little higher about 11 % than in only vacuum. Single phase $CuInS_2$ thin films were appeared from 0.85 to 1.26 of Cu/In composition ratio and sulfur composition ratios of $CuInS_2$ thin films fabricated in S ambience were all over 50 atom%. Also when $CuInS_2$ composition ratio was 1.03, $CuInS_2$ thin film with chalcopyrite structure had the highest XRD peak (112). The largest lattice constant of a and grain size of $CuInS_2$ thin film in S ambience was 5.63 ${\AA}$ and 1.2 ${\mu}m$ respectively. And the films in S ambience were all p-conduction type with resistivities of around $10^{-1}{\Omega}cm$.