The Study of Electrodeposition of CuInSe2 Nanostructures into Porous Alumite Substrate Prepared in Oxalic Acid

[[abstract]]本論文將進行電鍍CuInSe2 (CIS) 於陽極氧化鋁孔洞之中，並以化學水浴法沉積ZnS或CdS，形成以CIS為主要吸收層之奈米結構太陽能電池。利用此技術製造p型I-III-VI族半導體化合物之奈米線結構，並研究其光伏特性，希望藉此能夠提升太陽電池效率。 在本論文當中，氧化鋁孔洞及CIS奈米線將使用電鍍的方式來製作。電化學沉積的方式是一種簡單且可以大面積生產的製程，除此亦可藉由控制電壓的方式來控制CIS奈米線的比例、大小和長度。電鍍CIS於氧化鋁孔洞時，使用脈衝電壓-10V預鍍數秒，因其較大電場而破壞氧化鋁孔洞底層殘留之氧化鋁阻障層，從而幫助CIS沉積於孔洞之中。 本論文電鍍所製作之CIS奈米結構，其氧化鋁孔洞直徑為50 ~ 60nm，長度為2 ~ 3μm，最佳脈衝沉積電壓為-0.5V，退火溫度為250oC，其CuInSe2 / Al2O3之片電阻值約為2 ~ 15M Ω/sq 。CBD沉積ZnS後順向偏壓大約為1.7V，逆向偏壓為-1.5V；沉積CdS後順向偏為1.5V，逆向偏壓為 -1.3V。[[abstract]]This investigation is focus on the photovoltaics effect of the CuInSe2 (CIS) nanowires structure, which is prepared by electrodeposition into the anodic aluminum oxide (AAO). On top of CIS nanowires, CdS or ZnS buffer layer will be deposited by chemical bath deposition (CBD) for structure of CIS solar cells. We can employ this technology to produce nanowires structure of the I-III-VI group semiconductor compound, thus opening a new hope to higher efficiency thin film solar cells. In this study, the AAO and CIS nanowires is prepared by electrodeposition. The method is relatively simple and adaptable to large scale production. It also offers the potential to control the composition, siz and length of CIS nanowires arrays. A first deposition was performed at pulse -10V for few seconds to perforate any residual barrier layer. In our study CIS nanowires is 50 ~ 60 nm in diameter and as long as 2 ~ 3μm. Voltage pulses of an amplitude of -0.5V is employed during electrodeposition. The electrodeposited CIS nanowires is annealed at 250oC to improve stoichiometry and crystallinity. The ohm – squire of CuInSe2 / Al2O3 is 0.5 ~ 5M Ω/sq. The cell with CBD ZnS has the Vfoward and Vrevers of 1.7V and -1.5V respectively; the cell with CBD CdS has the Vfoward and Vrevers of 1.5V and -1.3V respectively