【摘要】：能源危機(jī)和環(huán)境污染問(wèn)題日趨嚴(yán)重極大地促進(jìn)了光伏產(chǎn)業(yè)的發(fā)展。太陽(yáng)能作為新型的、最具發(fā)展?jié)摿Φ目稍偕茉粗豢梢杂行У亟鉀Q這兩大問(wèn)題。開(kāi)發(fā)太陽(yáng)能資源的新技術(shù)—太陽(yáng)電池的研究成為了光伏界的熱點(diǎn)。吸收層是太陽(yáng)電池的核心部件。黃銅礦晶體結(jié)構(gòu)的CuInSe2(CIS)半導(dǎo)體薄膜以其轉(zhuǎn)化效率高、抗輻射能力強(qiáng)、穩(wěn)定性好等特點(diǎn)備受研究者關(guān)注。本文通過(guò)摻雜Al元素部分替代In,制備CIAS薄膜作為CIAS薄膜太陽(yáng)電池的吸收層,降低了成本。改變薄膜組分中Al元素的含量,調(diào)節(jié)禁帶寬度,與太陽(yáng)光譜更好的配合。本實(shí)驗(yàn)采用真空蒸發(fā)法在普通玻璃基底上制備了CIAS薄膜,并結(jié)合真空硒化退火進(jìn)行處理。重點(diǎn)研究了摻雜元素Al含量、退火溫度及退火時(shí)間對(duì)CIAS薄膜結(jié)構(gòu)和性能的影響。分別采用X射線衍射、掃描電子顯微鏡、EDS能譜儀、臺(tái)階儀、霍爾效應(yīng)儀、紫外—可見(jiàn)—近紅外分光光度計(jì)對(duì)CIAS薄膜的結(jié)構(gòu)、形貌、成分、厚度及光電性能進(jìn)行了分析研究。結(jié)果表明:真空熱蒸發(fā)制備的CIAS薄膜結(jié)晶性都很完整,呈現(xiàn)出黃銅礦晶體結(jié)構(gòu),并且以(112)晶面優(yōu)先生長(zhǎng)。Al部分替代了CIS晶格中的In,減小了面間距。CIAS薄膜導(dǎo)電類(lèi)型為P型,載流子濃度達(dá)到1020數(shù)量級(jí)。隨著Al含量的減少,CIAS薄膜表現(xiàn)出顆粒大小均勻、界限分明、致密的結(jié)構(gòu)特征。對(duì)沉積態(tài)的CuIn1-xAlxSe2薄膜進(jìn)行真空硒化退火,選取350~550℃作為退火溫度,實(shí)驗(yàn)中發(fā)現(xiàn),退火有助于Cu、In、Al、Se原子在薄膜內(nèi)部的遷移、擴(kuò)散及相互結(jié)合。450℃退火后的薄膜成分更接近理想配比,光電性能適于作為光伏電池的吸收層。以450℃作為退火溫度,改變退火時(shí)間,結(jié)果表明,隨著退火時(shí)間的增加,薄膜的顆粒尺寸增大,電阻率表現(xiàn)出先增大后減小的趨勢(shì),載流子濃度和遷移率則相反,除了退火時(shí)間為2h的薄膜試樣外薄膜禁帶寬度逐漸增大。通過(guò)對(duì)比,退火溫度為450℃,退火時(shí)間為1h的CuIn0.7Al0.3Se2薄膜更適合作為CIAS薄膜太陽(yáng)電池的吸收層。
[Abstract]:Energy crisis and environmental pollution have greatly promoted the development of photovoltaic industry. Solar energy, as one of the new and most promising renewable energy sources, can effectively solve these two problems. The research of solar cells, a new technology for developing solar energy resources, has become a hot spot in photovoltaic field. Absorption layer is the core component of solar cell. Chalcopyrite crystal structure CuInSe2 (CIS) semiconductor thin films have attracted much attention because of their high conversion efficiency, strong radiation resistance and good stability. In this paper, CIAS thin films were prepared by doping Al elements partly instead of In, as the absorption layer of CIAS thin film solar cells, and the cost was reduced. The content of Al in the film is changed, the band gap is adjusted, and the solar spectrum is better coordinated. In this paper, CIAS thin films were prepared on ordinary glass substrates by vacuum evaporation, and were treated by vacuum selenization annealing. The effects of doping element Al content, annealing temperature and annealing time on the structure and properties of CIAS thin films were studied. The structure, morphology, composition, thickness and optoelectronic properties of CIAS thin films were studied by X-ray diffraction, scanning electron microscope (SEM) EDS spectrometer, step spectrometer, Hall effect instrument and UV-Vis near infrared spectrophotometer. The results show that the crystalline properties of CIAS thin films prepared by vacuum thermal evaporation are very complete, showing chalcopyrite crystal structure, and the (112) crystal plane preferential growth. Al partially replaces the In, in the CIS lattice to reduce the interplanar spacing. The conductive type of CIAS thin films is P type. The carrier concentration reaches 1020 orders of magnitude. With the decrease of Al content, the thin films exhibit uniform particle size, clear boundaries and dense structure. The deposited CuIn1-xAlxSe2 thin films were annealed by vacuum selenation, and 350 ~ 550 鈩，

本文編號(hào)：2261431