【摘要】：ZnS是一種重要的半導(dǎo)體基材,禁帶寬度是3.59~3.79e V,擁有優(yōu)越的特性,廣泛應(yīng)用于各種半導(dǎo)體元器件,如發(fā)光二極管、薄膜電致發(fā)光顯示器件、場致發(fā)光器件、紫外光探測器件等,還可作為銅銦硒基薄膜太陽能電池的n型窗口層,以其獨特的光譜轉(zhuǎn)換效果和無毒、環(huán)保價值替代CdS薄膜。ZnS經(jīng)適量的摻雜(如Sm、Mn等雜質(zhì)原子)可拓寬其光譜響應(yīng)范圍、調(diào)節(jié)其的發(fā)光效率,因此也可以作為熒光基材進(jìn)行研究。本文采用溶劑熱法,將硝酸鹽和硫粉分別作為鋅源和硫源、氧化釤為摻雜劑,在填充度為75%的條件下,制備了形狀規(guī)則、分散性好的微球狀ZnS及ZnS:Sm發(fā)光材料。探討了反應(yīng)溫度、反應(yīng)時間、反應(yīng)介質(zhì)、摻雜摩爾濃度等對微球表面形貌、物相結(jié)構(gòu)、熒光光譜的影響。實驗結(jié)果表明:反應(yīng)溫度越高,微球粒徑越大、晶體生長越完整,其發(fā)光強度隨溫度的上升先增后降;Sm3+的摻入量越多,其內(nèi)部生成的發(fā)光中心越多、發(fā)光強度越高,然而當(dāng)Sm3+摻雜量達(dá)到5%時,發(fā)光減弱;反應(yīng)介質(zhì)為乙醇時,生成的ZnS納米球團(tuán)聚嚴(yán)重,激發(fā)發(fā)射峰位置均藍(lán)移。綜合考慮,最佳的反應(yīng)條件為:反應(yīng)溫度170℃,反應(yīng)時間14h,Sm3+摻雜摩爾濃度為3%,反應(yīng)介質(zhì)為水。本文還通過真空蒸鍍法在鈉鈣硅玻璃基底上制備了ZnS及ZnS:Sm熒光薄膜,并較系統(tǒng)的研究了襯底溫度、摻雜離子、退火對其表面形貌、物相、熒光特性、表面成分、透過率、禁帶寬度的影響。實驗結(jié)果說明:真空蒸鍍制備的薄膜表面呈“稻谷”狀,且隨反應(yīng)基底的溫度的上升其表面越發(fā)平整致密,其禁帶寬度呈增大趨勢,然而基底溫度過高又會導(dǎo)致薄膜表面開裂;薄膜呈H(111)面優(yōu)先生長,且隨著襯底溫度的升高衍射峰強度先升后降,200℃時衍射峰最強,薄膜透過率也最高;摻雜Sm3+后,(111)晶面的衍射峰有所下降,而透過率有所上升,其熒光發(fā)射峰變的尖銳且發(fā)射峰強度大幅度提高;隨著退火溫度逐漸上升,薄膜表面越發(fā)粗糙,出現(xiàn)層狀生長的“凸起”,且晶粒尺寸逐漸增大;退火后ZnS:Sm薄膜的衍射峰增強,且向右略有偏移,其透過率顯著下降,禁帶寬度增大。
[Abstract]:ZnS is an important semiconductor substrate with a band gap of 3.59 ~ 3.79e V. it has excellent characteristics and is widely used in various semiconductor components, such as light-emitting diodes, thin film electroluminescent display devices, field luminescent devices, ultraviolet detectors and so on. It can also be used as the n-type window layer of Cu-indium selen-based thin film solar cells. With its unique spectral conversion effect and non-toxicity, the CdS film can be replaced by environmental protection value. The range of spectral response of ZnS can be widened by proper doping (such as Sm,Mn and other impurity atoms). It can also be used as a fluorescent substrate to study its luminescence efficiency. In this paper, microspherical ZnS and ZnS:Sm luminescent materials with regular shape and good dispersion were prepared by solvothermal method using nitrate and sulfur powder as zinc source and sulfur source, samarium oxide as dopant, and filling degree of 75%. The effects of reaction temperature, reaction time, reaction medium and doping molar concentration on the surface morphology, phase structure and fluorescence spectra of the microspheres were discussed. The experimental results show that the higher the reaction temperature, the larger the particle size, the more complete the crystal growth, and the higher the luminescence intensity increases and then decreases with the increase of temperature, and the more the amount of Sm3 is added, the more luminescence centers are generated and the higher the luminescence intensity is. However, when the doping amount of Sm3 reaches 5, the luminescence weakens, and when the reaction medium is ethanol, the agglomeration of the ZnS nanospheres is serious, and the position of the excitation emission peaks are all blue shifted. The optimum reaction conditions are as follows: reaction temperature 170 鈩，

本文編號：2264874