氧化钨二氧化钛复合共生薄膜的拉曼光谱结构研究

采用电子束及真空热蒸发的方式镀制了氧化钨薄膜及掺杂的氧化钨的复合共生薄膜.运用拉曼光谱以及电化学工作站等测试手段分析了氧化钨复合共生薄膜的结构及电致变色性能.通过对拉曼光谱曲线的解叠分峰处理发现,源于晶相的810 cm-1拉曼峰的相对强度变化与样品的致色效率存在负相关,即拉曼峰相对强度越小,样品的致色效率越高.     

金属Al背电极二维AZO光栅的制备和陷光特性

研究了背电极金属Al膜上二维ZnO:Al光栅的制备及其反射光谱特性.在厚度为300 nm的Al膜上溅射80 nm ZnO:Al薄膜,旋涂AZ5206光刻胶,用波长为325 nm的激光进行光刻制作光栅掩模.采用溶脱-剥离法在Al衬底上制备周期(624~1250 nm)和槽深(100~300 nm)可独立调控的ZnO:Al二维光栅.表面形貌采用原子力显微镜和扫描电镜观察,反射光谱用带积分球的分光光度计测试,双向反射分布函数用散射仪测量.结果表明,300 nm Al膜上织构二维ZnO:Al光栅背电极结构,当光栅槽深为228 nm,周期从624 nm增加到986 nm时,背电极总反射率、漫反射率以及雾度均随光栅周期增大而显著增加,而当周期从986 nm增加到1250 nm时,总反射率、漫反射率以及雾度略有增加.双向反射分布函数测试结果进一步证实了上述实验结果,即随着周期增大,漫反射峰值越大,衍射峰个数也增多.提示背反电极上槽深为228 nm、周期为986 nm的二维ZnO:Al光栅具有较好的散射效果,其中漫反射占总反射的百分比为45%.     

复合绒面ZnO:Al光栅增强薄膜硅电池陷光特性

探讨复合绒面ZnO:Al光栅对薄膜硅太阳能电池光俘获效率的影响.织构了由关联长度(lcor)和平均高度(have)表征的绒面,叠加到周期为980nm和槽深为160nm的一维正弦ZnO:Al光栅上,形成复合绒面ZnO:Al光栅.前电极AZO光栅,当lcor较小和have较大时,电池的短路电流较高.若lcor取0.01,则短路电流随have的增大而升高,由have=0.05时的21.93 mA/cm2增加到have=0.80时的23.80mA/cm2.置于背电极且lcor=0.01时,短路电流随have的增加而逐渐减小,由have=0.05时的25.50mA/cm2降到have=0.80时的24.81 mA/cm2.采用直流溅射和化学腐蚀方法分别制备了无绒面ZnO:Al光栅和lcor=0.01,have=0.14的复合绒面ZnO:Al光栅.反射率测试结果表明,复合绒面ZnO:Al光栅总反射率(8.3%)较无绒面ZnO:Al栅(10.2%)降低了1.9%,镜面反射率(4.7%)较无绒面ZnO:Al栅(6.8%)降低了2.1%.以实验制备的两种光栅为模型用严格耦合波方法进行模拟,计算结果表明与无绒面ZnO:Al光栅相比,复合绒面ZnO:Al光栅的总反射率和镜面反射率均显著下降.复合绒面ZnO:Al光栅由于具有较好的减反作用更适合用作薄膜电池前电极,从而得到更高的短路电流;而无绒面ZnO:Al光栅因具有较高的反射适用于背电极,能将到达背电极的光子重新返回硅吸收层而获得更高的陷光效率.     

Multimode resonance bandpass filter with twin wideband channels

A bandpass filter with twin wideband channels in a single-layer guided-mode resonance grating is presented.Strong refractive-index modulation is used to support the excitation of multimode resonances TE1,0,TE1,1,TE2,0,TE1,2,and TE2,1,which are excited by the first and second diffraction orders,relate asymmetrical line shapes and broad low-transmission bands,where TE is the transverse electric.Taking advantage of narrow linewidth and sharp edge line shape in the spectra of TE2,υ(v is the mode),a bandpass filter with form factors of 0.61 and 0.7 for long-and short-wave channels is presented to demonstrate this concept.     

Light trapping enhancement in thin film silicon solar cells with different front and back grating periodicities

Dual-grating structure thin-film silicon solar cells with different front and back grating periodicities are designed The geometrical parameters of both gratings are investigated. The reflection is greatly reduced by the front grating, whereas the absorption in the long wavelength is increased because of the back grating. The short circuit current of the combined structure is enhanced by 16.8% for a 1μm thick c-Si layer compared with that of the conformal grating structure. The short circuit current can be further increased by creating a relative lateral displacement between the front and back gratings. The displacement results in a more remarkably enhaneed absorption when the thickness of the aetive layer is reduced, indicating its importance in the design of ultra-thin high-efficiency solar cells.     

亚微米AZO光栅及其漫透射分布特性

探讨亚微米掺铝氧化锌(AZO)光栅的漫透射光谱特性。在AZO薄膜上涂布光刻胶,用325nm激光双光束干涉曝光得到掩模图案。将其置于质量分数为0.5%的稀盐酸溶液中湿法刻蚀,制备出周期(780～1280nm)和高度(60～300nm)能独立调控的AZO一维光栅。正入射双向透射分布函数(BTDF)测试结果表明,400～900nm波段内平均镜面透射率随光栅周期增大而降低,与紫外-可见分光光度计测得的结果吻合;同时,周期越大被衍射到30°～80°范围内的漫透射比重和漫透射峰值均越大,而峰位角越小。根据光栅方程对实验结果给出了合理的解释。     

Light scattering effect of submicro-textured Ag/Al composite films prepared at lower substrate temperatures

We present a new and practical approach for preparing submicro-textured silver and aluminum (Ag/Al) double-structured layers at low substrate temperatures. The surface texturing of silver and aluminum double-structured layers was performed by increasing the deposition temperature of the Al layers to 270℃. The highly submicro-textured silver and aluminum double-structured layers were prepared by thermal evaporation on quartz glasses and their surface microstructure, light scattering properties, and thermal stability were investigated. Results showed that the highly submicro-textured Ag/Al composite films prepared at low substrate temperatures used as back reflectors not only can enhance the light scattering and have good thermal stability, but also have good adhesion properties. In addition, their fabrication is low cost and readily carried out.     

自支撑聚酰亚胺/锆膜的制备及性能改善

 采用直流磁控溅射法制备自支撑锆(Zr)膜,采用二步法制备聚酰亚胺(PI)膜,在Zr膜表面沉积PI膜得到自支撑PI/Zr复合膜。均苯四甲酸酐(PMDA)和二甲基二苯醚(ODA)在二甲基乙酰胺(DMAC)中反应得到聚酰胺酸(PAA),然后PAA高温亚胺化得到PI;PI成膜时采用提拉法成膜。经国家同步辐射实验室计量线站测定,实际测量结果与理论分析一致,PI膜的引入虽然会导致自支撑薄膜透过率有所下降,但在类镍-银软X射线13.9 nm波段PI(200 nm)/Zr(300 nm)和PI(200 nm)/Zr(400 nm)自支撑薄膜的透过率仍然分别达到14.9%和7.5%。     

湿法和溶脱法的亚微米ZnO:Al光栅制备

以激光干涉法得到的光刻胶图案为掩模,采用湿法刻蚀和溶脱-剥离法制备了具有良好减反射特性的亚微米掺铝氧化锌（ZnO:Al, AZO）光栅。表面形貌特征和反射光谱测试结果表明,湿法刻蚀较溶脱-剥离法得到的AZO光栅表面更为粗糙,两者均方根粗糙度分别为25.4,7.6 nm。在400～900 nm波段,两种方法制备的周期和高度相同的光栅,平均总反射率分别由AZO薄膜的12.5%下降到8.3%和10.2%。两者的平均镜面反射率分别为6.2%和6.6%,平均漫反射率分别为2.1%和3.6%。湿法刻蚀得到的表面较为粗糙AZO光栅的漫反射明显减弱,从而导致总的减反特性优于溶脱-剥离法得到的表面起伏相对较小的AZO光栅。     

Scattering properties of ZnO gratings on A1 back reflectors for thin film silicon solar cells

Light scattering properties of back grating structures that composed of one-dimensional ZnO gratings and a flat 300-nm A1 reflectors are investigated. Results show that grating structures cause an 8% reduction of the total reflectivity, as grating periods increasing from 620 to 1435 nm, both the diffuse reflectivity and the haze parameter enhance drastically between 400 and 1 000 nm, whereas the diffraction angle at normal incidence reduce greatly, which agree with the values calculated from grating equation. It is concluded that rear gratings have the potential of scattering a substantial amount of incident light to specific angles and enlarging the optical path.