水浴法製備In2S3奈米結構在p-Si異質接合太陽能電池之研究

Study of In2S3 Nanostructures by Chemical Bath Deposition for p-Si Heterojunction Solar Cells

陳彥龍(Yan-Lung Chen)

指導教授 ： 姬梁文

共同指導教授 ： 蕭育仁(Yu-Jen Hsiao)

國立虎尾科技大學/電機資訊學院/光電與材料科技研究所/碩士(2011年)

摘要

本論文主要分為三個部分：第一部分探討β-In2S3的微米絨球結構之螢光粉末與奈米柱結構之薄膜光學特性和表面形貌 ；第二部分利用非等向性濕蝕刻，製作金字塔結構提高抗反射率。第三部分製備新穎的AZO/In2S3/p-Si異質結構太陽能電池。
第一部份：使用低溫度水浴法技術製作β-In2S3薄膜與粉末。一般來說，材料的表面形貌會影響光學和物理特性。這微米絨球結構的β-In2S3粉末使用穿透式電子顯微鏡觀察出絨球直徑約在1到2μm左右。In2S3的銦與硫成分組成比44：56接近符合化學劑量比藉由ESD的量測數據。這晶相圖和繞射圖得知In2S3微米絨球屬於多晶結構。同時擁有具有立方和四方的新穎的雙重相位β-In2S3是藉由XRD來分析判斷。β-In2S3近能帶邊界的發散在592nm展現出具有橙色螢光特色。由頻譜圖（dR/dλ versus λ）得知β-In2S3能隙是2.06 eV.
另一方面，從SEM圖觀察出In2S3薄膜呈現奈米柱結構。利用XRD、FESEM、AFM、PL和紫外光吸收光譜來探討表面形態與光學特性。
第二部分：利用溼式蝕刻在矽基板表面製作金字塔結構。金字塔結構主要目的增加光的吸收，產生更多的電子-電洞對，能夠增加短路電流密度。良好的實驗參數能獲得品質較佳的金字塔結構。在相對較低濃度的溶液、低溫度、所得到結果將會導致金字塔結構有鈍化現象。
第三部分：製備新穎的AZO/In2S3/p-Si異質結構太陽能電池。首先，使用溼蝕刻將矽基板製作成金字塔結構。並使用低溫度水浴法合成In2S3薄膜在糙化的矽基板，然後使用射頻濺鍍AZO薄膜在In2S3薄膜。背電極使用鋁漿旋塗在矽基板背面。糙化的矽基板能夠提高光吸收，並增加短路電流密度。

關鍵字

微米絨球 ； 非等向性濕蝕刻 ； 糙化結構 ； 異質結構 ； 太陽能電池

並列摘要

The article mainly consists of three items. Part I, we reported the surface morphology and the optical properties of β-In2S3 mircopompons phosphors and nanorods of In2S3 thin films, respectively. Part II, textured structures can improve the antireflection by wet anisotropic etching. Part III, a novel AZO/In2S3/p-Si hetero-junction solar cell was fabricated.
Part I : Nanorods of β-In2S3 thin films and micro-pompons of β-In2S3 phosphors were prepared by chemical bath deposition (CBD) technique at lower temperature. In general, the surface morphology of the material can affect the optical and physical properties depend on the different synthesis technology. Mircopompons of β-In2S3 phosphors with TEM indicated the pompon with diameter in the range from 1 to 2 μm. The EDS data indicated that the composition of indium and sulfur with the In/S ratio of 44:56 which had been close to the stoichiometry of In2S3 compound. The lattice image and the diffraction pattern revealed the polycrystalline of In2S3 mircopompons. XRD showed both cubic and tetragonal of novel double-phases of β-In2S3. PL spectra indicated the near-band-edge (NBE) emission at 592 nm. Furthermore, the NBE emission was corresponded to orange luminescence. The band gap of β-In2S3 phosphors indicated at 2.06 eV (600 nm) from spectra (dR/dλ versus λ ) of the reflectance traces.
On the other hand, nanorod structures of In2S3 thin films were shown by these SEM images. These In2S3 thin films were characterized by X-ray diffractometer, field-emission scanning electronic microscope (FESEM), atomic force microscopy (AFM), photoluminescence (PL) and UV-Vis spectrometry.
Part II : pyramid structures were forms the surface silicon using wet etching. Pyramid structures main function to increase the absorption of light, generate more electron-hole pairs, lead to higher short current density. Good experimental parameters can obtain the most structure. The passivation structure can be changed on other parameters such as the relatively low concentration of solution, the lower temperature.
Part III : a novel AZO/In2S3/p-Si hetero-junction solar cell was fabricated. First, the textured structure of single-crystal silicon (100) was formed by the wet-chemical etching in the solution. Sequentially, In2S3 thin film was synthesized on the textured silicon substrate by chemical bath deposition (CBD) at lower temperature. Then, AZO thin film was deposited by RF sputtering deposition. The aluminum paste was prepared by spin-coated on the back surface. Textured silicon substrates can provide high absorption of light and increase short current density.

並列關鍵字

micropompons ； wet anisotropic etching ； textured substrate ； hetero-junction ； solor cell

參考文獻

[1].Markvart T., 1995, Solar Electricity., New York: John Wiley & Sons Pubilication.

[3].J. Salzman, C., et al, 1999, Phys. Status Solidi A, 176, 683.

[4].Shalish, L., et al, 2000, Phys. Rev. B, 61, 15573.

[5].G. Blatter and F. Greuter, 1986, Phys. Rev. B, 33, 3952.

[9].R. N. Bhattacharya and J. Keane, 1984, J. Electrochem. Soc, 143,854.