陶瓷基板上披覆高黏度，低熱膨脹性玻璃陶瓷之研究

Coating of high viscosity, low thermal expansion glass-ceramic on ceramic substrates

林孟姍(Meng-shan Lin)

指導教授 ： 徐錦志

大同大學/工程學院/材料工程學系所/碩士(2010年)

摘要

利用異質基板披覆玻璃層取代矽晶片應用於薄膜太陽能電池中，以降低模組成本。但沉積矽晶於異質基板上，常因矽晶粒細小，矽晶優選方向差和雜質的擴散，影響電性。選擇在陶瓷基板上披覆MgO–ZnO- Al2O3-SiO2-TiO2-ZrO2玻璃陶瓷層，以提供較小的表面粗糙度和較佳的熱機械性質。結果顯示：玻璃層經熱處理後，表面和內部之結晶相相同：玻璃陶瓷層經一階段熱處理後，主要含有ZrSiO4相，且表面結晶具有優選方向 <200>。經二階段熱處理後，主要生成β-quartz s.s.、spinel s.s.和t-ZrO2。額外增加810°C / 4h (三階段熱處理)，會抑制β-quartz s.s.生成。熱處理後玻璃陶瓷表面粗糙度Rq為二階段>三階段>一階段熱處理，且隨起始溫度越高，多階段熱處理對表面粗糙度的影響越小。玻璃層經三階段熱處理，玻璃轉移溫度可達1010°C，而300~800°C之熱膨脹係數(CTE)約 51 × 10-7 K-1。熱膨脹係數匹配陶瓷基板和矽晶層。
低溫濺鍍非晶矽於玻璃陶瓷層上，再進行結晶熱處理。矽晶粒徑隨結晶熱處理溫度上升而變大，1100°C / 6h，矽晶粒徑約33 nm。研究發現，固定矽膜結晶熱處理溫度，隨玻璃層熱處理之階段數越多，矽晶粒徑越小，可能細化之晶粒提供許多異質成核點所造成。

關鍵字

尖晶石 ； 薄膜太陽能電池 ； 玻璃陶瓷

並列摘要

Solar modules made from thin - film crystalline - silicon layers on low - manufacturing cost substrates could decrease the cost of photovoltaic electricity if sufficiently high efficiencies could be reached. The main factors that affect the efficiency of solar modules are grain size and the preferred orientation of c-Si thin-film, which depends on the surface roughness of substrates and methods of depositing silicon film.

In this work, spinel glass-ceramic produced from compositions of SiO2-Al2O3-ZnO-MgO-TiO2-ZrO2 system is used as a buffer layer between ceramic substrate and silicon thin - film. The glass - ceramic possess thermal expansion coefficients (CTE) of 30-52 × 10-7 K-1, which matches the CTE of both silicon and ceramic substrate. As the results, the surface roughness (Rq=0.8 nm) of glass-ceramic made by a two-stage heat treatment is smaller than that made by a single stage (Rq=3.1 nm). Besides, The glass transition temperature (Tg) of residual glass could be up to 1037 °C by a two – stage heat treatment.

The crystallization of amorphous silicon films deposited by RF magnetron sputtering on buffer layers is studied by thermal annealing in the temperature range between 750 °C and 1200 °C for epitaxial growth. The epitaxy was carried out using a tube conventional furnace. And X-ray diffraction technique was used to determine the preferential orientation and grain size of the c-Si thin-film. The preferential orientation is <220> for all heat treatment temperature. And the grain size is increased by the increment of annealing temperature.

並列關鍵字

solar cell ； thin film ； glass-ceramic ； spinel

參考文獻

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