A Study on the Manufacturing and Characterization of Polysilicon Crystalline Materials

• Main Authors: Wen-Ming Chang, 張文銘
• Other Authors: Shi-yung Chiou
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/44326858017499612835

碩士 === 國立高雄應用科技大學 === 模具工程系 === 98 === This study is to manufacture the polycrystalline silicon ingot. Na2SiF6 is reduced to SiF4 at 650℃ using SRI(Stanford Research Institute)method. SiF6 is reacted with sodium in the reactor to produce the mixed products of polysilicon and sodium fluoride. The mixed P-Si and NaF are then melted at 1600℃ and separated into two liquid layers of P-Si and NaF. The heating temperatures of mixed P-Si and NaF are designed by various heating curves to achieve the different extent of purification of P-Si. The P-Si ingots are characterized by inductively couple plasma optical emission spectrometry (ICP), optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM) and RT testers. The results appear that the main impurity of Fe decreases to 2 ppm while the Na impurity decreases from 5000 ppm to 110 ppm after purification. OM metalligraphs show different extent of oxides in P-Si. The fcc crystal phase without (2 0 0) peak is found to idenfify Si microstructure. The SEM images show the different element distributions. The resistivities are measured to be 0.5 ~ 1.8 Ω•cm and N-type properties of Si are examined by RT-100 Resistivity Tester.