本研究係利用注漿成型法(Slip casting)之製程,進行未添加分散劑(固含量46 vol%)與添加檸檬酸分散劑(固含量53 vol%)之太陽能電池鑄造用二氧化矽石英坩堝燒結性質之研究。在未添加分散劑之二氧化矽粉體漿料,經過球磨後pH值由最初的4.6降為3.8,脫膜後之胚體透過1250~1450°C之不同的燒結溫度,分別進行1、2以及4小時不同燒結時間,經過球磨後pH值由最初的4.6降為3.8,其體密度以及結晶相,接近於太陽能電池鑄造用二氧化矽石英坩堝之規格(體密度大於1.95 g/立方公分、結晶度小於1%),但是孔隙度為15~22%,不能達到石英坩堝小於12%之規格,無法達到太陽能電池鑄造用石英坩堝的要求。添加檸檬酸分散劑之二氧化矽胚體燒結,不同含量之檸檬酸分散劑0.3wt%、0.5wt%與0.8wt%,在1150~1350°C之不同燒結溫度與燒結時間4小時下,可達到接近於太陽能電池鑄造用二氧化矽石英坩堝之規格,其中以檸檬酸分散劑0.3~0.5wt%、燒結溫度1250~1300℃、燒結時間4小時之條件下,較為適合應用於太陽能電池鑄造用二氧化矽石英坩鍋之規格,而添加檸檬酸分散劑更有助於燒結體的緻密性。
Study on manufacture of silica quartz crucible for solar cell casting was investigated by slip casting in two different methods without dispersant (solid content 46 vol%) and citric acid dispersant (solid-content 53 vol%). After milling, the pH value of SiO2 powder slurry was decreased from 4.6 to 3.8. The SiO2 samples after demolding were sintered without dispersant at 1250~1450°C sintering temperature and at 1, 2 and 4 hours sintering time, respectively. The bulk density and crystal phase closed to the specifications of silica quartz crucible for solar cell casting (bulk density>1.95 g/cm^3, crystal phase<1%), but 15~22% porosity was not to meet the specifications of silica quartz crucible for solar cell casting (porosity<12%). The SiO2 samples added 0.3 wt%, 0.5 wt% and 0.8 wt% citric acid dispersant at 1150~1350℃ and 4 hours sintering time closed to the specifications of silica quartz crucible for solar cell casting. All samples with citric acid dispersant 0.3~0.5 wt% at 1250~1300℃ sintering temperature and 4 hours sintering time were suitable for processes of silica quartz crucible for solar cell casting. However, quartz crucibles with citric acid dispersant were enhanced the denseness of sintered samples.