矽塊材在室溫下是高熱導率的材料，約150W/m*K，也因此純矽塊材為不良的熱電材料。為了提升熱電性質，球磨並添加摻雜元素是常見的方法，利用界面散射使熱導率下降，以摻雜提升電導率。 本研究將矽顆粒和不同比例的鋁顆粒一起球磨，研磨24小時後利用火花電漿燒結成塊材，燒結時最高溫度約1000°C，低於矽燒結時常使用的溫度，藉鋁熔化後幫助顆粒之間的連接和提升矽的結晶性而可以讓燒結溫度降低到1000°C。燒結後的塊材進行熱電性質量測，溫度範圍為室溫至450°C，得知當鋁添加量是5at%以上時，導電率明顯提升，顯示添加5at%以上的鋁有顯著的摻雜效果，並得知添加5at%鋁有最好的熱電性質。 ;The thermal conductivity of bulk silicon is 150 W/m*K at room temperature. It is considered as poor thermoelectric materials. Ball milling with doping is a common method for enhancing thermoelectric efficient. In our study, silicon and aluminum particles were milled in a ball mill bar with different ratio for 24 hours. After milling, the milled particles were fabricated into bulk samples via spark plasma sintering. The sintering temperature was 1000°C, which was lower than that often used in the sintering of silicon. The reason for the lower sintering temperature is that the molten aluminum can help the connection of silicon particles and enhance the crystallinity. After sintering, we measured the thermoelectric properties of bulk sintered sample from room temperature to 450°C. We found that the electrical conductivity was significantly improved when the aluminum exceeds 5at%. The result shows that addition of more than 5at% aluminum has significant doping effect and we found that the sintered bulk sample has the improved thermoelectric properties with the addition of aluminum of 5at%.
