A doping system for introducing liquid dopant into a melt of semiconductor or solar-grade material includes a dopant reservoir for holding dopant and a feeding tube. The dopant reservoir includes a body and a tapered end defining an opening having a smaller cross-sectional area than a cross-sectional area of the body. The feeding tube includes a first end extending from the opening of the reservoir, a second end distal from the first end, an angled tip disposed at the second end of the feeding tube, a first restriction for inhibiting the passage of solid dopant through the feeding tube, and a second restriction for controlling the flow of liquid dopant, the second restriction disposed near the second end of the feeding tube.