DOPANT FUNNEL FOR LOADING AND DISPENSING DOPANT
A dopant funnel for loading dopant pellets into a dispenser tube of a dopant dispenser is disclosed. The dopant funnel has a cup connected through a restrictor to a shaft. The cup holds random oriented dopant pellets. The restrictor meters the amount and orientation of dopant pellets being removed from the cup. The shaft is in alignment with the restrictor for delivering dopant pellets from the cup to the dispenser tube.
1 . A dopant funnel for loading dopant pellets into a dispenser tube of a dopant dispenser, the dopant funnel comprising:
a cup for holding the dopant pellets, the cup having a restrictor to meter the number of dopant pellets exiting the cup;
a shaft in alignment with the restrictor for delivering the dopant pellets from the cup to the dispenser tube.
2 . The dopant funnel of claim 1 , further comprising a delivery tube connected with the shaft for aligning the shaft with the dispenser tube.
3 . The dopant funnel of claim 2 , wherein the delivery tube includes a passage terminating in an orifice sized to receive the dispenser tube therein.
4 . The dopant funnel of claim 1 , wherein the shaft includes a trough aligned with the passage through the delivery tube.
5 . The dopant funnel of claim 4 , wherein the trough includes a length and a bottom for supporting the dopant pellets as the dopant pellets move along the length of the trough, the bottom of the trough includes a slot to extract broken pellets as the dopant pellets move along the length of the trough.
6 . The dopant funnel of claim 5 , wherein the slot has a slot length that is less than one pellet length.
7 . The dopant funnel of claim 5 , wherein the slot has a slot width that is more than one pellet diameter to allow the broken pellets to be extracted through the slot.
8 . The dopant funnel of claim 1 , wherein the shaft includes a length, a bottom for supporting the dopant pellets as the dopant pellets move along the length of the shaft, and a baffle for aligning the dopant pellets as the dopant pellets move along the length of the shaft.
9 . The dopant funnel of claim 8 , wherein the baffle terminates at a distance from the bottom of the shaft equal to approximately one pellet diameter to prevent unaligned dopant pellets from moving past the baffle.
10 . The dopant funnel of claim 1 , wherein the shaft includes a plurality of baffles, wherein at least two of said baffles are disposed opposite one another.
11 . The dopant funnel of claim 1 , further comprising a vibrator for causing movement of the dopant pellets with respect to the dopant funnel.
12 . The dopant funnel of claim 11 , wherein a baffle is disposed along the shaft for alignment of the dopant pellets and the vibrator is located adjacent to one of the restrictor and the baffle.
13 . A method for loading a dispenser tube of a dopant dispenser for use in a crystal pulling system with a dopant funnel having a cup connected through a restrictor with a shaft, the method comprising:
loading the cup of the dopant funnel with randomly oriented dopant pellets;
aligning the shaft with the dispenser tube; and
causing a vibrating movement of the dopant funnel to induce movement of the randomly oriented dopant pellets with respect to the dopant funnel.
14 . The method of claim 13 , wherein the vibrating movement is provided by a vibrator connected to the dopant funnel.
15 . The method of claim 14 , wherein causing a vibrating movement includes activating the vibrator.
16 . The method of claim 13 , wherein the shaft includes a length and a baffle for aligning the randomly oriented dopant pellets as the dopant pellets move along the length of the shaft.
17 . The method of claim 16 , wherein the shaft includes a vibrator located adjacent to the baffle.
18 . The method of claim 13 , wherein the vibrating movement align pellets with the restrictor to allow the pellets to move out of the cup.
19 . The method of claim 13 , wherein the shaft includes a slot for extracting broken pellets from the dopant funnel.
20 . The method of claim 13 , wherein the loading of the cup includes loading the cup with dopant pellets having a specific unbroken size, including a standard pellet width and standard pellet length.