METHOD FOR MANUFACTURING AN N-TYPE MONOCRYSTALLINE SILICON INGOT

摘要

The present invention relates to a method for manufacturing an n-type monocrystalline silicon ingot, with monitored concentration of oxygen-based thermal donors, comprising at least the following steps: (i) providing a bath of molten silicon comprising one or more n-type doping agents, said bath being supplemented at least with germanium (Ge) and/or tin (Sn) with levels that are adapted such as to inhibit the formation of all or part of the thermal donors in the expected silicon ingot; and (ii) drawing the silicon ingot from the bath of step (i) by a Czochralski drawing method, the initial drawing speed V1 being reduced to a speed V2 = V1/b, wherein b is between 10 and 1.2, when the solidified silicon fraction fs reaches a predetermined critical value. The invention also relates to a monocrystalline silicon ingot obtained according to said method and to the use thereof for manufacturing a photovoltaic cell by a low-temperature method.