Method of growing single crystal silicon by the Czochralski method which eliminates the need for post growth annealing for resistivity stabilization

摘要

This disclosure relates to a technique of improving the quality of crystals grown by the Czochralski method by substantially eliminating the formation of electrically active oxygen complexes during growth. The oxygen which forms these complexes is liberated from the quartz liner which contains the silicon melt. It has been found that electrically active oxygen complexes (oxygen donors) are formed in the silicon lattice during crystal growth when the crystal is in the range of 300-500 DEG C. Above and below this temperature range, the formation of oxygen donors in the silicon lattice is minimal. The crystal is therefore maintained in its entirety above the temperature of 500 DEG C. and then is quenched to be quickly brought below the 300 DEG C. level. In this way, the silicon crystal is in the 300 DEG C. to 500 DEG C. range for a minimal period of time, thereby minimizing the amount of oxygen donor formation in the silicon lattice during growth. The quenching can take place along the entire rod after it has been pulled, or it can take place on a zone basis along the rod after it is moved away from the melt.