New donor generation in p-type CZ Si commonly used for LSI manufacture after annealing at 700℃ has been studied. This new donor is confirmed to be closely correlated with oxygen impurity as is the thermal donor formed in 450℃ annealing. However

the new donor differs greatly in annealing behavior from the thermal donor. The generation rate of new donor is slower than that of thermal donor

and the maximum new donor concentration after annealing for a long duration （100 hrs.） is about 1015 cm-3. Impurity carbon promotes the generation of new donor. The mechanism of the new donor generation has been also briefly discussed.