A study on boron distributions in 12-in boron-doped Cz-Si wafers by neutron-induced storadiography

摘要

Many silicon wafer manufacturers have tried to enlarge a dimension of silicon wafer for productivity enhancement since 1995. As a result, a wafer size of 12-in diameter has been produced. Concerning that, it would be valuable to study a boron distribution on such a dimension wafer. Therefore, we have measured the boron distribution pattern and relative concentrations as a function of location on the wafer by using a method of neutron-induced autoradiography. This work presents a qualitative distribution image and relatively alchemistic concentration of boron according to the locations on the two different Czochralski Silicon (Cz-Si) wafers with different concentration: One is a heavily doped with an order of about 19, and another is a normally doped with an order of 15.