A New Technique for Antimony Diffusion into Silicon

A new technique using auxiliary silicon wafers lapped with Al 2 O 3 powder has been developed for Sb diffusion into silicon. Diffusion wafers are set face to face with those wafers in an open‐tube system with Sb 2 O 3 as the dopant source. This technique can easily attain a carrier concentration as high as the solid solubility of Sb in silicon without surface defects such as surface erosion. Carrier concentration is controlled by changing the distance between the diffusion and auxiliary wafers. In addition, it is confirmed that higher diffused areas on the diffusion wafers correspond to the lapped areas of the auxiliary wafers.