Impurity diffusion manner null of film and its creation manner and semiconductor substrate for diffusion

摘要

PROBLEM TO BE SOLVED: To enable impurities to diffuse to a number of wafers which are in a state of lamination, by permitting a diffusion film to have an inorganic compound powder of a specific particle diameter as a base substance, and permitting the film to contain an impurity compound and a simple substance of a metal impurity element which are sources of impurity diffusion. ;SOLUTION: A boron diffusion film 10 comprises a boron compound which has SiC powder 11 as a base substance, and a simple substance of aluminum. The simple substance of aluminum may be contained at a concentration of 1 ppm or less, or desirably, none. The particle size of the SiC powder ranges approximately 5-30 μm, that is, the SiC powder has a particle-size distribution close to logarithmic normal distribution, being regulated so that the difference between a value corresponding to 16% accumulation and a value corresponding to 84% accumulation of the particle-size distribution does not exceed 20 μm. For instance, in this case, particle size of SiC powder is properly arranged so as to be mostly distributed within a range of 7-20 μm.;COPYRIGHT: (C)1999,JPO