Method for making diffusions into a substrate and electrical connections thereto using rare earth boride materials

摘要

A method for diffusing a conductively determining impurity in a semiconductor substrate and making electrical contact thereto by depositing a layer of a rare earth boride material over a predetermined surface portion of the substrate and heating the substrate for a predetermined period of time at a predetermined temperature which is sufficient to cause boron from the boride material to diffuse into the adjoining portion of the substrate to modify its conductive characteristics. At the same time a good electrical ohmic contact is established between the boride material and the adjoining substrate portion while the boride material retains its conductivity even after the outdiffusion of some of its boron into the substrate during the heat treatment.