METHOD FOR FORMING DIFFUSIONS HAVING NARROW DIMENSIONS

摘要

METHOD FOR FORMING DIFFUSIONS HAVING NARROW DIMENSIONS A method for forming diffusions having narrow, for example, submicrometer dimensions in a silicon body which involves forming insulator regions on a silicon body, which insulator regions have substantially horizontal surfaces and substantially vertical surfaces. A layer having a desired dopant concentration is formed thereon, both on the substantially horizontal surfaces and the substantially vertical surfaces. Reactive ion etching of the layer acts to substantially remove only the horizontal layer and provides a narrow dimensioned layer having a desired dopant concentration in the substantially vertical surfaces. Heating of the body at a suitable temperature is accomplished so as to produce the movement of the dopant into the silicon body by diffusion to form diffusions having narrow, such as submicrometer dimensions, therein. FI9-78-024