Method of fabricating a device with a concentration gradient and the corresponding device

摘要

A semiconductive device is fabricated by forming, within a semiconductive substrate, at least one continuous region formed of a material having a non-uniform composition in a direction substantially perpendicular to the thickness of the substrate.

主权项

1. A method, comprising:
forming a trench in a layer of a first material above an etch stop layer and a substrate; filling the trench with an alloy material comprising a combination of the first material and a second material, the second material being present in the alloy material with a heavier concentration than the first material; and performing heat drive-in to stimulate lateral diffusion of the second material from the alloy material filling the trench and into the first material in the layer within which the trench is formed so as to form a non-uniform composition in a direction substantially perpendicular to a depth of the trench.