LATCHUP REDUCTION BY GROWN ORTHOGONAL SUBSTRATES

摘要

An integrated circuit is formed by providing a heavily doped substrate of a first conductivity type, forming a lightly doped lower epitaxial layer of the first conductivity type over the substrate, implanting dopants of the first conductivity type into the lower epitaxial layer in an area for a shallow component and blocking the dopants from an area for a deep component, forming a lightly doped upper epitaxial layer over the lower epitaxial layer and activating the implanted dopants to form a heavily doped region. The shallow component is formed over the heavily doped region, and the deep component is formed outside the heavily doped region, extending through the upper epitaxial layer into the lower epitaxial layer.

主权项

1. An integrated circuit, comprising:
a substrate of a first conductivity type, having a bulk resistivity less than 1 ohm-cm; a lower epitaxial layer having said first conductivity type disposed over said substrate, said lower conductivity layer having a bulk resistivity above 1 ohm-cm; an upper epitaxial layer having said first conductivity type disposed over said lower epitaxial layer, said upper conductivity layer having a bulk resistivity above 1 ohm-cm; a doped region having said first conductivity type disposed in said lower epitaxial layer, extending at least up to a top of said lower epitaxial layer and at least down to a bottom of said lower epitaxial layer, said doped region having a bulk resistivity less than 1 ohm-cm; a shallow component disposed in said upper epitaxial layer above said doped region; and a deep component disposed in said upper epitaxial layer and said lower epitaxial layer, outside of said doped region.