US 6,445,043 B1 · Isolated regions in an integrated circuit

Abstract

A process for forming isolated active device regions on a silicon substrate comprises the steps of forming at least one trench in a silicon substrate to define at least two active device regions on the substrate to be isolated from each other, depositing an electrically insulative material on the substrate to fill the trench with the material, planarizing the surface of the substrate, performing a masking and etching operation to expose at least one active device region on the substrate, selectively growing a first epitaxial layer of silicon on the exposed active device region, masking the substrate to leave exposed at least one other active device region on the substrate, selectively growing a second epitaxial layer of silicon on the other exposed active device region, the first epitaxial layer and second epitaxial layer being doped with dopant atoms to the same or different dopant concentration to provide, at least two isolated active device regions on the silicon substrate. The process of the invention enables the fabrication of performance optimized MOS-type and bipolar devices simultaneously and independently of each other on a single clip or wafer.

Claims20

Dependent claims

A semiconductor integrated circuit produced by the steps of:

a) forming at least one trench in a silicon substrate to define first and second active device regions on the substrate to be isolated from each other;
b) depositing an electrically insulative material on the substrate to fill the trench with the electrically insulative material, said electrically insulative material having a top surface;
c) planarizing a top surface of the substrate such that the top surface of the substrate in the first and second active device regions is coplanar with the top surface of the electrically insulative material of the filled trench;
d) selectively growing a first epitaxial layer of silicon on top of and in contact with the top surface of the first active device region;
e) selectively growing a second epitaxial layer of silicon on the top surface of the second active device region, the first epitaxial layer and second epitaxial layer being doped with dopant atoms to the same or different dopant concentration, to provide at least two isolated active device regions on the silicon substrate;
f) forming a bipolar transistor on the first epitaxial layer;
and
g) forming a complementary metal oxide semiconductor (CMOS) device on the second epitaxial layer.

5 more elements

Dependencies are inferred from the claim text.

Isolated regions in an integrated circuit

Life of this patent

Isolated regions in an integrated circuit

Life of this patent

Abstract

Claims20