Semiconductor integrated circuit device having an electrostatic discharge protection circuit and method of manufacturing the semiconductor integrated circuit device

A semiconductor integrated circuit device comprising:

• a P type semiconductor substrate including a P type epitaxial layer;
• an N well formed in the epitaxial layer, the N well including a base having an N type impurity region and an emitter having a P type impurity region;
• a collector formed in the P type epitaxial layer and spaced apart from the N well, the collector having a P type impurity region;
• isolation layers formed for isolating the emitter, the base, and the collector from each other;
• a body contact region formed under the collector;
• and
• an N type blocking well configured to make contact with low surfaces of the isolation layers and surround a sidewall of the body contact region,
• wherein the blocking well detours an electrostatic charge from the emitter toward the body contact region through the semiconductor substrate instead of through the N well.

A method of manufacturing a semiconductor integrated circuit device, the method comprising:

• providing a semiconductor substrate having a first conductive type;
• forming a body contact region in the semiconductor substrate, the body contact region having the first conductive type;
• forming isolation layers in the semiconductor substrate;
• forming an active well having a second conductive type in the semiconductor substrate and forming a blocking well having the second conductive type at a side of the body contact region, the active well spaced apart from the body contact region;
• and
• forming a base and an emitter in the active well between the isolation layers and forming a collector in the body contact region.