Texas Instruments Incorporated
Transistor having double isolation with one floating isolation

Abstract:

A semiconductor device includes at least a first transistor including at least a second level metal layer (second metal layer) above a first level metal layer coupled by a source contact to a source region doped with a first dopant type. The second level metal layer is coupled by a drain contact to a drain region doped with the first dopant type. A gate stack is between the source region and drain region having the second level metal layer coupled by a contact thereto. The second level metal layer is coupled by a contact to a first isolation region doped with the second dopant type. The source region and drain region are within the first isolation region. A second isolation region doped with the first dopant type encloses the first isolation region, and is not coupled to the second level metal layer so that it electrically floats.