Patent ID: 11869971
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Computer technology (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 8:
9. A ferroelectric field-effect transistor (FeFET) configured as a 2-bit storage device, the FeFET comprising:
a semiconductor substrate including:
a source region in the semiconductor substrate; and
a drain region in the semiconductor substrate;
a gate stack over the semiconductor substrate, with the source region and the drain region extending to opposite sides of the gate stack, the gate stack including:
a ferroelectric layer over the semiconductor substrate;
a gate region over the ferroelectric layer; and

wherein:
first and second ends of the ferroelectric layer are proximal correspondingly to the source and drain regions; and
the ferroelectric layer includes dipoles; and
a first set of dipoles at the first end of the ferroelectric layer has a first polarization; and
a second set of dipoles at the second end of the ferroelectric layer has a second polarization, the second polarization being substantially opposite of the first polarization;
the first and second polarizations of the corresponding first and second sets of dipoles represent storage of 2 bits;
a first bit of the 2-bit storage device being configured to be read by application of a read voltage to the source region and a do-not-disturb voltage to the drain region; and
a second bit of the 2-bit storage device being configured to be read by application of the do-not-disturb voltage to the source region and the read voltage to the drain region; and
an invertible region extending through the semiconductor substrate between the source region and the drain region.