US5365094A
Expired / Lapsed
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Semiconductor device including ferroelectric nonvolatile memory
Assignee: Rohm Co Ltd
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Filing: 1992-11-12
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Granted: 1994-11-15
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Expires: 2012-11-12
Abstract
Abstract The present invention provides a ferroelectric nonvolatile memory that utilizes ferroelectric properties and is able to operate correctly at lower voltage. A memory storage cell of the memory has the structure wherein a N+ type drain (24) and a N+ type source (26) is provided for a P type well (14) created in the substrate. A film (22) of high dielectric material spans the space (28) between the drain (24) and the source (26). A conductive metalization (20) overlies the film (22), a film (18) of ferroelectric material overlies the conductive metalization (20) and a metalization 16 overlies the film (18).
Inventors
- 👤 Hidemi Takasu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:04
CPC Classifications
H; H10; H10B; H10B53/00; H10D; H10D30/00; H10D30/60; H10D30/69; H10D30/701; H10D30/68
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
84 words
A semiconductor device including ferroelectric nonvolatile memory utilizing dielectric polarization comprising: a first conductivity type semiconductor region; a pair of second conductivity type diffusion regions formed in the first conductivity type semiconductor region and defining a space between the pair of diffusion regions; an insulating layer of a material having a dielectric constant magnitudes higher than that of silicon nitride spanning the space between the pair of diffusion regions; a ferroelectric layer overlying the insulating layer; and a control electrode overlying the ferroelectric layer.
Claim 2
Dependent Claim
84 words
A semiconductor device including ferroelectric nonvolatile memory utilizing dielectric polarization comprising: a first conductivity type semiconductor region; a pair of second conductivity type diffusion regions formed in the first conductivity type semiconductor region and defining a space between the pair of diffusion regions; an insulating layer of a material having a dielectric constant magnitudes higher than that of silicon nitride spanning the space between the pair of diffusion regions; a ferroelectric layer overlying the insulating layer; and a control electrode overlying the ferroelectric layer.
Claim 3
Dependent Claim
56 words
A semiconductor device including ferroelectric nonvolatile memory according to claim 1, wherein the pair of second conductive type diffusion regions consists of a source layer and a drain layer, so that a conductive channel may be created between the source layer and the drain layer in some circumstances by applying a voltage to the control electrode.
Claim 4
Dependent Claim
33 words
A semiconductor device including nonvolatile memory according to claim 2, wherein the insulating layer is made from a high dielectric material selected from the group consisting of SrTiO 3 and PbZrO 3 .
Claim 5
Dependent Claim
99 words
A semiconductor device including ferroelectric nonvolatile memory utilizing dielectric polarization comprising: a first conductivity type semiconductor region; a pair of second conductivity type diffusion regions formed in the first conductivity type semiconductor region and defining a space between the pair of diffusion regions; an insulating layer of SrTiO 3 spanning the space between the pair of diffusion regions; a refractory metal conducting layer having aligned dipole moments, which layer is overlying the insulating layer; a ferroelectric layer overlying said conducting layer; said conducting layer increasing the alignability of said ferroelectric layer; and, a control electrode overlying the ferroelectric layer.
Claim 6
Dependent Claim
99 words
A semiconductor device including ferroelectric nonvolatile memory utilizing dielectric polarization comprising: a first conductivity type semiconductor region; a pair of second conductivity type diffusion regions formed in the first conductivity type semiconductor region and defining a space between the pair of diffusion regions; an insulating layer of SrTiO 3 spanning the space between the pair of diffusion regions; a refractory metal conducting layer having aligned dipole moments, which layer is overlying the insulating layer; a ferroelectric layer overlying said conducting layer; said conducting layer increasing the alignability of said ferroelectric layer; and, a control electrode overlying the ferroelectric layer.
Claim 7
Dependent Claim
56 words
A semiconductor device including ferroelectric nonvolatile memory according to claim 4, wherein the pair of second conductive type diffusion regions consists of a source layer and a drain layer, so that a conductive channel may be created between the source layer and the drain layer in some circumstances by applying a voltage to the control electrode.
Claim 8
Dependent Claim
30 words
A semiconductor device including nonvolatile memory according to claim 5, wherein the insulating layer is made from a material having a dielectric constant magnitudes higher than that of silicon nitride.
Claim 9
Dependent Claim
33 words
A semiconductor device including nonvolatile memory according to claim 5, wherein the conducting layer is made from a refractory metal selected from the group consisting of Platinum, Molybdenum, Titanium, Tungsten, Tantalum and Nickel.
References Cited (Backward Citations)
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