EP0152689A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Memory device
Assignee: BP PLC
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Filing: 1984-12-06
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Granted: —
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Expires: 2004-12-06
Abstract
Abstract A method of determining the conductance state of a non-volatile memory device switchable between high and low conductance states is provided. The device comprises at least one p-type amorphous or microcrystalline semiconductor and an n or i-type layer. The device is irradiated with light to produce a photovoltaic response which is used to determine the conductance state.
Inventors
- 👤 Peter John Hockley
- 👤 Michael John Thwaites
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 10:55
CPC Classifications
G; G11; G11C; G11C7/00; G11C7/005
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
91 words
A process for detecting the conductance state of a non-volatile memory device which is switchable between a high conductance and a low conductance state and which comprises a plurality of amorphous or microcrystalline semiconductor layers at least one of which is a p-type layer in contact with an n or i-type layer, characterised by irradiating the device with light of a wavelength which causes band to band excitation and of an intensity which produces a detectable photovoltaic response and using the photovoltaic response to determine the conductance state of the device.
Claim 2
Dependent Claim
91 words
A process for detecting the conductance state of a non-volatile memory device which is switchable between a high conductance and a low conductance state and which comprises a plurality of amorphous or microcrystalline semiconductor layers at least one of which is a p-type layer in contact with an n or i-type layer, characterised by irradiating the device with light of a wavelength which causes band to band excitation and of an intensity which produces a detectable photovoltaic response and using the photovoltaic response to determine the conductance state of the device.
Claim 3
Dependent Claim
21 words
A process according to claim 1 wherein the semiconductor material consists essentially of elements of Group IV of the Periodic Table.
Claim 4
Dependent Claim
15 words
A process according to claim 2 wherein the semiconductor material is silicon and/or silicon carbide.
Claim 5
Dependent Claim
13 words
A process according to claim 3 wherein the semiconductor material is amorphous silicon.
Claim 6
Dependent Claim
29 words
A process according to any one of the preceding claims wherein the current across the device produced by irradiation is measured to determine the conductance state of the device.
Claim 7
Dependent Claim
29 words
A process according to any one of claims 1 to 4 wherein the voltage produced by irradiating the device is measured to determine the conductance state of the device.
Claim 8
Dependent Claim
30 words
A process according to any one of claims 1 to 4 where the electrical power produced by irradiating the device is measured to determine the conductance state of the device.
References Cited (Backward Citations)
No citation records indexed.
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