The metal–nitride–oxide–semiconductor or metal–nitride–oxide–silicon (MNOS) transistor is a type of
MOSFET
The metal–oxide–semiconductor field-effect transistor (MOSFET, MOS-FET, or MOS FET) is a type of field-effect transistor (FET), most commonly fabricated by the controlled oxidation of silicon. It has an insulated gate, the voltage of which d ...
(metal-oxide-semiconductor field-effect transistor) in which the
oxide
An oxide () is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula. "Oxide" itself is the dianion of oxygen, an O2– (molecular) ion. with oxygen in the oxidation state of −2. Most of the E ...
layer is replaced by a double layer of
nitride and oxide. It is an alternative and supplement to the existing standard
MOS technology, wherein the insulation employed is a nitride-oxide layer. It is used in
non-volatile
Non-volatile memory (NVM) or non-volatile storage is a type of computer memory that can retain stored information even after power is removed. In contrast, volatile memory needs constant power in order to retain data.
Non-volatile memory typic ...
computer memory.
History
The original
MOSFET
The metal–oxide–semiconductor field-effect transistor (MOSFET, MOS-FET, or MOS FET) is a type of field-effect transistor (FET), most commonly fabricated by the controlled oxidation of silicon. It has an insulated gate, the voltage of which d ...
(metal-oxide-semiconductor field-effect transistor, or MOS transistor) was invented by Egyptian engineer
Mohamed M. Atalla and Korean engineer
Dawon Kahng at
Bell Labs in 1959, and demonstrated in 1960.
Kahng went on to invent the
floating-gate MOSFET with
Simon Min Sze at Bell Labs, and they proposed its use as a
floating-gate (FG)
memory cell, in 1967. This was the first form of
non-volatile memory based on the injection and storage of charges in a floating-gate MOSFET,
which later became the basis for
EPROM (erasable
PROM),
EEPROM
EEPROM (also called E2PROM) stands for electrically erasable programmable read-only memory and is a type of non-volatile memory used in computers, usually integrated in microcontrollers such as smart cards and remote keyless systems, or as a ...
(electrically erasable PROM) and
flash memory
Flash memory is an electronic non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR and NAND logic gates. Both us ...
technologies.
In late 1967, a
Sperry Sperry may refer to:
Places
In the United States:
*Sperry, Iowa, community in Des Moines County
*Sperry, Missouri
*Sperry, Oklahoma, town in Tulsa County
*Sperry Chalet, historic backcountry chalet, Glacier National Park, Montana
*Sperry Glacier, ...
research team led by H.A. Richard Wegener invented the metal–nitride–oxide–semiconductor (MNOS) transistor, a type of MOSFET in which the
oxide
An oxide () is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula. "Oxide" itself is the dianion of oxygen, an O2– (molecular) ion. with oxygen in the oxidation state of −2. Most of the E ...
layer is replaced by a double layer of
nitride and oxide.
Nitride was used as a trapping layer instead of a floating gate, but its use was limited as it was considered inferior to a floating gate.
(CT) memory was introduced with MNOS devices in the late 1960s. It had a device structure and operating principles similar to floating-gate (FG) memory, but the main difference is that the charges are stored in a conducting material (typically a doped
polysilicon layer) in FG memory, whereas CT memory stored charges in localized traps within a
dielectric layer (typically made of
silicon nitride).
See also
*
Field-effect transistor
*
MISFET
*
MOSFET
The metal–oxide–semiconductor field-effect transistor (MOSFET, MOS-FET, or MOS FET) is a type of field-effect transistor (FET), most commonly fabricated by the controlled oxidation of silicon. It has an insulated gate, the voltage of which d ...
*
SONOS
SONOS, short for "silicon–oxide–nitride–oxide–silicon", more precisely, " polycrystalline silicon"—"silicon dioxide"—"silicon nitride"—"silicon dioxide"—"silicon",
is a cross sectional structure of MOSFET (metal-oxide-semiconduc ...
References
Transistor types
Field-effect transistors
MOSFETs
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