Cypress Semiconductor Corporation

Longitude Flash Memory Solutions Ltd.

Mattson Technology, Inc

University of California

Cypress Semiconductor Corportion

Sagy Charel Levy

Krishnaswamy Ramkumar

Igor Polishchuk

Fredrick B Jenne

Sam G Geha

Jeong Soo Byun

Frederick B Jenne

Helmut Puchner

Robin S Bloom

Igor G Kouznetsov

Ravindra Manohar Kapre

Yao Zhi Hu

Peter H Voss

William W C Koutny, Jr

Mehran G Sedigh

Avishai Kepten

Michael Sendler

Sing-Pin Tay

Jeremy L Warren

Jane P Chang

Avashai Kepten

Krishnaswarny Ramkumar

Jeffrey Gelpey

You-Sheng Lin

An embodiment of a nonvolatile charge trap memory device is described. In one embodiment, the device comprises a channel comprising silicon overlying a surface on a substrate electrically connecting a first diffusion region and a second diffusion region of the memory device, and a gate stack intersecting and overlying at least a portion of the channel, the gate stack comprising a tunnel oxide abutting the channel, a split charge-trapping region abutting the tunnel oxide, and a multi-layer blocking dielectric abutting the split charge-trapping region. The split charge-trapping region includes a first charge-trapping layer comprising a nitride closer to the tunnel oxide, and a second charge-trapping layer comprising a nitride overlying the first charge-trapping layer. The multi-layer blocking dielectric comprises at least a high-K dielectric layer.

Nonvolatile charge trap memory device having a high dielectric constant blocking region

A semiconductor device including an oxide-nitride-oxide (ONO) structure having a multi-layer charge storing layer and methods of forming the same are provided. Generally, the method involves: (i) forming a first oxide layer of the ONO structure; (ii) forming a multi-layer charge storing layer comprising nitride on a surface of the first oxide layer; and (iii) forming a second oxide layer of the ONO structure on a surface of the multi-layer charge storing layer. Preferably, the charge storing layer comprises at least two silicon oxynitride layers having differing stoichiometric compositions of Oxygen, Nitrogen and/or Silicon. More preferably, the ONO structure is part of a silicon-oxide-nitride-oxide-silicon (SONOS) structure and the semiconductor device is a SONOS memory transistor. Other embodiments are also disclosed.

Oxide-nitride-oxide stack having multiple oxynitride layers

An example memory device includes a channel positioned between and electrically connecting a first diffusion region and a second diffusion region, and a tunnel dielectric layer, a multi-layer charge trapping layer, and a blocking dielectric layer disposed between the gate structure and the channel. The multi-layer charge trapping layer includes a first dielectric layer disposed abutting a second dielectric layer and an anti-tunneling layer disposed between the first and second dielectric layers. The anti-tunneling layer includes an oxide layer. The first dielectric layer includes oxygen-rich nitride and the second dielectric layer includes oxygen-lean nitride.

Memory transistor with multiple charge storing layers and a high work function gate electrode

An embodiment of a semiconductor memory device including a multi-layer charge storing layer and methods of forming the same are described. Generally, the device includes a channel formed from a semiconducting material overlying a surface on a substrate connecting a source and a drain of the memory device; a tunnel oxide layer overlying the channel; and a multi-layer charge storing layer including an oxygen-rich, first oxynitride layer on the tunnel oxide layer in which a stoichiometric composition of the first oxynitride layer results in it being substantially trap free, and an oxygen-lean, second oxynitride layer on the first oxynitride layer in which a stoichiometric composition of the second oxynitride layer results in it being trap dense. In one embodiment, the device comprises a non-planar transistor including a gate having multiple surfaces abutting the channel, and the gate comprises the tunnel oxide layer and the multi-layer charge storing layer.

Semiconductor devices including non-volatile memory transistors and methods of fabricating the same to improve performance thereof are provided. In one embodiment, the memory transistor comprises an oxide-nitride-oxide (ONO) stack on a surface of a semiconductor substrate, and a high work function gate electrode formed over a surface of the ONO stack. Preferably, the gate electrode comprises a doped polysilicon layer, and the ONO stack comprises multi-layer charge storing layer including at least a substantially trap free bottom oxynitride layer and a charge trapping top oxynitride layer. More preferably, the device also includes a metal oxide semiconductor (MOS) logic transistor formed on the same substrate, the logic transistor including a gate oxide and a high work function gate electrode. In certain embodiments, the dopant is a P+ dopant and the memory transistor comprises N-type (NMOS) silicon-oxide-nitride-oxide-silicon (SONOS) transistor while the logic transistor a P-type (PMOS) transistor. Other embodiments are also disclosed.

Flash memory device and method

A semiconductor device including an oxide-nitride-oxide (ONO) structure having a multi-layer charge storing layer and methods of forming the same are provided. Generally, the method involves: (i) forming a first oxide layer of the ONO structure; (ii) forming a multi-layer charge storing layer comprising nitride on a surface of the first oxide layer; and (iii) forming a second oxide layer of the ONO structure on a surface of the multi-layer charge storing layer. Preferably, the charge storing layer comprises at least two silicon oxynitride layers having differing stochiometric compositions of Oxygen, Nitrogen and/or Silicon. More preferably, the ONO structure is part of a silicon-oxide-nitride-oxide-silicon (SONOS) structure and the semiconductor device is a SONOS memory transistor. Other embodiments are also disclosed.

A method of scaling a nonvolatile trapped-charge memory device and the device made thereby is provided. In an embodiment, the method includes forming a channel region including polysilicon electrically connecting a source region and a drain region in a substrate. A tunneling layer is formed on the substrate over the channel region by oxidizing the substrate to form an oxide film and nitridizing the oxide film. A multi-layer charge trapping layer including an oxygen-rich first layer and an oxygen-lean second layer is formed on the tunneling layer, and a blocking layer deposited on the multi-layer charge trapping layer. In one embodiment, the method further includes a dilute wet oxidation to densify a deposited blocking oxide and to oxidize a portion of the oxygen-lean second layer.

SONOS ONO stack scaling

A method for fabricating a nonvolatile charge trap memory device is described. The method includes subjecting a substrate to a first oxidation process to form a tunnel oxide layer overlying a polysilicon channel, and forming over the tunnel oxide layer a multi-layer charge storing layer comprising an oxygen-rich, first layer comprising a nitride, and an oxygen-lean, second layer comprising a nitride on the first layer. The substrate is then subjected to a second oxidation process to consume a portion of the second layer and form a high-temperature-oxide (HTO) layer overlying the multi-layer charge storing layer. The stoichiometric composition of the first layer results in it being substantially trap free, and the stoichiometric composition of the second layer results in it being trap dense. The second oxidation process can comprise a plasma oxidation process or a radical oxidation process using In-Situ Steam Generation.

Radical oxidation process for fabricating a nonvolatile charge trap memory device

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Zichron Yaakov, Israel

Sagy Charel Levy