Intermolecular, Inc.

Prashant B Phatak

Tony P Chiang

Pragati Kumar

Michael A Miller

Sandra Guy Malhotra

Imran Hashim

Venkat Ananthan

Yun Yu Wang

Sunil Shanker

Jinhong Tong

Monica Sawkar Mathur

Wen Wu

Chi-I Lang

Tanmay Kumar

Kurt H Weiner

April Dawn Schricker

Sean Barstow

Nitin Kumar

Mark Harold Clark

Ronald John Kuse

Nobumichi Fuchigami

Nobi Fuchigami

Wayne R French

Hanhong Chen

Igor C Ivanov

Alexander A Gorer

Edward L Haywood

Gaurav Verma

Kevin Kashefi

Ashish Bodke

Dipankar Pramanik

Xiying Costa

Guarav Verma

Xiyang Chen

Wim Deweerd

Xiying Chen

Chi-l Lang

Methods for producing RRAM resistive switching elements having reduced forming voltage include preventing formation of interfacial layers, and creating electronic defects in a dielectric film. Suppressing interfacial layers in an electrode reduces forming voltage. Electronic defects in a dielectric film foster formation of conductive pathways.

Method for reducing forming voltage in resistive random access memory

Control elements that can be suitable for nonvolatile memory device applications are disclosed. The control element can have low leakage currents at low voltages to reduce sneak current paths for non selected devices, and high leakage currents at high voltages to minimize voltage drops during device switching. The control element can be based on a single dielectric layer or on a multilayer dielectric stack.

TiOx based selector element

Selector devices that can be suitable for memory device applications can have low leakage currents at low voltages to reduce sneak current paths for non selected devices, and high leakage currents at high voltages to minimize voltage drops during device switching. In some embodiments, the selector device can include a first electrode, a tri-layer dielectric layer, and a second electrode. The tri-layer dielectric layer can include a high leakage dielectric layer sandwiched between two lower leakage dielectric layers. The low leakage layers can function to restrict the current flow across the selector device at low voltages. The high leakage dielectric layer can function to enhance the current flow across the selector device at high voltages.

Current selector for non-volatile memory in a cross bar array based on defect and band engineering metal-dielectric-metal stacks

Selector elements that can be suitable for nonvolatile memory device applications are disclosed. The selector element can have low leakage currents at low voltages to reduce sneak current paths for non-selected devices, and higher leakage currents at higher voltages to minimize voltage drops during device switching. The selector element can be based on multilayer film stacks (e.g. metal-semiconductor-metal (MSM) stacks). A structure including diamond-like carbon (DLC) can be used to surround the semiconductor layer of the MSM stack. The high thermal conductivity of the DLC structure may serve to remove heat from the selector device while higher currents are flowing through the selector element. This may lead to improved reliability and improved endurance.

Diamond like carbon (DLC) as a thermal sink in a selector stack for non-volatile memory application

This disclosure provides a nonvolatile memory device and related methods of manufacture and operation. The device may include one or more resistive random access memory (ReRAM) approaches to provide a memory device with more predictable operation. In particular, the forming voltage required by particular designs may be reduced through the use of a barrier layer, a reverse polarity forming voltage pulse, a forming voltage pulse where electrons are injected from a lower work function electrode, or an anneal in a reducing environment. One or more of these techniques may be applied, depending on the desired application and results.

Reduction of forming voltage in semiconductor devices

MIMCAP diodes are provided that can be suitable for memory device applications, such as current selector devices for cross point memory array. The MIMCAP diodes can have lower thermal budget as compared to Schottky diodes and controllable lower barrier height and lower series resistance as compared to MIMCAP tunneling diodes. The MIMCAP diode can include a barrier height modification layer, a low leakage dielectric layer and a high leakage dielectric layer. The layers can be sandwiched between two electrodes.

Selector device using low leakage dielectric MIMCAP diode

Selector elements that can be suitable for nonvolatile memory device applications are disclosed. The selector element can have low leakage currents at low voltages to reduce sneak current paths for non-selected devices, and higher leakage currents at higher voltages to minimize voltage drops during device switching. The selector element can be based on multilayer film stacks (e.g. metal-semiconductor-metal (MSM) stacks). The semiconductor layer of the selector element can include a photo-luminescent or electro-luminescent material. Conductive materials of the MSM may include tungsten, titanium nitride, carbon, or combinations thereof.

Photo-induced MSM stack

In some embodiments, a metal oxide second electrode material is formed as part of a MIM DRAM capacitor stack. The second electrode material is doped with one or more dopants. The dopants may influence the crystallinity, resistivity, and/or work function of the second electrode material. The dopants may be uniformly distributed throughout the second electrode material or may be distributed with a gradient in their concentration profile.

Doped electrode for DRAM capacitor stack

Non-volatile resistive-switching memories are described, including a memory element having a first electrode, a second electrode, a metal oxide between the first electrode and the second electrode. The metal oxide switches using bulk-mediated switching, has a bandgap greater than 4 electron volts (eV), has a set voltage for a set operation of at least one volt per one hundred angstroms of a thickness of the metal oxide, and has a leakage current density less than 40 amps per square centimeter (A/cm) measured at 0.5 volts (V) per twenty angstroms of the thickness of the metal oxide.

Non-volatile resistive-switching memories

ALD processing techniques for forming non-volatile resistive-switching memories are described. In one embodiment, a method includes forming a first electrode on a substrate, maintaining a pedestal temperature for an atomic layer deposition (ALD) process of less than 100&#xb0; Celsius, forming at least one metal oxide layer over the first electrode, wherein the forming the at least one metal oxide layer is performed using the ALD process using a purge duration of less than 20 seconds, and forming a second electrode over the at least one metal oxide layer.

ALD processing techniques for forming non-volatile resistive switching memories

Selector elements that can be suitable for nonvolatile memory device applications are disclosed. The selector element can have low leakage currents at low voltages to reduce sneak current paths for non-selected devices, and higher leakage currents at higher voltages to minimize voltage drops during device switching. The selector element can include insulator layers between the semiconductor layer and the metal layers to lower the leakage current of the device. The metal layers of the selector element can include conductive materials such as tungsten, titanium nitride, or combinations thereof.

Tunneling barrier creation in MSM stack as a selector device for non-volatile memory application

MIMCAP devices are provided that can be suitable for memory device applications, such as current selector devices for cross point memory array. The MIMCAP devices can have lower thermal budget as compared to Schottky diodes and controllable lower barrier height and lower series resistance as compared to MIMCAP tunneling diodes. The MIMCAP diode can include a low defect dielectric layer, a high defect dielectric layer, sandwiched between two electrodes having different work function values.

Method of forming an asymmetric MIMCAP or a Schottky device as a selector element for a cross-bar memory array

This disclosure provides a method of fabricating a semiconductor device layer and associated memory cell structures. By performing a surface treatment process (such as ion bombardment) of a semiconductor device layer to create defects having a deliberate depth profile, one may create multistable memory cells having more consistent electrical parameters. For example, in a resistive-switching memory cell, one may obtain a tighter distribution of set and reset voltages and lower forming voltage, leading to improved device yield and reliability. In at least one embodiment, the depth profile is selected to modulate the type of defects and their influence on electrical properties of a bombarded metal oxide layer and to enhance uniform defect distribution.

Surface treatment to improve resistive-switching characteristics

A resistive-switching memory element is described. The memory element includes a first electrode, a porous layer over the first electrode including a point defect embedded in a plurality of pores of the porous layer, and a second electrode over the porous layer, wherein the nonvolatile memory element is configured to switch between a high resistive state and a low resistive state.

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San Jose, CA, United States of America

Prashant B Phatak