Intermolecular, Inc.

Fairchild Semiconductor Corporation

Venkat Ananthan

Prashant B Phatak

Imran Hashim

Salman Akram

Tony P Chiang

Mark Harold Clark

Monica Sawkar Mathur

Wayne R French

In a general aspect, a power semiconductor device can include a silicon carbide (SiC) substrate and a SiC epitaxial layer disposed on the SiC substrate. The device can include a well region disposed in the epitaxial layer, a source region disposed in the well region and a gate trench disposed in the epitaxial layer and adjacent to the source region. The gate trench can have a depth that is greater than a depth of the well region and less than a depth of the epitaxial layer. The device can include a hybrid gate dielectric disposed on a sidewall of the gate trench and a bottom surface of the gate trench. The hybrid gate dielectric can include a first high-k material and a second high-k dielectric material that is different than the first high-k dielectric material. The device can include a conductive gate electrode disposed on the hybrid gate dielectric.

Hybrid gate dielectrics for semiconductor power devices

In a general aspect, a power semiconductor device can include a silicon carbide (SiC) substrate and a SiC epi-layer disposed on the SiC substrate. The device can also include a first well region, a second well region disposed in the SiC epi-layer, a first source region disposed in the first well region, and a second source region disposed in the second well region. The device can further include a gate structure disposed on the SiC epi-layer and extending between the first source region and the second source region. The gate structure can include a hybrid gate dielectric. The hybrid gate dielectric can include a first high-k dielectric material and a second high-k dielectric material. The device can also include a conductive gate electrode disposed on the hybrid gate dielectric.

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

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

A combination of deposition processes can be used to evaluate layer properties using a combinatorial workflow. The processes can include a base ALD process and another process, such as a PVD process. The high productivity combinatorial technique can provide an evaluation of the material properties for given ALD base layer and PVD additional elements. An ALD process can then be developed to provide the desired layers, replacing the ALD and PVD combination.

Dielectric doping using high productivity combinatorial methods

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. 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 low band gap dielectric layer disposed between two higher band gap dielectric layers. The high band gap dielectric layers can be doped with doping materials to form traps at energy levels higher than the operating voltage of the memory device.

Using multi-layer MIMCAPs with defective barrier layers as selector element for a cross bar memory array

The embodiments describe methods and apparatuses for combinatorial optimization of interlayer parameters for capacitor stacks. The capacitor stacks may include a substrate, an insulating layer disposed on the substrate, a ruthenium disposed electrode on the insulating layer, and an interlayer disposed on the ruthenium electrode, where the interlayer is configured to prevent etching of the electrode when growing a high-k dielectric using an ozone-based precursor. The parameters for forming the interlayer may include interlayer thickness, precursor chemistry, oxidant strength, precursor purge times, oxidant purge times, and other suitable parameters. Each of these parameters may be evaluated through deposition of the capacitor stacks through a combinatorial optimization process. Thus, a plurality of different parameters may be evaluated with a single substrate to ascertain associated properties of Ruthenium electrode etching in a combinatorial manner.

Combinatorial optimization of interlayer parameters

Resistive random access memory (ReRAM) cells can include a ZnTe switching layer and TiN or Pt electrodes. The combination of the switching layer of ZnTe and the electrodes of TiN or Pt is designed to achieve desirable performance characteristics, such as low current leakage as well as low and consistent switching currents. High temperature anneal of the ZnTe switching layer can further improve the performance of the ReRAM cells. The switching layer may be deposited using various techniques, such as sputtering or atomic layer deposition (ALD).

ZnTe on TiN or Pt electodes with a portion operable as a current limiting layer for ReRAM applications

Using multi-layer MIMCAPs in the tunneling regime as selector element for a cross-bar memory array

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

Dual shadow mask design can overcome the size and resolution limitations of shadow masks to provide capacitor structures with small effective areas. The capacitor structures have bottom and top electrode layers patterned using shadow masks, sandwiching a dielectric layer. The effective areas of the capacitors are the overlapping areas of the top and bottom electrodes, thus allowing small area sizes without subjected to the size limitation of the electrodes. The dual shadow mask design can be used in conjunction with high productivity combinatorial processes for screening and optimizing dielectric materials and fabrication processes.

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Cupertino, CA, United States of America

Venkat Ananthan