| Crossbar, Inc. Patent applications |
| Patent application number | Title | Published |
| 20120112155 | INTERCONNECTS FOR STACKED NON-VOLATILE MEMORY DEVICE AND METHOD - A method of forming a vertical interconnect for a memory device. The method includes providing a substrate having a surface region and defining a cell region, a first peripheral region, and a second peripheral region. A first thickness of dielectric material is formed overlying the surface region. A first bottom wiring structure spatially configured to extend in a first direction is formed overlying the first dielectric material for a first array of devices. A second thickness of a dielectric material is formed overlying the first wiring structure. The method includes forming an opening region in the first peripheral region. The opening region is configured to extend in a portion of at least the first thickness of dielectric material and the second thickness of dielectric material to expose a portion of the first wiring structure and to expose a portion of the substrate. A second bottom wiring material is formed overlying the second thickness of dielectric material and filling the opening region to form a vertical interconnect structure in the first peripheral region. A second bottom wiring structure is formed from the second wiring material for a second array of devices. The second bottom wiring structure is separated from the first bottom wiring structure by at least the second thickness of dielectric material and spatially configured to extend in the first direction. The first wiring structure and the second wiring structure are electrically connected by the vertical interconnect structure in the first peripheral region to a control circuitry on the substrate. | 05-10-2012 |
| 20120108030 | METHOD FOR OBTAINING SMOOTH, CONTINUOUS SILVER FILM - A method for forming a semiconductor device including a resistive memory cell includes providing a substrate having an upper surface. A first conductive layer is formed over the upper surface of the substrate. An amorphous silicon layer is formed over the first conductive layer. A surface of the amorphous silicon layer is cleaned to remove native oxide formed on the surface of the amorphous silicon layer. A silver layer is deposited over the amorphous silicon layer after removing the native oxide by performing the cleaning step. The resistive memory cell includes the first conductive layer, the amorphous silicon layer, and the second conductive layer. The surface of the amorphous silicon layer is cleaned to prevent silver agglomeration on the native oxide. | 05-03-2012 |
| 20120087169 | CIRCUIT FOR CONCURRENT READ OPERATION AND METHOD THEREFOR - A non-volatile memory device includes a plurality of memory units provided in an array, each memory unit having a plurality of resistive memory cells and a local word line. Each resistive memory units has a first end and a second end, the second ends of the resistive memory cells of each memory unit being coupled to the local word line of the corresponding memory unit. A plurality of bit lines is provided, each bit line being coupled to the first end of one of the resistive memory cells. A plurality of select transistors is provided, each select transistor being assigned to one of the memory units and having a drain terminal coupled to the local word line of the assigned memory unit. First and second global word lines are provided, each global word line being coupled to a control terminal of at least one select transistor. First and second source lines are provided, each source line being coupled to a source terminal of at least one select transistor. The memory device is configured to concurrently read out all of the resistive memory cells in one of the memory units selected for a read operation. | 04-12-2012 |
| 20120075907 | RESISTOR STRUCTURE FOR A NON-VOLATILE MEMORY DEVICE AND METHOD - A non-volatile resistive switching memory device. The device includes a first electrode, a second electrode, a switching material in direct contact with a metal region of the second electrode, and a resistive material disposed between the second electrode and the switching material. The resistive material has an ohmic characteristic and a resistance substantially the same as an on state resistance of the switching device. The resistive material allows for a change in a resistance of the switching material upon application of voltage pulse without time delay and free of a reverse bias after the voltage pulse. The first voltage pulse causes a programming current to flow from the second electrode to the first electrode. The resistive material further causes the programming current to be no greater than a predetermined value. | 03-29-2012 |
| 20120074507 | INTEGRATION OF AN AMORPHOUS SILICON RESISTIVE SWITCHING DEVICE - An integrated circuit device. The integrated circuit device includes a semiconductor substrate having a surface region. A gate dielectric layer overlies the surface region of the substrate. The device includes a MOS device having a p+ active region. The p+ active region forms a first electrode for a resistive switching device. The resistive switching device includes an amorphous silicon switching material overlying the p+ active region and a metal electrode overlies the first metal conductor structure. The metal electrode includes a metal material, upon application of a positive bias to the metal electrode, forms a metal region in the amorphous silicon switching material. The MOS device provides for a select transistor for the integrated circuit device. | 03-29-2012 |
| 20120074374 | CONDUCTIVE PATH IN SWITCHING MATERIAL IN A RESISTIVE RANDOM ACCESS MEMORY DEVICE AND CONTROL - A non-volatile memory device structure. The device structure includes a first electrode, a second electrode, a resistive switching material comprising an amorphous silicon material overlying the first electrode, and a thickness of dielectric material having a thickness ranging from 5 nm to 10 nm disposed between the second electrode and the resistive switching layer. The thickness of dielectric material is configured to electrically breakdown in a region upon application of an electroforming voltage to the second electrode. The electrical breakdown allows for a metal region having a dimension of less than about 10 nm by 10 nm to form in a portion of the resistive switching material. | 03-29-2012 |
| 20120043621 | STACKABLE NON-VOLATILE RESISTIVE SWITCHING MEMORY DEVICE AND METHOD - A method for forming a vertically stacked memory device. The method includes providing a semiconductor substrate having a surface region and forming a first dielectric material overlying the surface region. A first plurality of memory cells are formed overlying the first dielectric material. Each of the first plurality of memory cells includes at least a first top metal wiring structure spatially extending in a first direction, a first bottom wiring structure spatially extending in a second direction orthogonal to the first top metal wiring structure, and a first switching element sandwiched in an intersection region between the first top metal wiring structure and the first bottom metal wiring structure. In a specific embodiment, the method forms a thickness of second dielectric material overlying the first plurality of memory. A second plurality of memory cells are formed overlying the second dielectric material. Each of the second plurality of memory cells includes at least a second top metal wiring structure extending in the first direction, a second bottom wiring structure arranged spatially orthogonal to the second top metal wiring structure, and a second switching element sandwiched in an intersection region of the second top metal wiring structure and the second bottom metal wiring structure. | 02-23-2012 |
| 20120043520 | DISTURB-RESISTANT NON-VOLATILE MEMORY DEVICE AND METHOD - A method of forming a disturb-resistant non volatile memory device. The method includes providing a semiconductor substrate having a surface region and forming a first dielectric material overlying the surface region. A first wiring material overlies the first dielectric material, a doped polysilicon material overlies the first wiring material, and an amorphous silicon switching material overlies the said polysilicon material. The switching material is subjected to a first patterning and etching process to separating a first strip of switching material from a second strip of switching spatially oriented in a first direction. The first strip of switching material, the second strip of switching material, the contact material, and the first wiring material are subjected to a second patterning and etching process to form at least a first switching element from the first strip of switching material and at least a second switching element from the second strip of switching material, and a first wiring structure comprising at least the first wiring material and the contact material. The first wiring structure being is in a second direction at an angle to the first direction. | 02-23-2012 |
| 20120043519 | DEVICE SWITCHING USING LAYERED DEVICE STRUCTURE - A resistive switching device. The device includes a first electrode comprising a first metal material overlying the first dielectric material and a switching material comprising an amorphous silicon material. The device includes a second electrode comprising at least a second metal material. In a specific embodiment, the device includes a buffer material disposed between the first electrode and the switching material. The buffer material provides a blocking region between the switching material and the first electrode so that the blocking region is substantially free from metal particles from the second metal material when a first voltage is applied to the second electrode. | 02-23-2012 |
| 20120015506 | TWO TERMINAL RESISTIVE SWITCHING DEVICE STRUCTURE AND METHOD OF FABRICATING - A method of forming a two terminal device. The method includes forming a first dielectric material overlying a surface region of a substrate. A bottom wiring material is formed overlying the first dielectric material and a switching material is deposited overlying the bottom wiring material. The bottom wiring material and the switching material is subjected to a first patterning and etching process to form a first structure having a top surface region and a side region. The first structure includes at least a bottom wiring structure and a switching element having a first side region, and a top surface region including an exposed region of the switching element. A second dielectric material is formed overlying at least the first structure including the exposed region of the switching element. The method forms an opening region in a portion of the second dielectric layer to expose a portion of the top surface region of the switching element. A top wiring material including a conductive material is formed overlying at lease the opening region such that the conductive material is in direct contact with the switching element. A second etching process is performed to form at least a top wiring structure. In a specific embodiment, the side region of the first structure including a first side region of the switching element is free from a contaminant conductive material from the second etching process. | 01-19-2012 |
| 20120012806 | IMPROVED ON/OFF RATIO FOR NON-VOLATILE MEMORY DEVICE AND METHOD - This application describes a method of forming a switching device. The method includes forming a first dielectric material overlying a surface region of a substrate. A bottom wiring material is formed overlying the first dielectric material and a switching material is deposited overlying the bottom wiring material. The bottom wiring material and the switching material is subjected to a first patterning and etching process to form a first structure having a top surface region and a side region. The first structure includes at least a bottom wiring structure and a switching element having a top surface region including an exposed region of the switching element. A second dielectric material is formed overlying at least the first structure including the exposed region of the switching element. The method forms a first opening region in a portion of the second dielectric layer to expose a portion of the top surface region of the switching element. A dielectric side wall structure is formed overlying a side region of the first opening region. A top wiring material including a conductive material is formed overlying at lease the top surface region of the switching element such that the conductive material is in direct contact with the switching element. The side wall spacer reduces a contact area for the switching element and the conductive material and thus a reduced active device area for the switching device. In a specific embodiment, the reduced area provides for an increase in device ON/OFF current ratio. | 01-19-2012 |
| 20120008366 | RESTIVE MEMORY USING SiGe MATERIAL - A resistive memory device includes a first electrode; a second electrode having a polycrystalline semiconductor layer that includes silicon; a non-crystalline silicon structure provided between the first electrode and the second electrode. The first electrode, second electrode and non-crystalline silicon structure define a two-terminal resistive memory cell. | 01-12-2012 |
| 20120007035 | Intrinsic Programming Current Control for a RRAM - A resistive switching device. The device includes a substrate and a first dielectric material overlying a surface region of the substrate. The device includes a first electrode overlying the first dielectric material and an optional buffer layer overlying the first electrode. The device includes a second electrode structure. The second electrode includes at least a silver material. In a specific embodiment, a switching material overlies the optional buffer layer and disposed between the first electrode and the second electrode. The switching material comprises an amorphous silicon material in a specific embodiment. The amorphous silicon material is characterized by a plurality of defect sites and a defect density. The defect density is configured to intrinsically control programming current for the device. | 01-12-2012 |
| 20110312151 | PILLAR STRUCTURE FOR MEMORY DEVICE AND METHOD - A method of forming a memory device. The method provides a semiconductor substrate having a surface region. A first dielectric layer is formed overlying the surface region of the semiconductor substrate. A bottom wiring structure is formed overlying the first dielectric layer and a second dielectric material is formed overlying the top wiring structure. A bottom metal barrier material is formed to provide a metal-to-metal contact with the bottom wiring structure. The method forms a pillar structure by patterning and etching a material stack including the bottom metal barrier material, a contact material, a switching material, a conductive material, and a top barrier material. The pillar structure maintains a metal-to-metal contact with the bottom wiring structure regardless of the alignment of the pillar structure with the bottom wiring structure during etching. A top wiring structure is formed overlying the pillar structure at an angle to the bottom wiring structure. | 12-22-2011 |
| 20110305066 | WRITE AND ERASE SCHEME FOR RESISTIVE MEMORY DEVICE - A method for programming a two terminal resistive memory device, the method includes applying a bias voltage to a first electrode of a resistive memory cell of the device; measuring a current flowing through the cell; and stopping the applying of the bias voltage if the measured current is equal to or greater than a predetermined value. | 12-15-2011 |
| 20110305065 | NON-VOLATILE VARIABLE CAPACITIVE DEVICE INCLUDING RESISTIVE MEMORY CELL - A non-volatile variable capacitive device includes a capacitor defined over a substrate, the capacitor having an upper electrode and a resistive memory cell having a first electrode, a second electrode, and a switching layer provided between the first and second electrodes. The resistive memory cell is configured to be placed in a plurality of resistive states according to an electrical signal received. The upper electrode of the capacitive device is coupled to the second electrode of the resistive memory cell. The resistive memory cell is a two-terminal device. | 12-15-2011 |
| 20110305064 | INTERFACE CONTROL FOR IMPROVED SWITCHING IN RRAM - A memory device has a crossbar array including a first array of first electrodes extending along a first direction. A second array of second electrodes extends along a second direction. A non-crystalline silicon structure provided between the first electrode and the second electrode at an intersection defined by the first array and the second array. The non-crystalline silicon structure has a first layer having a first defect density and a second layer having a second defect density different from the first defect density. Each intersection of the first array and the second array defines a two-terminal memory cell. | 12-15-2011 |