# US 2014/0153316 A1 · Methods of Reading and Using Memory Cells

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2014/0153316 A1
- Document ID: US20140153316A1
- Status: Published application
- Kind: A1
- Application number: 14/175,030
- Filed: 2014-02-07
- Published: 2014-06-05
- Earliest claimed: 2009-09-22
- Assignees: Micron Technology, Inc.
- Applicants: Micron Technology, Inc.
- Inventors: Bhaskar Srinivasan; Gurtej S. Sandhu
- Web page: https://patentgrep.com/patent/US20140153316A1

## CPC

- G11C 13/004: {Reading or sensing circuits or methods}
- G11C 13/0002: {using resistive RAM [RRAM] elements}
- G11C 13/0007: {comprising metal oxide memory material, e.g. perovskites}
- G11C 13/0061: {Timing circuits or methods}
- G11C 2013/0052: {Read process characterized by the shape, e.g. form, length, amplitude of the read pulse}
- G11C 2213/72: Array wherein the access device being a diode
- G11C: STATIC STORES (semiconductor memory devices H10B)

## Abstract

Some embodiments include methods of reading memory cells. The memory cells have a write operation that occurs only if a voltage of sufficient absolute value is applied for a sufficient duration of time; and the reading is conducted with a pulse that is of too short of a time duration to be sufficient for the write operation. In some embodiments, the pulse utilized for the reading may have an absolute value of voltage that is greater than or equal to the voltage utilized for the write operation. In some embodiments, the memory cells may comprise non-ohmic devices; such as memristors and diodes.

## Claims

### Claim 1

A method of reading a memory cell, comprising:
providing a memory cell having a frequency dependent write operation, the memory cell comprising a memristor comprising titanium oxide; and
reading the memory cell with a single pulse having a frequency that is at least an order of magnitude faster than a maximum frequency of the write operation.

### Claim 2 (depends on 1)

The method of claim 1 wherein the memory cell comprises a non-ohmic device.

### Claim 3 (depends on 1)

The method of claim 1 wherein the memory cell comprises a non-ohmic device in electrical series with the memristor.

### Claim 4

A method of reading a memory cell, comprising:
providing a memory cell having a frequency dependent write operation, the memory cell comprising a memristor comprising one or both of hafnium oxide and zirconium oxide; and
reading the memory cell with a single pulse having a frequency that is at least an order of magnitude faster than a maximum frequency of the write operation.

### Claim 5 (depends on 4)

The method of claim 4 wherein the reading is conducted while utilizing a voltage with an absolute value that is greater than an absolute value of a voltage utilized in the write operation.

### Claim 6 (depends on 4)

The method of claim 4 wherein the reading is conducted while utilizing a voltage with an absolute value that is less than or equal to an absolute value of a voltage utilized in the write operation.

### Claim 7

A method of reading a memory cell, comprising:
providing an integrated circuit which includes a memory cell having a write operation that occurs at a write voltage and that comprises a lag between a time that the write voltage is applied and a time that the write operation is completed, the memory cell comprising a memristor comprising one or more of titanium oxide, hafnium oxide and zirconium oxide; and
reading the memory cell with a single pulse that is at least an order of magnitude faster than said lag.

### Claim 8 (depends on 7)

The method of claim 7 wherein the memory cell comprises a non-ohmic device.

### Claim 9 (depends on 7)

The method of claim 7 wherein the memory cell comprises a non-ohmic device in electrical series with the memristor.

### Claim 10

A method of using a memory cell, comprising:
writing to an integrated circuit memory cell with a first pulse to change the memory cell from one memory state to another, the first pulse being provided for a first duration of time, the memory cell comprising a memristor comprising one or more of titanium oxide, hafnium oxide and zirconium oxide; and
reading the memory cell to ascertain which of the memory states the memory cell is in; the reading being conducted with a second pulse having a second duration of time that is at least an order of magnitude less than the first duration of time.

### Claim 11 (depends on 10)

The method of claim 10 wherein:
the first pulse is conducted with a first voltage having a first absolute value; the second pulse is conducted with a second voltage having a second absolute value; and
the second absolute value is less than or equal to the first absolute value.

### Claim 12 (depends on 10)

The method of claim 10 wherein:
the first pulse is conducted with a first voltage having a first absolute value; the second pulse is conducted with a second voltage having a second absolute value; and
the second absolute value is greater than the first absolute value.

### Claim 13 (depends on 10)

The method of claim 10 wherein the memory cell comprises a non-ohmic device.

### Claim 14 (depends on 10)

The method of claim 10 wherein the memory cell comprises a non-ohmic device in electrical series with the memristor.