Programming analog memory elements in a neomorphic computing system

Patent metadata

Field	Value
Publication number	US-12366881-B1
Application number	US-202117408806-A
Country	US
Kind code	B1
Filing date	Aug 23, 2021
Priority date	Aug 23, 2021
Publication date	Jul 22, 2025
Grant date	Jul 22, 2025

Abstract

A method is disclosed herein which includes obtaining an array of analog memory elements. It also includes programming an analog memory element included in the array, where prior to being programmed the analog memory element has a first value for an electrical property, and where it is programmed to cause the analog memory element to perform a computation included in a series of computations performed by the array. Programming the analog memory element includes applying light or heat to the analog memory element, where a value of the electrical property is changed from the first value to a second value based upon application of light or heat to the analog memory element, and further where upon the value of the electrical property being changed from the first value to the second value, the analog memory element is configured to perform the computation responsive to receipt of an input.

First claim

What is claimed is:

1. A method comprising:
obtaining an array of analog memory elements;
programming an analog memory element that is included in the array of analog memory elements, wherein prior to being programmed the analog memory element has a first value for an electrical property, and further wherein the analog memory element is programmed to cause the analog memory element to perform a computation that is included in a series of computations performed by the array of analog memory elements, wherein programming the analog memory element comprises:
applying at least one of light or heat to the analog memory element, wherein the at least one of the light or the heat is directed at the analog memory element by a laser during programming of the analog memory element, wherein at least one light is applied, and further wherein the light has a wavelength of between 500 nm and 600 nm, wherein a value of the electrical property is changed from the first value to a second value based upon application of the at least one of the light or the heat to the analog memory element, and further wherein upon the value of the electrical property being changed from the first value to the second value, the analog memory element is configured to perform the computation responsive to receipt of an input.

2. The method of claim 1 , wherein the electrical property is resistance.

3. The method of claim 1 , wherein both light and heat are applied to the analog memory element.

4. The method of claim 1 , wherein applying at least one of light or heat to the analog memory element comprises applying green laser light to the analog memory element.

5. The method of claim 1 , wherein the analog memory element is formed of a transition metal oxide.

6. The method of claim 1 , wherein the analog memory element is formed of silicon oxide.

7. The method of claim 1 , wherein programming the analog memory element further comprises:
placing the analog memory element in a reducing environment that comprises ions of an element, wherein applying the at least one of light or heat to the analog memory element causes the ions to be inserted into the analog memory element.

8. The method of claim 1 , wherein programming the analog memory element further comprises:
placing the analog memory element in a reducing environment, wherein applying the at least one of light or heat to the analog memory element causes oxygen vacancies to be removed from the analog memory element.

9. The method of claim 1 , wherein the analog memory element is formed of TiO 2 anatase.

10. The method of claim 1 , wherein the computation is a portion of a matrix-vector multiplication.

11. A system that is configured to program an array of analog memory elements such that the array of analog memory elements, when programmed, is configured to perform a computation, the system comprising:
the array of analog memory elements, wherein the array of analog memory elements includes an analog memory element, wherein the analog memory element has a first value for an electrical property of the analog memory element;
an energy source that is configured to emit at least one of heat or light towards the analog memory element, wherein upon the heat or light emitted by the energy source impacting the analog memory element a value of the electrical property of the analog memory element is changed from the first value to a second value, further wherein once the value of the electrical property of the analog memory element is changed from the first value to the second value the analog memory element is configured to perform a portion of the computation upon receipt of input, and further wherein the energy source is a laser configured to direct the at least one of the heat or the light at the analog memory element during programming of the analog memory element, and further wherein the energy source is configured to emit light having a wavelength between 500 nm and 600 nm towards the analog memory element in order to program the analog memory element.

12. The system of claim 11 , wherein the energy source is configured to sequentially direct the at least one of heat or light to several analog memory elements in the array of analog memory elements in order to program the analog memory elements.

13. The system of claim 11 , wherein the electrical property is resistance.

14. The system of claim 11 , wherein each analog memory element in the array of analog memory elements is composed of a transition metal oxide.

15. The system of claim 11 , wherein each analog memory element in the array of analog memory elements is composed of silicon oxide.

16. The system of claim 11 , wherein the energy source is configured to direct both light and heat towards the analog memory element.

17. The system of claim 11 , wherein the computation is a matrix-vector multiplication.

18. An array of programmable analog memory elements, wherein the array comprises:
a first analog memory element that has been programmed to perform a first portion of a computation, wherein the first analog memory element has a first resistance that has been set based upon the first analog memory element being subjected to first light incident having a wavelength of between 500 nm and 600 nm thereon in a reducing environment; and
a second analog memory element that has been programmed to perform a second portion of the computation, wherein the second analog memory element has a second resistance that has been set based upon the second analog memory element being subjected to second light incident thereon in the reducing environment.

Assignees

• Nat Tech & Eng Solutions Sandia Llc

Inventors

• Talin Albert Alec
• Fuller Elliot James

Classifications

• H10D84/942

  Resistors and capacitors · CPC title

• G06N3/065

  Analogue means · CPC title

• G11C13/0069

  Writing or programming circuits or methods · CPC title

• G11C11/54

  using elements simulating biological cells, e.g. neuron · CPC title

• H10B63/22

  of the metal-insulator-metal type · CPC title