The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 27, 2013
Filed:
Mar. 19, 2012
LI Xiao, San Jose, CA (US);
Chandu Gorla, Sunnyvale, CA (US);
Abhijit Bandyopadhyay, San Jose, CA (US);
Andrei Mihnea, San Jose, CA (US);
Li Xiao, San Jose, CA (US);
Chandu Gorla, Sunnyvale, CA (US);
Abhijit Bandyopadhyay, San Jose, CA (US);
Andrei Mihnea, San Jose, CA (US);
SanDisk 3D LLC, Milpitas, CA (US);
Abstract
A memory cell in a 3-D read and write memory device has two bipolar resistance-switching layers with different respective switching currents. A low current resistance-switching layer can be switched in set and reset processes while a high current resistance-switching layer remains in a reset state and acts as a protection resistor to prevent excessively high currents on the low current resistance-switching layer. The low and high current resistance-switching layers can be of the same material such as a metal oxide, where the layers differ in terms of thickness, doping, leakiness, metal richness or other variables. Or, the low and high current resistance-switching layers can be of different materials, having one or more layers each. The high current resistance-switching layer can have a switching current which is greater than a switching current of the low current resistance-switching layer by a factor of at least 1.5 or 2.0, for instance.